Stomata are epidermal pores that are essential for water evaporation and gas exchange in plants.Stomatal development is orchestrated by intrinsic developmental programs,hormonal controls,and environmental cues.The ste...Stomata are epidermal pores that are essential for water evaporation and gas exchange in plants.Stomatal development is orchestrated by intrinsic developmental programs,hormonal controls,and environmental cues.The steroid hormone brassinosteroid(BR)inhibits stomatal lineage progression by regulating BIN2 and BSL proteins in leaves.Notably,BR is known to promote stomatal development in hypocotyls as opposed to leaves;however,its molecular mechanism remains elusive.Here,we show that BR signaling has a dual regulatory role in controlling stomatal development in Arabidopsis hypocotyls.We found that brassinolide(BL;the most active BR)regulates stomatal development differently in a concentration-dependent manner.At low and moderate concentrations,BL promoted stomatal formation by upregulating the expression of SPEECHLESS(SPCH)and its target genes independently of BIN2 regulation.In contrast,high concentrations of BL and bikinin,which is a specific inhibitor of BIN2 and its homologs,significantly reduced stomatal formation.Genetic analyses revealed that BIN2 regulates stomatal development in hypocotyls through molecular mechanisms distinct from the regulatory mechanism of the cotyledons.In hypocotyls,BIN2 promoted stomatal development by inactivating BZR1,which suppresses the expression of SPCH and its target genes.Taken together,our results suggest that BR precisely coordinates the stomatal development of hypocotyls using an antagonistic control of SPCH expression via BZR1-dependent and BZR1-independent transcriptional regulation.展开更多
The balance between stem cell division and differentiation is crucial for flexible organ development.In Ara-bidopsis leaves,the fate of meristemoids,which exhibit stem cell characteristics,is tightly regulated by mult...The balance between stem cell division and differentiation is crucial for flexible organ development.In Ara-bidopsis leaves,the fate of meristemoids,which exhibit stem cell characteristics,is tightly regulated by multiple intrinsic developmental signals and environmental factors.KiN1o,the catalytic subunit of the su-crose non-fermenting 1-related protein kinase 1(SnRK1)complex,has been shown to preferentially localize in the nucleus ofmeristemoids,where it phosphorylates and stabilizes the SPEECHLESS transcrip-tion factor,thereby promoting stomatal development.However,the regulatory mechanism governing the nuclear localization of KiN1o in meristemoids remains unclear.Here,we demonstrate that brassinosteroid(BR)inhibits KIN10's nuclear localization by modulating KINβ2 through BR-INSENSITIVE2(BIN2)-mediated phosphorylation.In meristemoids,KIN1o is predominantly nuclear,while KINp2 is mainly cytosolic.Inter-fering with the nuclear localization of KIN10 or enhancing the membrane association of KiNp2 impairs sto-matal development and leads to excessive epidermal cell proliferation.Cell biology and biochemical ana-lyses reveal that BR signaling could inhibit KIN10 nuclear localization by enhancing KIN2 membrane association,while BIN2 interacts with and phosphorylates KINp2 to reduce its membrane association and its interaction with KiN1o.Taken together,these findings suggest that the precise regulation of the subcellular localization of the SnRK1 complex,at least in part by BR signaling,is critical for meristemoid differentiation and stomatal development.展开更多
The stomatal pores of plant leaves control gas exchange with the environment.Stomatal development is prevised regulated by both internal genetic programs and environmental cues.Among various environmental factors,ligh...The stomatal pores of plant leaves control gas exchange with the environment.Stomatal development is prevised regulated by both internal genetic programs and environmental cues.Among various environmental factors,light regulation of stomata formation has been extensively studied in Arabidopsis.In this review,we summarize recent advances in the genetic control of stomata development and its regulation by light.We also present a comparative analysis of the conserved and diverged stomatal regulatory networks between Arabidopsis and cereal grasses.Lastly,we provide our perspectives on manipulation of the stomata density on plant leaves for the purpose of breeding crops that are better adapted to the adverse environment and high-density planting conditions.展开更多
