The production of invertases by anamorph (A. nidulans) and teleomorph (E. nidulans) was investigated. The best level of extracellular enzymatic production for anomorph was obtained in Khanna medium containing sucrose ...The production of invertases by anamorph (A. nidulans) and teleomorph (E. nidulans) was investigated. The best level of extracellular enzymatic production for anomorph was obtained in Khanna medium containing sucrose as carbon source, whereas for teleomorph the best production was archived using M5 medium containing inulin as carbon source. Despite this, rye flour was selected as carbon source. The extracellular enzyme production was higher for teleomorph than that observed for anomorph for all carbon sources used. The enzyme production was inhibited by the addition of fructose and glucose in the medium containing rye flour as carbon source. The best conditions to recover the higher enzymatic activity were temperature of 54℃ - 62℃ and pH of 4.8 5.6 for both enzymes determined by experimental design (CCRD). The stability of the temperatures at 40℃ and 50℃were similar for both enzymes. The invertases from the anomorph and teleomorph were activated by Mn2+, but the response of each one towards the presence of this cation was different with best activation observed for the anomorph enzyme (+80%). The extracellular enzymes were able to hydrolyze inulin, sucrose and raffinose. However, the affinity was higher for sucrose than inulin. In conclusion, the carbon source assimilation and the invertase production, as well as the enzymes properties, were different for the anomorph and teleomorph mycelia.展开更多
Soluble invertase was purified from pea （Pisum sativum L.） by sequential procedures entailing ammonium sulfate precipitation, DEAE-Sepharose column, Con-A- and Green 19-Sepharose affinity columns, hydroxyapatite col...Soluble invertase was purified from pea （Pisum sativum L.） by sequential procedures entailing ammonium sulfate precipitation, DEAE-Sepharose column, Con-A- and Green 19-Sepharose affinity columns, hydroxyapatite column, ultra-filtration, and Sephacryl 300 gel filtration. The purified soluble acid （SAC） and alkaline （SALK） invertases had a pH optimum of 5.3 and 7.3, respectively. The temperature optimum of two invertases was 37 ℃. The effects of various concentrations of Tris-HCI, HgCI2, and CuSO4 on the activities of the two purified enzymes were examined. Tris-HCI and HgCI2 did not affect SAC activity, whereas 10 mM Tris-HCI and 0.05 mM HgCI2 inhibited SALK activity by about 50%. SAC and SALK were inhibited by 4.8 mM and 0.6 mM CuSO4 by 50%, respectively. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The Kms of SAC and SALK were determined to be 1.8 and 38.6 mM, respectively. The molecular masses of SAC shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting were 22 kDa and 45 kDa. The molecular mass of SALK was 30 kDa. Iso-electric points of the SAC and SALK were estimated to be about pH 7.0 and pH 5.7, respectively.展开更多
: The soluble acid invertase (SAI) and cell wall-bound invertase (CWI) were purified from apple fruit to apparent electrophoretic homogeneity. Based on sequencing, substrate specificity, and immunoblotting assay, the ...: The soluble acid invertase (SAI) and cell wall-bound invertase (CWI) were purified from apple fruit to apparent electrophoretic homogeneity. Based on sequencing, substrate specificity, and immunoblotting assay, the purified enzymes were identified to be two isoforms of acid invertase (β-fructosidase; EC 3.2.1. 26). The SAI and CWI have the same apparent molecular mass with a holoenzyme of molecular mass of 220 kDa composed of 50 kDa subunits. The SAI has a lower Km value for sucrose and higher Km for raffinose compared with CWI. These acid invertases differ from those in other plants in some of their biochemical properties, such as the extremely high Km value for raffinose, no hydrolytic activity for stachyose, and a mixed form of inhibition by fructose to their activity. The antibodies directed against the SAI and CWI recognized, from the crude extract, three polypeptides with a molecular mass of 50, 68, and 30 kDa, respectively. These results provide a substantial basis for the further studies of the acid invertases in apple fruit.展开更多
The present experiment, involving both the in vivo injection of abscislc acid （ABA） Into apple （Malus domestica Brohk.） fruits and the in vivo Incubation of fruit tissues in ABA-contalnlng medium, revealed that AB...The present experiment, involving both the in vivo injection of abscislc acid （ABA） Into apple （Malus domestica Brohk.） fruits and the in vivo Incubation of fruit tissues in ABA-contalnlng medium, revealed that ABA activates both soluble and cell wall-bound acid invertases. Immunoblottlng and enzyme-linked Immunosorbent assays showed that this ABA-induced acid invertase activation is Independent of the amount of enzyme present. The acid Invertase activation induced by ABA is dependent on medium pH, time course, ABA dose, living tissue and developmental stage. Two isomers of cls-（＋）-ABA, （-）-ABA and trans- ABA, had no effect on acid invertases, showing that ABA-induced acid invertase activation is specific to physiologically active cis-（＋）ABA. Protein kinase inhlbltors K252a and H7 as well as acid phosphatase Increased the ABA-Induced effects. These data indicate that ABA specifically activates both soluble and cell wall-bound acid Invertases by a posttranslational mechanism probably Involving reversible protein phosphorylatlon, and this may be one of the mechanisms by which ABA Is Involved In regulating fruit development.展开更多
