Stomata are tiny pores on the plant leaf surface that regulate the exchange of water and gases between the plant and the external environment.They are crucial for photosynthesis,water use efficiency(WUE),and the plant...Stomata are tiny pores on the plant leaf surface that regulate the exchange of water and gases between the plant and the external environment.They are crucial for photosynthesis,water use efficiency(WUE),and the plant’s ability to adapt to environmental changes.Stomatal movement is vital for understanding how plants adapt to environmental stress and optimize resource utilization.Changes in environmental conditions,especially the quality and intensity of light throughout the day,affect stomatal dynamics and diurnal behavior,which in turn impact photosynthetic efficiency and water-use efficiency.In this review,we summarize the biophysical principles and mechanisms of stomatal movement regulated by ion transport at the plasma membrane,vacuolar membrane and metabolic activity through persulfidation or S-nitrosylation modifications.Specifically,we focus on recent progress in the regulation of stomatal movement by different light qualities,and summarize the photochemical and biochemical events underlying photoreceptors as well as the knowledge of novel regulatory functions and signaling in the multilayer control of stomatal movement and environmental adaptation.Furthermore,as rising global temperatures and increased water needs of farming methods are expected to escalate future crop losses,we explore the potential of smart LED lighting and gene editing technology in enhancing photosynthetic efficiency and water-use efficiency,leading to increased crop biomass and higher crop yields.展开更多
Rapid urbanization has contributed to global increases in air pollution derived from urban areas.Unlike natural forests,urban forests are exposed to higher concentrations of airborne pollutants due to the strong urban...Rapid urbanization has contributed to global increases in air pollution derived from urban areas.Unlike natural forests,urban forests are exposed to higher concentrations of airborne pollutants due to the strong urban-suburban-rural pollutant emission gradients.However,there remains a pressing lack of available information pertaining to the urban air pollutionrelated effects on the leaf economics spectrum,anatomical,ultrastructural,and stomatal traits of tree species along an urban-rural gradient.Here,the degree to which urban air pollution impacts the adaption of greening tree species and associated service functions was assessed by sampling five common tree species(Acer pictum,Fraxinus chinensis,Koelreuteria paniculata,Salix babylonica,Sophora japonica)along urban-rural-natural forests in the Beijing metropolitan region of China.These analyses revealed a significant reduction in leaf mass per unit area(-13.4%),leaf thickness(-16.7%),and stomatal area(-27.5%)with increasing proximity to areas of greater air pollution that coincide with significant increases in leaf tissue density(+12.6%),leaf nitrogen content(+10.1%),relative chlorophyll content(+2.7%),and stomatal density(+11.9%).Higher air pollution levels were associated with organelle changes including gradual disintegration of chloroplasts,larger intercellular spaces and apparent starch and plastoglobuli deposition.Air pollutionwas conducive to the strengthening of the trade-off potential and adaptation strategies of trees in urban ecosystems,which are associated with trees with a rapid investment return strategy associated with thick leaves and strong photosynthetic capacity.These results provide strong empirical evidence of the profound air pollution-induced changes in leaf functional traits and adaption ability of urban forest tree species.展开更多
[Objective]This study was to reveal the physiological and ecological mechanism of growth and development of test-tube seedlings.[Methods]Leaf stomata of test-tube seedlings of D.loddigesii and D.candidum at different ...[Objective]This study was to reveal the physiological and ecological mechanism of growth and development of test-tube seedlings.[Methods]Leaf stomata of test-tube seedlings of D.loddigesii and D.candidum at different growth and development stages were observed under scanning electron microscope,and their fluorescence induction response curve was assayed by using modulate fluorometer.[Results] At each growth and development stage,D.loddigesii test-tube seedling has a higher leaf stomatal density over D.candidum,while a lower stomata opening rate.Along with the growth,the size of stomata of both D.loddigesii and D.candidum did not change obviously,but their stoma density increased by 83% and 17.6% respectively.Leaf stomata opening rate reached the highest at the age of 240-day-old.Under the conditions of three settled light intensities,stomatal opening degree of D.loddigesii was increased by the intensity of illumination,the maximum aperture occurred at the light intensity of 54 μmol/m2·s.Given the same culture condition,both the maximum electron transport rate（14 μmol/m2·s）and light saturation point（318 μmol/m2·s）of D.loddigesii test-tube seedling are lower than that of D.candidum（20 μmol/m2·s,483 μmol/m2·s）.Moreover,the potential photosynthetic capacity of D.loddigesii is relatively poor.[Conclusion]The photosynthetic rate varies among different species of Dendrobium,which could be attributed to their different stomatal characteristics.Usually,the light intensity of tissue culture chamber is set up as 27 μmol/（m2·s）,where both D.loddigesii and D.candidum do not acquire an optimal state for their leaf stomatal opening.Considering the characteristics to select suitable culture condition,the stomatal aperture and photosynthetic rate could be enhanced,which can promote the growth and development of test-tube seedlings.展开更多
Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less ...Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less is known about how young GCs develop into mature functional stomata.Here we perform a maturomics study on stomata,with“maturomics”defined as omics analysis of the maturation process of a tissue or organ.We develop an integrative scheme to analyze three public stomata-related single-cell RNAseq datasets and identify a list of 586 genes that are specifically up-regulated in all three datasets during stomatal maturation and function formation.The list,termed sc_586,is enriched with known regulators of stomatal maturation and functions.To validate the reliability of the dataset,we selected two candidate G2-like transcription factor genes,MYS1 and MYS2,to investigate their roles in stomata.These two genes redundantly regulate the size and hoop rigidity of mature GCs,and the mys1 mys2 double mutants cause mature GCs with severe defects in regulating their stomatal apertures.Taken together,our results provide a valuable list of genes for studying GC maturation and function formation.展开更多
1-Deoxy-D-xylulose-5-phosphate reductoisomerase （DXR） is an important enzyme involved in the 2-C-methyi-D- erythritol-4-phosphate （MEP） pathway which provides the basic five-carbon units for isoprenoid biosynthesi...1-Deoxy-D-xylulose-5-phosphate reductoisomerase （DXR） is an important enzyme involved in the 2-C-methyi-D- erythritol-4-phosphate （MEP） pathway which provides the basic five-carbon units for isoprenoid biosynthesis. To investigate the role of the MEP pathway in plant development and metabolism, we carried out detailed analyses on a dxr mutant （GK_215C01） and two DXR transgenic co-suppression fines, OX-DXR-L2 and OX-DXR-L7. We found that the dxr mutant was albino and dwarf. It never bolted, had significantly reduced number of trichomes and most of the stomata could not close normally in the leaves. The two co-suppression lines produced more yellow inflorescences and albino sepals with no trichomes. The transcription levels of genes involved in tricbome initiation were found to be strongly affected, including GLABRA1, TRANSPARENT TESTA GLABROUS 1, TRIPTYCHON and SPINDLY, expression of which is regulated by gibberellic acids （GAs）. Exogenous application of GA3 could partially rescue the dwarf phenotype and the trichome initiation of dxr, whereas exogenous application of abscisic acid （ABA） could rescue the stomata closure defect, suggesting that lower levels of both GA and ABA contribute to the phenotype in the dxr mutants. We further found that genes involved in the biosynthetic pathways of GA and ABA were coordinately regulated. These results indicate that disruption of the plastidial MEP pathway leads to biosynthetic deficiency of photosynthetic pigments, GAs and ABA, and thus the developmental abnormalities, and that the flux from the cytoplasmic mevalonate pathway is not sufficient to rescue the deficiency caused by the blockage of the plastidial MEP pathway. These results reveal a critical role for the MEP biosynthetic pathway in controlling the biosynthesis of isoprenoids.展开更多