Cryptochromes are blue light photoreceptors that mediate various light responses in plants and mammals. The heterotrimeric G-protein is known to regulate various physiological processes in plants and mammals. In Arabi...Cryptochromes are blue light photoreceptors that mediate various light responses in plants and mammals. The heterotrimeric G-protein is known to regulate various physiological processes in plants and mammals. In Arabidopsis, cryptochrome 1(CRY1) and the G-protein β subunit AGB1 act antagonistically to regulate stomatal development.The molecular mechanism by which CRY1 and AGB1 regulate this process remains unknown.Here, we show that Arabidopsis CRY1 acts partially through AGB1, and AGB1 acts through SPEECHLESS(SPCH), a master transcription factor that drives stomatal initiation and proliferation, to regulate stomatal development. We demonstrate that AGB1 physically interacts with SPCH to block the b HLH DNA-binding domain of SPCH and inhibit its DNA-binding activity. Moreover, we demonstrate that photoexcited CRY1 represses the interaction of AGB1 with SPCH to release AGB1 inhibition of SPCH DNA-binding activity, leading to the expression of SPCH-target genes promoting stomatal development. Taken together, our results suggest that the mechanism by which CRY1 promotes stomatal development involves positive regulation of the DNA-binding activity of SPCH mediated by CRY1 inhibition of the AGB1-SPCH interaction. We propose that the antagonistic regulation of SPCH DNA-binding activity by CRY1 and AGB1 may allow plants to balance light and G-protein signaling and optimize stomatal density and pattern.展开更多
During the terminal stage of stomatal development,the R2 R3-MYB transcription factors FOUR LIPS(FLP/MYB124) and MYB88 limit guard mother cell division by repressing the transcript levels of multiple cell-cycle genes. ...During the terminal stage of stomatal development,the R2 R3-MYB transcription factors FOUR LIPS(FLP/MYB124) and MYB88 limit guard mother cell division by repressing the transcript levels of multiple cell-cycle genes. In Arabidopsis thaliana possessing the weak allele flp-1, an extra guard mother cell division results in two stomata having direct contact.Here, we identified an ethylmethane sulfonatemutagenized mutant, flp-1 xs01 c, which exhibited more severe defects than flp-1 alone, producing gianttumor-like cell clusters. XS01 C, encoding F-BOX STRESS-INDUCED 4(FBS4), is preferentially expressed in epidermal stomatal precursor cells.Overexpressing FBS4 rescued the defective stomatal phenotypes of flp-1 xs01 c and flp-1 mutants. The deletion or substitution of a conserved residue(Proline166) within the F-box domain of FBS4 abolished or reduced, respectively, its interaction with Arabidopsis Skp1-Like1(ASK1), the core subunit of the Skp1/Cullin/F-box E3 ubiquitin ligase complex. Furthermore, the FBS4 protein physically interacted with CYCA2;3 and induced its degradation through the ubiquitin-26 S proteasome pathway. Thus, in addition to the known transcriptional pathway, the terminal symmetric division in stomatal development is ensured at the post-translational level, such as through the ubiquitination of target proteins recognized by the stomatal lineage F-box protein FBS4.展开更多
Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors aff...Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.展开更多
In Arabidopsis thaliana L., stomata are produced through a series of divisions including asymmetric and symmetric divisions. Asymmetric entry division of meristemoid mother cellproduces two daughter cells, the smal er...In Arabidopsis thaliana L., stomata are produced through a series of divisions including asymmetric and symmetric divisions. Asymmetric entry division of meristemoid mother cellproduces two daughter cells, the smal er meristemoid and the larger sister cell, a stomatal lineage ground cell（SLGC）. Stomatal lineage ground cells can differentiate into epidermal pavement cells but have the potential to divide asymmetrical y, spacing divisions, to create satel ite meristemoids. Peptide ligands and TOO MANY MOUTHS （TMM） and ERECTA family receptors regulate the initiation of stomatal lineages, activity, and orientation of spacing divisions. Here, we reported that a natural mutant 28y displayed an increased stomatal density and index. Using map-based cloning, we identified mutation in ARGONAUTE1 （AGO1） as the cause of 28y phenotypes. Time-lapse tracing of stomatal lineage cells reveals that stomatal overproduction in 28y is caused by the excessive asymmetric spacing division of SLGCs.Further genetic results demonstrated that AGO1 acts down-stream of TMM and negatively regulates the SPCH transcripts, but in a brassinosteroid-independent manner. Upregulation of AGAMOUS-LIKE16 （AGL16） in 28y mutants suggests that AGO1 is required to restrict AGL16-mediated stomatal spacing divisions, an miRNA pathway in addition to ligand-receptor signaling modules.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(Ministry of Science and ICT or Ministry of Education)(2021R1A2C1006617 and RS-2024-00407469 to T.-W.K.)supported by the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Ministry of Education(2023R1A6C101A009 to T.-K.P.)the research fund of Hanyang University(HY-202200000003024 to T.-K.P.)。