Cell-wall invertase plays an important role in sucrose partitioning between source and sink organs in higher plants. To investigate the role of cell-wall invertases for seed development in rice （Oryza sativa L.）, cD...Cell-wall invertase plays an important role in sucrose partitioning between source and sink organs in higher plants. To investigate the role of cell-wall invertases for seed development in rice （Oryza sativa L.）, cDNAs of three putative cell- wall invertase genes OsCIN1, OsCIN2 and OsCIN3 were isolated. Semi-quantitative reverse transcription-polymerase chain reaction analysis revealed different expression patterns of the three genes in various rice tissues/organs. In developing caryopses, they exhibited similar temporal expression patterns, expressed highly at the early and middle grain filling stages and gradually declined to low levels afterward. However, the spatial expression patterns of them were very different, with OsCIN1 primarily expressed in the caryopsis coat, OsCIN2 in embryo and endosperm, and OsCIN3 in embryo. Further RNA in situ hybridization analysis revealed that a strong signal of OsCIN2 mRNA was detected in the vascular parenchyma surrounding the xylem of the chalazal vein and the aleurone layer, whereas OsCIN3 transcript was strongly detected in the vascular parenchyma surrounding the phloem of the chalazal vein, cross-cells, the aleurone layer and the nuceUar tissue. These data indicate that the three cell-wall invertase genes play complementary/synergetic roles in assimilate unloading during the grain filling stage. In addition, the cell type-specific expression patterns of OsCIN3 in source leaf blades and anthers were also investigated, and its corresponding physiological roles were discussed.展开更多
oluble solids content(SSC) plays an important role in determining the flavor of tomato fruits. Tomato fruit SSC is transcriptionally regulated via sugar metabolism. Previous studies have predominantly focused on the r...oluble solids content(SSC) plays an important role in determining the flavor of tomato fruits. Tomato fruit SSC is transcriptionally regulated via sugar metabolism. Previous studies have predominantly focused on the role of C2H2-type zinc finger proteins in tomato growth and development. However, the specific regulatory mechanisms of C2H2 in the accumulation of soluble solids in tomato fruits are not fully understood. This study used eight tomato accessions with varying levels of SSC to study the expression of SlC2H2 family genes in red ripe fruits. The levels of SlC2H2-71 expression were found to be significantly reduced in high-SSC accessions compared to low-SSC accessions. Several Slc2h2-71 mutant lines were developed using the CRISPR-Cas9 system, which led to elevated levels of soluble solids, fructose, glucose, malic acid, and citric acid in mature red ripe fruits. However, the sucrose content in the edited Slc2h2-71 mutant lines was generally lower. RNA-seq analysis revealed that fruits from the mutant lines had altered expression of genes related to the sugar and acid metabolic pathways, which was further confirmed by quantitative real-time PCR. Specifically, the expression of SlLIN5 encoding the cell wall invertase(CWIN) was elevated. The yeast one-hybrid(Y1H) assay, 35S::UAS-GUS, dual-luciferase reporter systems and electrophoretic mobility shift assay(EMSA) demonstrated that C2H2-71 regulates tomato sugar metabolism by directly binding to the promoter region of Sl LIN5, culminating in the repression of its transcriptional activity. The activity of acid invertase exhibited a significantly higher level in the SlC2H2-71 knock-out lines compared to the control lines. In summary, the regulation of tomato fruit SSC by C2H2-71 involves the inhibition of SlLIN5 expression.展开更多