To observe the regulating effects of vascular endothelial growth factor (VEGF) and angiotensinⅡ (ANG II) on the frog’s pericardium, lymphatic stomata and angiogenesis so as to reveal their effects and mechanism on t...To observe the regulating effects of vascular endothelial growth factor (VEGF) and angiotensinⅡ (ANG II) on the frog’s pericardium, lymphatic stomata and angiogenesis so as to reveal their effects and mechanism on the mesothelial permeability, lymphatic stoma regulation and myocardial hypertrophy. Methods. VEGF and ANGⅡ were injected into the frog’s peritoneal cavity so as to examine the changes of the pericardial stromata by using transmission electron microscopy, scanning electron microscopy and computerized imaging analysis. Results. Scattered distributed pericardial stomata were found on the parietal pericardium of the frog with a few sinusoid mesothelial cells, whose blood supply was directly from the cardiac chambers flowing into the trabecular spaces of the myocardium (because there are no blood vessels in the myocardium of the frog). The average diameters of the pericardial stomata in VEGF and ANGⅡ groups were 1.50μ m and 1.79μ m respectively, which were much larger than those in the control group (0.72μ m, P Conclusions. VEGF and ANGⅡ could strongly regulate the pericardial stomata by increasing their numbers and openings with larger diameters and higher distribution density. They could also increase the sinusoid areas with the result of the higher permeability of the pericardium, which clearly indicated that VEGF and ANGⅡ could speed up the material transfer of the pericardial cavity and play an important role in preventing myocardial interstitial edema. Yet there was no strong evidence to show the angiogenesis in the myocardium.展开更多
The development of the science of cytology and genetics, particularly on cell structure and function provided a breakthrough for breeders and allowed for early selection. Character of stomata density on some commoditi...The development of the science of cytology and genetics, particularly on cell structure and function provided a breakthrough for breeders and allowed for early selection. Character of stomata density on some commodities was reported as important factor to determine the disease resistance. The research was done for getting information about the differences in the stomata characters influenced on the level of Vascular Streak dieback （VSD） resistance on cocoa. The research was conducted in the Laboratory of Genetics, Gadjah Mada University and leaves samples were conducted in Kendeng Lembu Gardens, PTPN XII. The research used a split plot design with three factors included the type of clones with different levels of VSD disease resistance （PA 191, BL 703 and GS 29）, leaf position （top, middle and base） and leaf age （young and old）. Stomata characters included number of stomata, stomata opening width, stomata wide and stomata diameter were observed. The results showed that the stomata characters in three cacao genotypes with different resistance levels indicated a difference in number of stomata, stomata size, stomata opening width, stomata wide and stomata diameter. Stomata number, stomata opening width and stomata diameter on PA 191 （resistance clone） were lower than the susceptible clones （BL 703 dan GS 29）. The lowest of number and diameter stomata on the base position on the old leaves tissues. Number of stomata, stomata opening width and stomata diameter were estimated role in mechanism of VSD resistance and that were expected could be used as criteria selection to VSD resistance.展开更多
[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the rela...[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the relation of leaf stomatal density （SD）, length （SL） and width （ SW）, stomatal conductance （g,）, photosynthetic rate （ Pn ）, transpiration rate （ Tr） to grain yield per plant and index of drought resistance （IDR） on the 10th and 20t＂ day after anthesis under the conditions of drought stress and normal irrigation were discussed by the methods of correlation analysis and path analysis. [ Result] Under the two water conditions, the correlations of these stomatal traits with yield components and IDR were mostly not significant on the 10t＂ day after anthesis, but there were significantly positive correlations between thousand kernel weight （TKW） and these traits on the 20^th day after anthesis. Path analysis showed that g,, Pn and Tt, were main factors affecting yield per plant （YPP） and IDR, and they had stron- ger direct effects on YPP and IDR, while their indirect interaction was also strong. The direct effects of SD, SL and SW on YPP and IDR were small, as well as their indirect action among SD, SL and SW. On the other hand, the correlations between SD and SL were significant, and the correlations of SL with SW, gn, P, and Tt, were extremely significant on the 10th and 20th day after anthesis under the two water conditions. However, the correlations of SD and SL with g,, P,, and Tr changed with water conditions or growth stages, showing that water conditions or growth stages had great effects on the correlations between two traits. Therefore, it is not always a good means to improve stomatal conductance, photosynthetic rate and transpiration rate and hence promote wheat yield by selecting stomatal density and size. [ Conclusion] The research could provide scientific references for revealing the roles of leaf stomatal traits in wheat breeding for drought resistance.展开更多
Stomatal closure,which serves to limit water loss,represents one of the most rapid and critical reactions of plants,occurring not only in response to drought but also to a range of other stressors,including salinity,e...Stomatal closure,which serves to limit water loss,represents one of the most rapid and critical reactions of plants,occurring not only in response to drought but also to a range of other stressors,including salinity,extreme temperatures,heavy metals,gaseous toxicants,and pathogen infection.ABA is considered to be the main regulator of stomatal movements in plants under abiotic stress.In the last two decades,however,the list of plant hormones and other physiologically active substances that affect stomatal status has expanded considerably.It is believed that stomata are regulated by a complex multicomponent network of compounds consisting of hormones and signaling mediators.A special place among them is occupied by gasotransmitters,endogenously synthesized gaseous compounds with signaling functions.The most studied of them are nitrogen monoxide(NO),hydrogen sulfide(H2S),and carbon monoxide(CO).Carbon dioxide(CO_(2)),not yet classified as a classical gasotransmitter,is also considered an important gaseous regulatory molecule.Information has been obtained on the ability of each of these gases to induce stomatal responses in plants.Gasotransmitters are also involved as mediators in stomatal responses induced by various plant hormones and other compounds,particularly ABA,jasmonic and salicylic acids,brassinosteroids,and polyamines.This review examines the functional interactions between gasotransmitters at the level of influencing each other’s synthesis and interactions with other mediators,especially ROS and calcium ions,in their involvement in providing stomatal responses.The latest information on proteins involved in stomatal regulation and undergoing post-translational modification under the action of gasotransmitters,including protein kinases,ion channel proteins,aquaporins,pro-and antioxidant enzymes,is also summarized.The possibilities of practical use of gasotransmitter donors as stress protective agents contributing to the normalization of plant water metabolism are considered.展开更多