文摘Stomata are epidermal pores that are essential for water evaporation and gas exchange in plants.Stomatal development is orchestrated by intrinsic developmental programs,hormonal controls,and environmental cues.The steroid hormone brassinosteroid(BR)inhibits stomatal lineage progression by regulating BIN2 and BSL proteins in leaves.Notably,BR is known to promote stomatal development in hypocotyls as opposed to leaves;however,its molecular mechanism remains elusive.Here,we show that BR signaling has a dual regulatory role in controlling stomatal development in Arabidopsis hypocotyls.We found that brassinolide(BL;the most active BR)regulates stomatal development differently in a concentration-dependent manner.At low and moderate concentrations,BL promoted stomatal formation by upregulating the expression of SPEECHLESS(SPCH)and its target genes independently of BIN2 regulation.In contrast,high concentrations of BL and bikinin,which is a specific inhibitor of BIN2 and its homologs,significantly reduced stomatal formation.Genetic analyses revealed that BIN2 regulates stomatal development in hypocotyls through molecular mechanisms distinct from the regulatory mechanism of the cotyledons.In hypocotyls,BIN2 promoted stomatal development by inactivating BZR1,which suppresses the expression of SPCH and its target genes.Taken together,our results suggest that BR precisely coordinates the stomatal development of hypocotyls using an antagonistic control of SPCH expression via BZR1-dependent and BZR1-independent transcriptional regulation.
基金supported by grants from the National Natural Science Foundation of China(32270351 to C.H.,32325006 to M.-Y.B.,U24A20389 to M.-Y.B.,and 32461160287 to M.-Y.B.)Agricultural Variety Improvement Project of Shandong Province(2022LZGC001 to M.-Y.B.and 2024LZGC007 to M.F.)Science and Technology Department of Shandong Province(ZR2022YQ20 to C.H.).
文摘The balance between stem cell division and differentiation is crucial for flexible organ development.In Ara-bidopsis leaves,the fate of meristemoids,which exhibit stem cell characteristics,is tightly regulated by multiple intrinsic developmental signals and environmental factors.KiN1o,the catalytic subunit of the su-crose non-fermenting 1-related protein kinase 1(SnRK1)complex,has been shown to preferentially localize in the nucleus ofmeristemoids,where it phosphorylates and stabilizes the SPEECHLESS transcrip-tion factor,thereby promoting stomatal development.However,the regulatory mechanism governing the nuclear localization of KiN1o in meristemoids remains unclear.Here,we demonstrate that brassinosteroid(BR)inhibits KIN10's nuclear localization by modulating KINβ2 through BR-INSENSITIVE2(BIN2)-mediated phosphorylation.In meristemoids,KIN1o is predominantly nuclear,while KINp2 is mainly cytosolic.Inter-fering with the nuclear localization of KIN10 or enhancing the membrane association of KiNp2 impairs sto-matal development and leads to excessive epidermal cell proliferation.Cell biology and biochemical ana-lyses reveal that BR signaling could inhibit KIN10 nuclear localization by enhancing KIN2 membrane association,while BIN2 interacts with and phosphorylates KINp2 to reduce its membrane association and its interaction with KiN1o.Taken together,these findings suggest that the precise regulation of the subcellular localization of the SnRK1 complex,at least in part by BR signaling,is critical for meristemoid differentiation and stomatal development.
基金H.W.is supported by a project sponsored by the Education Department of Guangdong Province(2018KQNCX022).
文摘The stomatal pores of plant leaves control gas exchange with the environment.Stomatal development is prevised regulated by both internal genetic programs and environmental cues.Among various environmental factors,light regulation of stomata formation has been extensively studied in Arabidopsis.In this review,we summarize recent advances in the genetic control of stomata development and its regulation by light.We also present a comparative analysis of the conserved and diverged stomatal regulatory networks between Arabidopsis and cereal grasses.Lastly,we provide our perspectives on manipulation of the stomata density on plant leaves for the purpose of breeding crops that are better adapted to the adverse environment and high-density planting conditions.