[Objective] The aim was to study on effects of "straw returning and ir-returning" and "irrigation with ground water and water in the Yellow River" on changes of enzyme activity in soils under wheat...[Objective] The aim was to study on effects of "straw returning and ir-returning" and "irrigation with ground water and water in the Yellow River" on changes of enzyme activity in soils under wheat at different developmental stages. [Method] Jimai 22, a kind of winter wheat, was made use of in fields to study on effects of "straw returning and ir-returning" and "irrigation with ground water and water in the Yellow River" on changes of enzyme activity in soils under wheat in different developmental stages. [Result] With advancement of developmental stage, urease activity of wheat in the four groups all showed the trend of "increasing-decreasing-increasing" and activities of invertase and phosphatase both changed from increasing to decreasing. In addition, urease activities of soils in wheat roots were improved by straw returning in four developmental stages. Meanwhile, activity of soil enzyme was better promoted by irrigation with ground water than with water in the Yellow River, except in grain-filling stage. Before developmental stage, different processing methods had a significant effect on phosphatase activity, for example, straw returning and ground water significantly enhanced activities of two kinds of phosphatase and promoted P absorption and transferring by plants and microorganisms in jointing stage; activity of acid phosphatase was higher in the group where irrigation with ground water and straw returning were adopted than those in the rest three groups in booting stage. [Conclusion] The research laid a foundation for dynamic relationship among activity of soil enzyme, crop growth and microorganisms.展开更多
Sugar is an important material basis in fruit development,and strawberry fruit flavour and sweetness largely depend on the sugar content and variety.Invertases(INVs)play an important role in the regulation of sugar ac...Sugar is an important material basis in fruit development,and strawberry fruit flavour and sweetness largely depend on the sugar content and variety.Invertases(INVs)play an important role in the regulation of sugar accumulation because they irreversibly catalyse the hydrolysis of sucrose into the corresponding nucleoside diphosphate-glucose,glucose or fructose in fruit.In this work,we provided a comprehensive analysis of the INV gene family in octoploid strawberry(Fragaria×ananassa),including the gene structure,chromosomal locations,conserved domains,and gene evolution and expression profiles during strawberry fruit development.Our study revealed that polyploid events resulted in the abundant amplification(almost three-or four-fold)of the INV gene in the F.×ananassa genome,and these amplified INV genes showed dominant expression in strawberry fruit.More than half of the FaINVs transcripts with low expression had incomplete coding sequences by alternative splicing.Previous studies have shown that cell wall invertases(CWINV)are involved in the regulation of phloem unloading and sink strength establishment.The expression of FaCWINV1 was markedly upregulated during fruit development and strongly expressed in ripe fruit.Moreover,a significant correlation was observed between the total sugar content and the FaCWINV1 expression level.These findings suggest that FaCWINV1 may be involved in sugar accumulation in strawberry fruit.Taken together,the results of our study will be beneficial for further research into the functions of INVs in the regulation of fruit ripening.展开更多
A study was conducted to determine the responses of soil enzymes （invertase, polyphenol oxidase, catalase, and dehydrogenase） to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystem...A study was conducted to determine the responses of soil enzymes （invertase, polyphenol oxidase, catalase, and dehydrogenase） to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences （42°24＇N, 128°28＇E; 738 m in elevation） in the northeast China during 1999-2006. Three treatments of the CO2 enrichment, designed as 500 μmol·mol-1 CO2 open-top chamber （OTC）, ambient control chamber and unchambered field （approx. 370 μmol·mol^-1CO2）, were conducted with Pinus koraiensis and Pinus sylvestriformis tree species. Soil sampling was made and analyzed separately in spring, summer and autumn in 2006 after the soil enzymes were exposed to elevated CO2 concentration （500 μmol·mol^-1） for eight growing seasons. Results showed that, at elevated CO2 concentration （500 μmol·mol^-1）, the activities of invertase （except for the summer samples of P. koraiensis） presented a remarkable decline in all growing seasons, while the activities of dehydrogenase had an increase but only part of the results was remarkable; the activities of polyphenol oxidase in P. sylvestriformis rhizosphere showed a remarkable decrease; the catalase activities increased in spring, while in turn were decline in other seasons. This study also revealed that the soil enzyme activities are significantly correlated with the tree species under the CO2 enhancement.展开更多
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 y...Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices.展开更多