Preliminary research results indicated that the stomata is one important trait that can be used as an indicator of resistance to vascular streak dieback （VSD） disease. The influence of genotype and environment on th...Preliminary research results indicated that the stomata is one important trait that can be used as an indicator of resistance to vascular streak dieback （VSD） disease. The influence of genotype and environment on the stomatal characters is expected to provide information for specificlocations （habitats） suitable for planting cocoa in particular to avoid VSD attack. The research was conducted at KendengLembu, PTPNXII, East Java. Experimental design used a splitplot design testing： location （altitude） and genotype factors. The location factors, distinguished on the basis of the altitude, were labelled highlands and lowlands. The genotype factors consisted of three clones with different levels of resistance to VSD diseases： PA 191 （tolerant）, BL 703 and GC 29 （susceptible）. The cocoa clones observed were top grafted onto locally available rootstock seedling and planted in 2006-2007. The maintenance of the plants was conducted in accordance with the standards of cocoa cultivation in the PTPN XII. Parameters measured were leaf stomata traits at different positions of the leaf （tip, middle and base）. Characters observed were the number of stomata, opening width of stomata, and diameter of the stomata. The results of the research showed that PA 191 in the lowlands had the lowest number, diameter and opening width of stomata. In contrast, GC 29 in the lowlands showed the highest number of stomata PA 191 and BL 703 in the highlands had a number, diameter and openings width of stomata that was relatively low compared with GC 29. However, the characters of the stomata （number, diameter and openings width of stomata） of the three genotypes in the highland showed a smaller value in each case than in the lowlands. The severity level of VSD attack was greater in the lowlands than in the highlands and PA 191 showed the lowest level of VSD attack at both altitudes.展开更多
The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it...The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it essential to better understand this species for its conservation and valorization.Through our work on 7 provenances of Pistacia atlantica distributed across different bioclimates in Algeria and based on 28 quantitative and qualitative leaf,trichome,and stomatal traits,it was revealed that the Atlas pistachio tree exhibits significant ecotypic variability linked to its habitat and a high adaptability to extreme conditions in its environments(aridity and altitude).Indeed,statistical analyses indicate a substantial heterogeneity in the studied characteristics among different ecotypes of P.atlantica.Genetic factors undoubtedly play a primary role in this variability,but environmental factors also exert a remarkable impact on this heterogeneity.Gender also plays a crucial role in this variability.Microphotographs of leaf samples taken under scanning electron microscopy(SEM),such as the density and type of trichomes,and form and position of stomates in the epidermis,can provide an important taxonomic tool for identifying Pistacia species and valuable insights into their adaptation to xeric conditions,thus enabling their use in desertification control projects and the rehabilitation of highly degraded forest environments such as those found in the“Green Dam”initiative.展开更多
Maize(Zea mays L.)growth and yield are severely limited by drought stress worldwide.Stomata play crucial roles in transpiration and gas exchange and are thus essential for improving plant water-use efficiency(WUE)to h...Maize(Zea mays L.)growth and yield are severely limited by drought stress worldwide.Stomata play crucial roles in transpiration and gas exchange and are thus essential for improving plant water-use efficiency(WUE)to help plants deal with the threat of drought.In this study,we characterized the maize dsd1(decreased stomatal density 1)mutant,which showed defects in stomatal development,including guard mother cell differentiation,subsidiary cell formation and guard cell maturation.DSD1 encodes the basic helix-loop-helix transcription factor INDUCER OF CBF EXPRESSION b(ZmICEb)and is a homolog of ICE1 in Arabidopsis(Arabidopsis thaliana).DSD1/ZmICEb is expressed in stomatal file cells throughout stomatal development and plays a conserved role in stomatal development across maize and Arabidopsis.Mutations in DSD1/ZmICEb dramatically improved drought tolerance and WUE in maize and reduced yield losses under drought conditions.Therefore,DSD1/ZmICEb represents a promising candidate target gene for the genetic improvement of drought tolerance in maize by manipulating stomatal density.展开更多
Members of the cyclic nucleotide-gated channel(CNGC)proteins are reportedly involved in a variety of biotic and abiotic responses and stomatal movement.However,it is unknown if and how a single member could regulate m...Members of the cyclic nucleotide-gated channel(CNGC)proteins are reportedly involved in a variety of biotic and abiotic responses and stomatal movement.However,it is unknown if and how a single member could regulate multiple responses.Here we characterized three closely related CNGC genes in rice,OsCNGC14,OsCNGC15 and OsCNGC16,to determine whether they function in multiple abiotic stresses.The loss-of-function mutants of each of these three genes had reduced calcium ion(Ca^(2+))influx and slower stomatal closure in response to heat,chilling,drought and the stress hormone abscisic acid(ABA).These mutants also had reduced tolerance to heat,chilling and drought compared with the wildtype.Conversely,overexpression of OsCNGC16 led to a more rapid stomatal closure response to stresses and enhanced tolerance to heat,chilling and drought.The tight association of stomatal closure and stress tolerance strongly suggests that tolerance to multiple abiotic stresses conferred by these Os CNGC genes results at least partially from their regulation of stomatal movement.In addition,physical interactions were observed among the three Os CNGC proteins but not with a distantly related CNGC,suggesting the formation of hetero-oligomers among themselves.This study unveils the crucial role of OsCNGC14,15 and 16 proteins in stomatal response and tolerance to multiple stresses,suggesting a mechanism of tolerance to multiple stresses that involves calcium influx and stomatal movement regulation.展开更多
Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)t...Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)transcription factoras a heat sensor that regulates stomatal responses by inhibiting open sto-mata 1(OsT1)kinase activity in Arabidopsis.OsT1 induces stomatal closure under heat stress indepen-dently of abscisic acid,and its activity is inhibited in the cytosol by the C-terminus of HSFA1b through intrinsic adenylate cyclase(AC)activity.Arabidopsis HSFA1b could complement an AC-deficient bacte-rium,andthe cyclic AMP produced by HSFA1b could bind to and inhibit OST1kinase activity.This inhibition is relieved under heat stress by HSFA1b translocation into the nucleus,coupling OST1 inhibition with the activation of heat-shock protein genes involved in the perception and signaling of high temperature.Collectively,our study demonstrates that HsFA1b functions as a heat sensor,inhibiting heat stress-induced andOsT1-mediated stomatalclosurethrough itsAC activity.展开更多
Bio-water saving is to increase water use efficiency of crops or crop yield per unit of water input.Plant water use efficiency is determined by photosynthesis and transpiration,for both of which stomata are crucial.St...Bio-water saving is to increase water use efficiency of crops or crop yield per unit of water input.Plant water use efficiency is determined by photosynthesis and transpiration,for both of which stomata are crucial.Stomata are pores on leaf epidermis for both water and carbon dioxide fluxes that are controlled by two major factors:stomatal behavior and density.Stomatal behavior has been the focus of intensive research,while less attention has been paid to stomatal density.Recently,a number of genes controlling stomatal development have been identified.This review summarizes the recent progress on the genes regulating stomatal density,and discusses the role of stomatal density in plant water use efficiency and the possibility to increase plant water use efficiency,hence bio-water saving by genetically manipulating stomatal density.展开更多