基金This work was supported by The National Natural Science Foundation of China grants(31530085,31900609,31900207,32000183)The National Key Research and Development Program of China grant(2017YFA0503802)The Science and Technology Commission of Shanghai Municipality grant(18DZ2260500)。
文摘Cryptochromes are blue light photoreceptors that mediate various light responses in plants and mammals. The heterotrimeric G-protein is known to regulate various physiological processes in plants and mammals. In Arabidopsis, cryptochrome 1(CRY1) and the G-protein β subunit AGB1 act antagonistically to regulate stomatal development.The molecular mechanism by which CRY1 and AGB1 regulate this process remains unknown.Here, we show that Arabidopsis CRY1 acts partially through AGB1, and AGB1 acts through SPEECHLESS(SPCH), a master transcription factor that drives stomatal initiation and proliferation, to regulate stomatal development. We demonstrate that AGB1 physically interacts with SPCH to block the b HLH DNA-binding domain of SPCH and inhibit its DNA-binding activity. Moreover, we demonstrate that photoexcited CRY1 represses the interaction of AGB1 with SPCH to release AGB1 inhibition of SPCH DNA-binding activity, leading to the expression of SPCH-target genes promoting stomatal development. Taken together, our results suggest that the mechanism by which CRY1 promotes stomatal development involves positive regulation of the DNA-binding activity of SPCH mediated by CRY1 inhibition of the AGB1-SPCH interaction. We propose that the antagonistic regulation of SPCH DNA-binding activity by CRY1 and AGB1 may allow plants to balance light and G-protein signaling and optimize stomatal density and pattern.
基金supported by grants from the National Natural Science Foundation of China to J.L.(31771515 and 31970804)K.Y.(31871377 and 32070723)。
文摘During the terminal stage of stomatal development,the R2 R3-MYB transcription factors FOUR LIPS(FLP/MYB124) and MYB88 limit guard mother cell division by repressing the transcript levels of multiple cell-cycle genes. In Arabidopsis thaliana possessing the weak allele flp-1, an extra guard mother cell division results in two stomata having direct contact.Here, we identified an ethylmethane sulfonatemutagenized mutant, flp-1 xs01 c, which exhibited more severe defects than flp-1 alone, producing gianttumor-like cell clusters. XS01 C, encoding F-BOX STRESS-INDUCED 4(FBS4), is preferentially expressed in epidermal stomatal precursor cells.Overexpressing FBS4 rescued the defective stomatal phenotypes of flp-1 xs01 c and flp-1 mutants. The deletion or substitution of a conserved residue(Proline166) within the F-box domain of FBS4 abolished or reduced, respectively, its interaction with Arabidopsis Skp1-Like1(ASK1), the core subunit of the Skp1/Cullin/F-box E3 ubiquitin ligase complex. Furthermore, the FBS4 protein physically interacted with CYCA2;3 and induced its degradation through the ubiquitin-26 S proteasome pathway. Thus, in addition to the known transcriptional pathway, the terminal symmetric division in stomatal development is ensured at the post-translational level, such as through the ubiquitination of target proteins recognized by the stomatal lineage F-box protein FBS4.
基金supported by the National Natural Science Foundation of China (31571615)the earmarked fund for China Agriculture Research System (CARS-04-PS19)。
文摘Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.
基金supported by grants from the National Natural Science Foundation of China, 30971652 and 31271463 (J. L.), 31071198 (K. Y.)Hundred Talents Program andKSCX2-YW-N- 073 from the Chinese Academy of Sciences
文摘In Arabidopsis thaliana L., stomata are produced through a series of divisions including asymmetric and symmetric divisions. Asymmetric entry division of meristemoid mother cellproduces two daughter cells, the smal er meristemoid and the larger sister cell, a stomatal lineage ground cell（SLGC）. Stomatal lineage ground cells can differentiate into epidermal pavement cells but have the potential to divide asymmetrical y, spacing divisions, to create satel ite meristemoids. Peptide ligands and TOO MANY MOUTHS （TMM） and ERECTA family receptors regulate the initiation of stomatal lineages, activity, and orientation of spacing divisions. Here, we reported that a natural mutant 28y displayed an increased stomatal density and index. Using map-based cloning, we identified mutation in ARGONAUTE1 （AGO1） as the cause of 28y phenotypes. Time-lapse tracing of stomatal lineage cells reveals that stomatal overproduction in 28y is caused by the excessive asymmetric spacing division of SLGCs.Further genetic results demonstrated that AGO1 acts down-stream of TMM and negatively regulates the SPCH transcripts, but in a brassinosteroid-independent manner. Upregulation of AGAMOUS-LIKE16 （AGL16） in 28y mutants suggests that AGO1 is required to restrict AGL16-mediated stomatal spacing divisions, an miRNA pathway in addition to ligand-receptor signaling modules.