Plant responses to abiotic stresses are coordinated by arrays of growth and developmental programs. Gibberellic acid （GA） and abscisic acid （ABA） play critical roles in the developmental programs and environmental...Plant responses to abiotic stresses are coordinated by arrays of growth and developmental programs. Gibberellic acid （GA） and abscisic acid （ABA） play critical roles in the developmental programs and environmental responses, respectively, through complex signaling and metabolism networks. However, crosstalk between the two phytohormones in stress responses remains largely unknown. In this study, we report that GIBBERELLIN-INSENSITIVE DWARF 1 （GID1）, a soluble receptor for GA, regulates stomata[ develop- ment and patterning in rice （Oryza sativa L.）. The gidl mutant showed impaired biosynthesis of endogenous ABA under drought stress conditions, but it exhibited enhanced sensi- tivity to exogenous ABA. Scanning electron microscope and infrared thermal image analysis indicated an increase in the stomatal conductance in the gidl mutant under drought conditions. Interestingly, the gidl mutant had increased levels of chlorophyll and carbohydrates under submergence conditions, and showed enhanced reactive oxygen species （ROS）-scavenging ability and submergence tolerance compared with the wild-type. Further analyses suggested that the function of GID1 in submergence responses is partially dependent on ABA, and GA signaling by GID1 is involved in submergence tolerance by modulating carbohydrate consumption. Taken together, these findings suggest GID1 plays distinct roles in stomatal response and submergence tolerance through both the ABA and GA signaling pathways in rice.展开更多
The initiation of stomatal lineage and subsequent asymmetric divisions in Arabidopsis require the activity of the basic helix-loop-helix transcription factor SPEECHLESS （SPCH）. It has been shown that SPCH controls e...The initiation of stomatal lineage and subsequent asymmetric divisions in Arabidopsis require the activity of the basic helix-loop-helix transcription factor SPEECHLESS （SPCH）. It has been shown that SPCH controls entry into the stomatal lineage as a substrate either of the MITOGEN-ACTIVATED PROTEIN KINASE （MAPK） cascade or GSK3-1ike kinase BRASSlNOSTEROID INSENSITIVE 2 （BIN2）. Here we show that three serine residues of SPCH appear to be the primary phosphorylation targets of Cyclin-Dependent Kinases A;1 （CDKA;1） in vitro, and among them Serine 186 plays a crucial role in stomatal formation. Expression of an SPCH construct harboring a mutation that results in phosphorylation deficiencies on Serine 186 residue failed to rescue stomatal defects in spch null mutants. Expression of a phosphorylation-mimic mutant SPCHS186D complemented stomatal production defects in the transgenic lines harboring the targeted expression of dominant-negative CDKA;1.N146. Therefore, in addition to MAPK- and BIN2-mediated phos- phorylation on SPCH, phosphorylation at Serine 186 is positively required for SPCH function in regulating stomatal development.展开更多
Guard cells are specialized cells forming stomatal pores at the leaf surface for gas exchanges between the plant and the atmosphere. Stomata have been shown to playan important role in plant defense as a part of the i...Guard cells are specialized cells forming stomatal pores at the leaf surface for gas exchanges between the plant and the atmosphere. Stomata have been shown to playan important role in plant defense as a part of the innate immune response. Plants actively close their stomata upon contact with microbes, thereby preventing pathogen entry into the leaves and the subsequent colonization of host tissues. In this review, we present current knowledge of molecular mechanisms and signaling pathways implicated in stomatal defenses, with particular emphasis on plant-bacteria interactions. Stomatal defense responses begin from the perception of pathogen-associated molecular patterns （PAMPs） and activate a signaling cascade involving the production of secondary messengers such as reactive oxygen species, nitric oxide, and calcium for the regulation of plasma membrane ion channels. The analyses on downstream molecular mechanisms implicated in PAMP-triggered stomatal closure have revealed extensive interplays among the components regulating hormonal signaling pathways. We also discuss the strategies deployed by pathogenic bacteria to counteract stomatal immunity through the example of the phytotoxin coronatine.展开更多
The stomatal pores of plant leaves, situated in the epidermis and surrounded by a pair of guard cells, allow CO2 uptake for photosynthesis and water loss through transpiration. Blue light is one of the dominant enviro...The stomatal pores of plant leaves, situated in the epidermis and surrounded by a pair of guard cells, allow CO2 uptake for photosynthesis and water loss through transpiration. Blue light is one of the dominant environmental signals that control stomatal movements in leaves of plants in a natural environment. This blue light response is mediated by blue/UV A light-absorbing phototropins （phots） and cryptochromes （crys）. Red/far-red light-absorbing phytochromes （phys） also play a role in the control of stomatal aperture. The signaling components that link the perception of light signals to the stomatal opening response are largely unknown. This review discusses a few newly discovered nuclear genes, their function with respect to the phot-, cry-, and phy-mediated signal transduction cascades, and possible involve- ment of circadian clock.展开更多
Here the regulatory role of CO during stomatal movement in Vicia faba L.was surveyed.Results indicated that,like hydrogen peroxide(H2O2),CO donor HemaUn induced stomatal closure in dose-and time-dependent manners.Thes...Here the regulatory role of CO during stomatal movement in Vicia faba L.was surveyed.Results indicated that,like hydrogen peroxide(H2O2),CO donor HemaUn induced stomatal closure in dose-and time-dependent manners.These responses were also proven by the addition of gaseous CO aqueous solution with different concentrations,showing the first time that CO and H2O2 exhibit the similar regulation role in the stomatal movement.Moreover,our data showed that ascorbic acid(ASA,an important reducing substrate for H2O2 removal)and diphenylene iodonium(DPI,an inhibitor of the H2O2-generating enzyme NADPH oxidase)not only reversed stomatal closure by CO,but also suppressed the H2O2 fluorescence induced by CO,implying that CO induced-stomatal closure probably involves H2O2 signal.Additionally,the CO/NO scavenger hemoglobin(Hb)and CO specific synthetic inhibitor ZnPPIX,ASA and DPI reversed the darkness-induced stomatal closure and H2O2 fluorescence.These results show that,perhaps like H2O2,the levels of CO in guard cells of V.faba are higher in the dark than in light,HO-1 and NADPH oxidase are the enzyme systems responsible for generating endogenous CO and H2O2 in darkness respectively,and that CO is involved in darkness-induced H2O2 synthesis in V.faba guard cells.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.32272698,32441072,32122081)National Key Research and Development Program of China(Grant No.2023YFF1002000)+4 种基金Liaoning Province Youth Science Foundation A-Class Project(formerly Liaoning Natural Science Foundation Outstanding Youth Project,Grant No.2025-JQ-05)Liaoning Province’s Future Industry Frontier Technology Project(Grant Nos.2025JH2/101330184 and 2025JH2/101330185)National Postdoctoral Program for Innovative Talents(Grant No.BX20250016)Open Project Program of State Key Laboratory of Crop Stress Biology for Arid Areas of China(Grant No.SKLCSRHPKF2025017)HAAFS Science and Technology Innovation Special Project(Grant No.2023KJCXZX-JZS-10).
文摘Stomata are tiny pores on the plant leaf surface that regulate the exchange of water and gases between the plant and the external environment.They are crucial for photosynthesis,water use efficiency(WUE),and the plant’s ability to adapt to environmental changes.Stomatal movement is vital for understanding how plants adapt to environmental stress and optimize resource utilization.Changes in environmental conditions,especially the quality and intensity of light throughout the day,affect stomatal dynamics and diurnal behavior,which in turn impact photosynthetic efficiency and water-use efficiency.In this review,we summarize the biophysical principles and mechanisms of stomatal movement regulated by ion transport at the plasma membrane,vacuolar membrane and metabolic activity through persulfidation or S-nitrosylation modifications.Specifically,we focus on recent progress in the regulation of stomatal movement by different light qualities,and summarize the photochemical and biochemical events underlying photoreceptors as well as the knowledge of novel regulatory functions and signaling in the multilayer control of stomatal movement and environmental adaptation.Furthermore,as rising global temperatures and increased water needs of farming methods are expected to escalate future crop losses,we explore the potential of smart LED lighting and gene editing technology in enhancing photosynthetic efficiency and water-use efficiency,leading to increased crop biomass and higher crop yields.
基金supported by the National Natural Science Foundation of China(No.32271673)5·5 Engineering Research&Innovation Team Project of Beijing Forestry University(No.BLRC2023B06).
文摘Rapid urbanization has contributed to global increases in air pollution derived from urban areas.Unlike natural forests,urban forests are exposed to higher concentrations of airborne pollutants due to the strong urban-suburban-rural pollutant emission gradients.However,there remains a pressing lack of available information pertaining to the urban air pollutionrelated effects on the leaf economics spectrum,anatomical,ultrastructural,and stomatal traits of tree species along an urban-rural gradient.Here,the degree to which urban air pollution impacts the adaption of greening tree species and associated service functions was assessed by sampling five common tree species(Acer pictum,Fraxinus chinensis,Koelreuteria paniculata,Salix babylonica,Sophora japonica)along urban-rural-natural forests in the Beijing metropolitan region of China.These analyses revealed a significant reduction in leaf mass per unit area(-13.4%),leaf thickness(-16.7%),and stomatal area(-27.5%)with increasing proximity to areas of greater air pollution that coincide with significant increases in leaf tissue density(+12.6%),leaf nitrogen content(+10.1%),relative chlorophyll content(+2.7%),and stomatal density(+11.9%).Higher air pollution levels were associated with organelle changes including gradual disintegration of chloroplasts,larger intercellular spaces and apparent starch and plastoglobuli deposition.Air pollutionwas conducive to the strengthening of the trade-off potential and adaptation strategies of trees in urban ecosystems,which are associated with trees with a rapid investment return strategy associated with thick leaves and strong photosynthetic capacity.These results provide strong empirical evidence of the profound air pollution-induced changes in leaf functional traits and adaption ability of urban forest tree species.
基金Supported by the Key Projects in the National Science & Technology Pillar Program during 11th 5-year Plan Period(2006BAI06A11-11)~~
文摘[Objective]This study was to reveal the physiological and ecological mechanism of growth and development of test-tube seedlings.[Methods]Leaf stomata of test-tube seedlings of D.loddigesii and D.candidum at different growth and development stages were observed under scanning electron microscope,and their fluorescence induction response curve was assayed by using modulate fluorometer.[Results] At each growth and development stage,D.loddigesii test-tube seedling has a higher leaf stomatal density over D.candidum,while a lower stomata opening rate.Along with the growth,the size of stomata of both D.loddigesii and D.candidum did not change obviously,but their stoma density increased by 83% and 17.6% respectively.Leaf stomata opening rate reached the highest at the age of 240-day-old.Under the conditions of three settled light intensities,stomatal opening degree of D.loddigesii was increased by the intensity of illumination,the maximum aperture occurred at the light intensity of 54 μmol/m2·s.Given the same culture condition,both the maximum electron transport rate（14 μmol/m2·s）and light saturation point（318 μmol/m2·s）of D.loddigesii test-tube seedling are lower than that of D.candidum（20 μmol/m2·s,483 μmol/m2·s）.Moreover,the potential photosynthetic capacity of D.loddigesii is relatively poor.[Conclusion]The photosynthetic rate varies among different species of Dendrobium,which could be attributed to their different stomatal characteristics.Usually,the light intensity of tissue culture chamber is set up as 27 μmol/（m2·s）,where both D.loddigesii and D.candidum do not acquire an optimal state for their leaf stomatal opening.Considering the characteristics to select suitable culture condition,the stomatal aperture and photosynthetic rate could be enhanced,which can promote the growth and development of test-tube seedlings.
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Science(XDA24010303)the National Natural Science Foundation of China(31770268)+1 种基金the Fundamental Research Funds for the Central Universities(WK2070000091)the University of Science and Technology of China(Start-up fund to S.M.)。
文摘Stomata play critical roles in gas exchange and immunity to pathogens.While many genes regulating early stomatal development up to the production of young guard cells(GCs)have been identified in Arabidopsis,much less is known about how young GCs develop into mature functional stomata.Here we perform a maturomics study on stomata,with“maturomics”defined as omics analysis of the maturation process of a tissue or organ.We develop an integrative scheme to analyze three public stomata-related single-cell RNAseq datasets and identify a list of 586 genes that are specifically up-regulated in all three datasets during stomatal maturation and function formation.The list,termed sc_586,is enriched with known regulators of stomatal maturation and functions.To validate the reliability of the dataset,we selected two candidate G2-like transcription factor genes,MYS1 and MYS2,to investigate their roles in stomata.These two genes redundantly regulate the size and hoop rigidity of mature GCs,and the mys1 mys2 double mutants cause mature GCs with severe defects in regulating their stomatal apertures.Taken together,our results provide a valuable list of genes for studying GC maturation and function formation.
基金Acknowledgments This work was supported by the National Natural Science Foundation of China （NSFC Grant 90717003 to L-J Qu）.
文摘1-Deoxy-D-xylulose-5-phosphate reductoisomerase （DXR） is an important enzyme involved in the 2-C-methyi-D- erythritol-4-phosphate （MEP） pathway which provides the basic five-carbon units for isoprenoid biosynthesis. To investigate the role of the MEP pathway in plant development and metabolism, we carried out detailed analyses on a dxr mutant （GK_215C01） and two DXR transgenic co-suppression fines, OX-DXR-L2 and OX-DXR-L7. We found that the dxr mutant was albino and dwarf. It never bolted, had significantly reduced number of trichomes and most of the stomata could not close normally in the leaves. The two co-suppression lines produced more yellow inflorescences and albino sepals with no trichomes. The transcription levels of genes involved in tricbome initiation were found to be strongly affected, including GLABRA1, TRANSPARENT TESTA GLABROUS 1, TRIPTYCHON and SPINDLY, expression of which is regulated by gibberellic acids （GAs）. Exogenous application of GA3 could partially rescue the dwarf phenotype and the trichome initiation of dxr, whereas exogenous application of abscisic acid （ABA） could rescue the stomata closure defect, suggesting that lower levels of both GA and ABA contribute to the phenotype in the dxr mutants. We further found that genes involved in the biosynthetic pathways of GA and ABA were coordinately regulated. These results indicate that disruption of the plastidial MEP pathway leads to biosynthetic deficiency of photosynthetic pigments, GAs and ABA, and thus the developmental abnormalities, and that the flux from the cytoplasmic mevalonate pathway is not sufficient to rescue the deficiency caused by the blockage of the plastidial MEP pathway. These results reveal a critical role for the MEP biosynthetic pathway in controlling the biosynthesis of isoprenoids.
文摘To observe the regulating effects of vascular endothelial growth factor (VEGF) and angiotensinⅡ (ANG II) on the frog’s pericardium, lymphatic stomata and angiogenesis so as to reveal their effects and mechanism on the mesothelial permeability, lymphatic stoma regulation and myocardial hypertrophy. Methods. VEGF and ANGⅡ were injected into the frog’s peritoneal cavity so as to examine the changes of the pericardial stromata by using transmission electron microscopy, scanning electron microscopy and computerized imaging analysis. Results. Scattered distributed pericardial stomata were found on the parietal pericardium of the frog with a few sinusoid mesothelial cells, whose blood supply was directly from the cardiac chambers flowing into the trabecular spaces of the myocardium (because there are no blood vessels in the myocardium of the frog). The average diameters of the pericardial stomata in VEGF and ANGⅡ groups were 1.50μ m and 1.79μ m respectively, which were much larger than those in the control group (0.72μ m, P Conclusions. VEGF and ANGⅡ could strongly regulate the pericardial stomata by increasing their numbers and openings with larger diameters and higher distribution density. They could also increase the sinusoid areas with the result of the higher permeability of the pericardium, which clearly indicated that VEGF and ANGⅡ could speed up the material transfer of the pericardial cavity and play an important role in preventing myocardial interstitial edema. Yet there was no strong evidence to show the angiogenesis in the myocardium.
文摘The development of the science of cytology and genetics, particularly on cell structure and function provided a breakthrough for breeders and allowed for early selection. Character of stomata density on some commodities was reported as important factor to determine the disease resistance. The research was done for getting information about the differences in the stomata characters influenced on the level of Vascular Streak dieback （VSD） resistance on cocoa. The research was conducted in the Laboratory of Genetics, Gadjah Mada University and leaves samples were conducted in Kendeng Lembu Gardens, PTPN XII. The research used a split plot design with three factors included the type of clones with different levels of VSD disease resistance （PA 191, BL 703 and GS 29）, leaf position （top, middle and base） and leaf age （young and old）. Stomata characters included number of stomata, stomata opening width, stomata wide and stomata diameter were observed. The results showed that the stomata characters in three cacao genotypes with different resistance levels indicated a difference in number of stomata, stomata size, stomata opening width, stomata wide and stomata diameter. Stomata number, stomata opening width and stomata diameter on PA 191 （resistance clone） were lower than the susceptible clones （BL 703 dan GS 29）. The lowest of number and diameter stomata on the base position on the old leaves tissues. Number of stomata, stomata opening width and stomata diameter were estimated role in mechanism of VSD resistance and that were expected could be used as criteria selection to VSD resistance.
基金Supported by the Study Abroad Foundation of Shanxi Province,China( 2010048)CGIAR Challenge Program Project ( GCP) ( G7010.02.01-7)Special Foundation for Talent Introduction And Development of Shanxi Province,China ( 2011)
文摘[ Objective] The study aimed to discuss the relation of leaf stomatal traits to yield and drought resistance of wheat. [ Method] Using the DH population of wheat cultivar Hanxuanl0/Lumai14 as the test object, the relation of leaf stomatal density （SD）, length （SL） and width （ SW）, stomatal conductance （g,）, photosynthetic rate （ Pn ）, transpiration rate （ Tr） to grain yield per plant and index of drought resistance （IDR） on the 10th and 20t＂ day after anthesis under the conditions of drought stress and normal irrigation were discussed by the methods of correlation analysis and path analysis. [ Result] Under the two water conditions, the correlations of these stomatal traits with yield components and IDR were mostly not significant on the 10t＂ day after anthesis, but there were significantly positive correlations between thousand kernel weight （TKW） and these traits on the 20^th day after anthesis. Path analysis showed that g,, Pn and Tt, were main factors affecting yield per plant （YPP） and IDR, and they had stron- ger direct effects on YPP and IDR, while their indirect interaction was also strong. The direct effects of SD, SL and SW on YPP and IDR were small, as well as their indirect action among SD, SL and SW. On the other hand, the correlations between SD and SL were significant, and the correlations of SL with SW, gn, P, and Tt, were extremely significant on the 10th and 20th day after anthesis under the two water conditions. However, the correlations of SD and SL with g,, P,, and Tr changed with water conditions or growth stages, showing that water conditions or growth stages had great effects on the correlations between two traits. Therefore, it is not always a good means to improve stomatal conductance, photosynthetic rate and transpiration rate and hence promote wheat yield by selecting stomatal density and size. [ Conclusion] The research could provide scientific references for revealing the roles of leaf stomatal traits in wheat breeding for drought resistance.
基金supported by Projects 14.00.02.06.P“Development of Methods of Seed Priming of Cereal Grains by the Action of Donors of Gasotransmitters and Compounds with Hormonal Activity”(state registration number of work 0124U000126)III-2-23“Genetic and Epigenetic Mechanisms and Factors of Protective and Adaptive Reactions of Plants”(state registration number of work 0123U101054).
文摘Stomatal closure,which serves to limit water loss,represents one of the most rapid and critical reactions of plants,occurring not only in response to drought but also to a range of other stressors,including salinity,extreme temperatures,heavy metals,gaseous toxicants,and pathogen infection.ABA is considered to be the main regulator of stomatal movements in plants under abiotic stress.In the last two decades,however,the list of plant hormones and other physiologically active substances that affect stomatal status has expanded considerably.It is believed that stomata are regulated by a complex multicomponent network of compounds consisting of hormones and signaling mediators.A special place among them is occupied by gasotransmitters,endogenously synthesized gaseous compounds with signaling functions.The most studied of them are nitrogen monoxide(NO),hydrogen sulfide(H2S),and carbon monoxide(CO).Carbon dioxide(CO_(2)),not yet classified as a classical gasotransmitter,is also considered an important gaseous regulatory molecule.Information has been obtained on the ability of each of these gases to induce stomatal responses in plants.Gasotransmitters are also involved as mediators in stomatal responses induced by various plant hormones and other compounds,particularly ABA,jasmonic and salicylic acids,brassinosteroids,and polyamines.This review examines the functional interactions between gasotransmitters at the level of influencing each other’s synthesis and interactions with other mediators,especially ROS and calcium ions,in their involvement in providing stomatal responses.The latest information on proteins involved in stomatal regulation and undergoing post-translational modification under the action of gasotransmitters,including protein kinases,ion channel proteins,aquaporins,pro-and antioxidant enzymes,is also summarized.The possibilities of practical use of gasotransmitter donors as stress protective agents contributing to the normalization of plant water metabolism are considered.
文摘Preliminary research results indicated that the stomata is one important trait that can be used as an indicator of resistance to vascular streak dieback （VSD） disease. The influence of genotype and environment on the stomatal characters is expected to provide information for specificlocations （habitats） suitable for planting cocoa in particular to avoid VSD attack. The research was conducted at KendengLembu, PTPNXII, East Java. Experimental design used a splitplot design testing： location （altitude） and genotype factors. The location factors, distinguished on the basis of the altitude, were labelled highlands and lowlands. The genotype factors consisted of three clones with different levels of resistance to VSD diseases： PA 191 （tolerant）, BL 703 and GC 29 （susceptible）. The cocoa clones observed were top grafted onto locally available rootstock seedling and planted in 2006-2007. The maintenance of the plants was conducted in accordance with the standards of cocoa cultivation in the PTPN XII. Parameters measured were leaf stomata traits at different positions of the leaf （tip, middle and base）. Characters observed were the number of stomata, opening width of stomata, and diameter of the stomata. The results of the research showed that PA 191 in the lowlands had the lowest number, diameter and opening width of stomata. In contrast, GC 29 in the lowlands showed the highest number of stomata PA 191 and BL 703 in the highlands had a number, diameter and openings width of stomata that was relatively low compared with GC 29. However, the characters of the stomata （number, diameter and openings width of stomata） of the three genotypes in the highland showed a smaller value in each case than in the lowlands. The severity level of VSD attack was greater in the lowlands than in the highlands and PA 191 showed the lowest level of VSD attack at both altitudes.
基金their appreciation to the Researchers Supporting Project number(RSP2024R390)King Saud University,Riyadh,Saudi Arabia and la Direction Générale de la Recherche Scientifique et du Développement Technologique(DGRSDT),Algeria.
文摘The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it essential to better understand this species for its conservation and valorization.Through our work on 7 provenances of Pistacia atlantica distributed across different bioclimates in Algeria and based on 28 quantitative and qualitative leaf,trichome,and stomatal traits,it was revealed that the Atlas pistachio tree exhibits significant ecotypic variability linked to its habitat and a high adaptability to extreme conditions in its environments(aridity and altitude).Indeed,statistical analyses indicate a substantial heterogeneity in the studied characteristics among different ecotypes of P.atlantica.Genetic factors undoubtedly play a primary role in this variability,but environmental factors also exert a remarkable impact on this heterogeneity.Gender also plays a crucial role in this variability.Microphotographs of leaf samples taken under scanning electron microscopy(SEM),such as the density and type of trichomes,and form and position of stomates in the epidermis,can provide an important taxonomic tool for identifying Pistacia species and valuable insights into their adaptation to xeric conditions,thus enabling their use in desertification control projects and the rehabilitation of highly degraded forest environments such as those found in the“Green Dam”initiative.
基金supported by the Natural Science Foundation of China(Grant No.32160490,31860384,32360511,32460510,32170340)National Key Research&Development Program of China Grant(2022YFD1201801)+3 种基金Biological Breeding Project of Gansu Academy of Agricultural Sciences(2024GAAS24)Foundation of the Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations(lzujbky-2022-kb03)Foundation of Science and Technology of Gansu Province(21ZD10NF003-2,22ZD6NA049and24JRRA428)The Fundamental Research Funds for the Central Universities(lzujbky-2023-eyt02).
文摘Maize(Zea mays L.)growth and yield are severely limited by drought stress worldwide.Stomata play crucial roles in transpiration and gas exchange and are thus essential for improving plant water-use efficiency(WUE)to help plants deal with the threat of drought.In this study,we characterized the maize dsd1(decreased stomatal density 1)mutant,which showed defects in stomatal development,including guard mother cell differentiation,subsidiary cell formation and guard cell maturation.DSD1 encodes the basic helix-loop-helix transcription factor INDUCER OF CBF EXPRESSION b(ZmICEb)and is a homolog of ICE1 in Arabidopsis(Arabidopsis thaliana).DSD1/ZmICEb is expressed in stomatal file cells throughout stomatal development and plays a conserved role in stomatal development across maize and Arabidopsis.Mutations in DSD1/ZmICEb dramatically improved drought tolerance and WUE in maize and reduced yield losses under drought conditions.Therefore,DSD1/ZmICEb represents a promising candidate target gene for the genetic improvement of drought tolerance in maize by manipulating stomatal density.
基金supported by grants from the National Natural Science Foundation of China(32370309)the STI 2030-Major Projects(2023ZD040710X)+2 种基金the National Natural Science Foundation of China(31700223)Jiangsu Agricultural Science and Technology Innovation Fund(CX(23)1033)Jiangsu Collaborative Innovation Center for Modern Crop Production and Cyrus Tang Innovation Center for Crop Seed Industry。
文摘Members of the cyclic nucleotide-gated channel(CNGC)proteins are reportedly involved in a variety of biotic and abiotic responses and stomatal movement.However,it is unknown if and how a single member could regulate multiple responses.Here we characterized three closely related CNGC genes in rice,OsCNGC14,OsCNGC15 and OsCNGC16,to determine whether they function in multiple abiotic stresses.The loss-of-function mutants of each of these three genes had reduced calcium ion(Ca^(2+))influx and slower stomatal closure in response to heat,chilling,drought and the stress hormone abscisic acid(ABA).These mutants also had reduced tolerance to heat,chilling and drought compared with the wildtype.Conversely,overexpression of OsCNGC16 led to a more rapid stomatal closure response to stresses and enhanced tolerance to heat,chilling and drought.The tight association of stomatal closure and stress tolerance strongly suggests that tolerance to multiple abiotic stresses conferred by these Os CNGC genes results at least partially from their regulation of stomatal movement.In addition,physical interactions were observed among the three Os CNGC proteins but not with a distantly related CNGC,suggesting the formation of hetero-oligomers among themselves.This study unveils the crucial role of OsCNGC14,15 and 16 proteins in stomatal response and tolerance to multiple stresses,suggesting a mechanism of tolerance to multiple stresses that involves calcium influx and stomatal movement regulation.
基金supported by the National Natural Science Foundation of China(U21A20206 and 32322010)the Education Department of Hainan Province(Hnjg2025ZD-90)the Natural Science Foundation of Henan Province(252300421075).
文摘Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)transcription factoras a heat sensor that regulates stomatal responses by inhibiting open sto-mata 1(OsT1)kinase activity in Arabidopsis.OsT1 induces stomatal closure under heat stress indepen-dently of abscisic acid,and its activity is inhibited in the cytosol by the C-terminus of HSFA1b through intrinsic adenylate cyclase(AC)activity.Arabidopsis HSFA1b could complement an AC-deficient bacte-rium,andthe cyclic AMP produced by HSFA1b could bind to and inhibit OST1kinase activity.This inhibition is relieved under heat stress by HSFA1b translocation into the nucleus,coupling OST1 inhibition with the activation of heat-shock protein genes involved in the perception and signaling of high temperature.Collectively,our study demonstrates that HsFA1b functions as a heat sensor,inhibiting heat stress-induced andOsT1-mediated stomatalclosurethrough itsAC activity.
基金Supported by the Chinese Academy of Sciences(KSCX2-YW-N-012)MOST(2003CB114305)
文摘Bio-water saving is to increase water use efficiency of crops or crop yield per unit of water input.Plant water use efficiency is determined by photosynthesis and transpiration,for both of which stomata are crucial.Stomata are pores on leaf epidermis for both water and carbon dioxide fluxes that are controlled by two major factors:stomatal behavior and density.Stomatal behavior has been the focus of intensive research,while less attention has been paid to stomatal density.Recently,a number of genes controlling stomatal development have been identified.This review summarizes the recent progress on the genes regulating stomatal density,and discusses the role of stomatal density in plant water use efficiency and the possibility to increase plant water use efficiency,hence bio-water saving by genetically manipulating stomatal density.
基金supported by grants from the National Program for Basic Research of China(2012CB114305)the National Program on High Technology Development(2012AA10A303)+1 种基金the National Natural Science Foundation of China(31271316 and J1103510 to Chang Y and Huang F)the National Program of China for Transgenic Research(2011ZX08009-003002,2011ZX08001-003)
文摘Plant responses to abiotic stresses are coordinated by arrays of growth and developmental programs. Gibberellic acid （GA） and abscisic acid （ABA） play critical roles in the developmental programs and environmental responses, respectively, through complex signaling and metabolism networks. However, crosstalk between the two phytohormones in stress responses remains largely unknown. In this study, we report that GIBBERELLIN-INSENSITIVE DWARF 1 （GID1）, a soluble receptor for GA, regulates stomata[ develop- ment and patterning in rice （Oryza sativa L.）. The gidl mutant showed impaired biosynthesis of endogenous ABA under drought stress conditions, but it exhibited enhanced sensi- tivity to exogenous ABA. Scanning electron microscope and infrared thermal image analysis indicated an increase in the stomatal conductance in the gidl mutant under drought conditions. Interestingly, the gidl mutant had increased levels of chlorophyll and carbohydrates under submergence conditions, and showed enhanced reactive oxygen species （ROS）-scavenging ability and submergence tolerance compared with the wild-type. Further analyses suggested that the function of GID1 in submergence responses is partially dependent on ABA, and GA signaling by GID1 is involved in submergence tolerance by modulating carbohydrate consumption. Taken together, these findings suggest GID1 plays distinct roles in stomatal response and submergence tolerance through both the ABA and GA signaling pathways in rice.
文摘The initiation of stomatal lineage and subsequent asymmetric divisions in Arabidopsis require the activity of the basic helix-loop-helix transcription factor SPEECHLESS （SPCH）. It has been shown that SPCH controls entry into the stomatal lineage as a substrate either of the MITOGEN-ACTIVATED PROTEIN KINASE （MAPK） cascade or GSK3-1ike kinase BRASSlNOSTEROID INSENSITIVE 2 （BIN2）. Here we show that three serine residues of SPCH appear to be the primary phosphorylation targets of Cyclin-Dependent Kinases A;1 （CDKA;1） in vitro, and among them Serine 186 plays a crucial role in stomatal formation. Expression of an SPCH construct harboring a mutation that results in phosphorylation deficiencies on Serine 186 residue failed to rescue stomatal defects in spch null mutants. Expression of a phosphorylation-mimic mutant SPCHS186D complemented stomatal production defects in the transgenic lines harboring the targeted expression of dominant-negative CDKA;1.N146. Therefore, in addition to MAPK- and BIN2-mediated phos- phorylation on SPCH, phosphorylation at Serine 186 is positively required for SPCH function in regulating stomatal development.
文摘Guard cells are specialized cells forming stomatal pores at the leaf surface for gas exchanges between the plant and the atmosphere. Stomata have been shown to playan important role in plant defense as a part of the innate immune response. Plants actively close their stomata upon contact with microbes, thereby preventing pathogen entry into the leaves and the subsequent colonization of host tissues. In this review, we present current knowledge of molecular mechanisms and signaling pathways implicated in stomatal defenses, with particular emphasis on plant-bacteria interactions. Stomatal defense responses begin from the perception of pathogen-associated molecular patterns （PAMPs） and activate a signaling cascade involving the production of secondary messengers such as reactive oxygen species, nitric oxide, and calcium for the regulation of plasma membrane ion channels. The analyses on downstream molecular mechanisms implicated in PAMP-triggered stomatal closure have revealed extensive interplays among the components regulating hormonal signaling pathways. We also discuss the strategies deployed by pathogenic bacteria to counteract stomatal immunity through the example of the phytotoxin coronatine.
文摘The stomatal pores of plant leaves, situated in the epidermis and surrounded by a pair of guard cells, allow CO2 uptake for photosynthesis and water loss through transpiration. Blue light is one of the dominant environmental signals that control stomatal movements in leaves of plants in a natural environment. This blue light response is mediated by blue/UV A light-absorbing phototropins （phots） and cryptochromes （crys）. Red/far-red light-absorbing phytochromes （phys） also play a role in the control of stomatal aperture. The signaling components that link the perception of light signals to the stomatal opening response are largely unknown. This review discusses a few newly discovered nuclear genes, their function with respect to the phot-, cry-, and phy-mediated signal transduction cascades, and possible involve- ment of circadian clock.
基金Supported by the Natural Science Research Plan of Shaanxi Provine of China(2005C112).
文摘Here the regulatory role of CO during stomatal movement in Vicia faba L.was surveyed.Results indicated that,like hydrogen peroxide(H2O2),CO donor HemaUn induced stomatal closure in dose-and time-dependent manners.These responses were also proven by the addition of gaseous CO aqueous solution with different concentrations,showing the first time that CO and H2O2 exhibit the similar regulation role in the stomatal movement.Moreover,our data showed that ascorbic acid(ASA,an important reducing substrate for H2O2 removal)and diphenylene iodonium(DPI,an inhibitor of the H2O2-generating enzyme NADPH oxidase)not only reversed stomatal closure by CO,but also suppressed the H2O2 fluorescence induced by CO,implying that CO induced-stomatal closure probably involves H2O2 signal.Additionally,the CO/NO scavenger hemoglobin(Hb)and CO specific synthetic inhibitor ZnPPIX,ASA and DPI reversed the darkness-induced stomatal closure and H2O2 fluorescence.These results show that,perhaps like H2O2,the levels of CO in guard cells of V.faba are higher in the dark than in light,HO-1 and NADPH oxidase are the enzyme systems responsible for generating endogenous CO and H2O2 in darkness respectively,and that CO is involved in darkness-induced H2O2 synthesis in V.faba guard cells.