The experiment was designed, via storing potato tubers of cv. E-Potato1 and E-Potato3 indifferent temperatures, to explore the variation patterns of reducing sugar (RS) andtotal sugar (TS) contents and enzyme activiti...The experiment was designed, via storing potato tubers of cv. E-Potato1 and E-Potato3 indifferent temperatures, to explore the variation patterns of reducing sugar (RS) andtotal sugar (TS) contents and enzyme activities that are involved in the pathway ofstarch-sugar metabolism aiming at identifying the main factors that influence the chipcolor. The results showed that low temperature in storage was a main factor thataccelerated the accumulation of RS of the stored tubers and a very significant linearrelationship existed between RS content and chip color index (CCI) of the tubers. Furtheranalysis elucidated that when tubers stored at 4℃, the activities of ADP glucosepyrophosphorylase (AGPase), UDP glucose pyrophosphorylase (UGPase) and sucrose synthase(SuSy) were negatively exponential to the RS content significantly while that of acidinvertase and alkaline invertase was significantly linear to RS content. It suggestedthat these enzymes could play main roles in the cold sweetening of potato tubers throughregulating starch-sugar metabolism.展开更多
Experiments were conducted to study the influences of synthetic bayerite, non crystalline aluminum oxide (N AlOH), goethite, non crystalline iron oxide (N FeOH) and kaolinite on the adsorption, activity, kinetics ...Experiments were conducted to study the influences of synthetic bayerite, non crystalline aluminum oxide (N AlOH), goethite, non crystalline iron oxide (N FeOH) and kaolinite on the adsorption, activity, kinetics and thermal stability of invertase. Adsorption of invertase on iron, aluminum oxides fitted Langmuir equation. The amount of invertase held on the minerals followed the sequence kaolinite > goethite > N AlOH > bayerite > N FeOH. No correlation was found between enzyme adsorption and the specific surface area of minerals examined. The differences in the surface structure of minerals and the arrangement of enzymatic molecules on mineral surfaces led to the different capacities of minerals for enzyme adsorption. The adsorption of invertase on bayerite, N AlOH, goethite, N FeOH and kaolinite was differently affected by pH. The order for the activity of invertase adsorbed on minerals was N FeOH > N AlOH > bayerite > reak goethite > kaolinite. The inhibition effect of minerals on enzyme activity was kaolinite > crystalline oxides > non crystalline oxides. The pH optimum of iron oxide and aluminum oxide invertase complexes was similar to that of free enzyme (pH 4.0), whereas the pH optimum of kaolinite inv ertase complex was one pH unit higher than that of free enzyme. The affinity to substrate and the maximum reaction velocity as well as the thermal stability of combined invertase were lower than those of the free enzyme.展开更多
Global climate models have indicated high probability of drought occurrences in the coming future decades due to the impacts of climate change caused by a mass release of CO2. Thus, climate change regarding elevated a...Global climate models have indicated high probability of drought occurrences in the coming future decades due to the impacts of climate change caused by a mass release of CO2. Thus, climate change regarding elevated ambient CO2 and drought may consequently affect the growth of crops. In this study, plant physiology, soil carbon, and soil enzyme activities were measured to investigate the impacts of elevated C02 and drought stress on a Stagn[c Anthrosol planted with soybean （Glycine ma,z）. Treatments of two CO2 levels, three soil moisture levels, and two soil cover types were established. The results indicated that elevated CO2 and drought stress significantly affected plant physiology. The inhibition of plant physiology by drought stress was mediated via prompted photosynthesis and water use efficiency under elevated CO2 conditions. Elevated CO2 resulted in a longer retention time of dissolved organic carbon （DOC） in soil, probably by improving the soil water effectiveness for organic decomposition and mineralization. Drought stress significantly decreased C：N ratio and microbial biomass carbon （MBC）, but the interactive effects of drought stress and CO2 on them were not significant. Elevated CO2 induced an increase in invertase and catalase activities through stimulated plant root exudation. These results suggested that drought stress had significant negative impacts on plant physiology, soil carbon, and soil enzyme activities, whereas elevated CO2 and plant physiological feedbacks indirectly ameliorated these impacts.展开更多
Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natura...Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natural and high temperatures by using two japonica rice varieties Koshihikari and Sasanishiki. In rice grains, the sucrose synthase activity was higher than that of invertase, which was significantly correlated with starch accumulation rate, indicating that the sucrose synthase played an important role in sucrose degradation and starch synthesis. Under high temperature, the significant increase in grain sucrose content without any increase in fructose and glucose contents, suggested that the high temperature treatment enhanced sucrose accumulation, while diminished sucrose degradation in rice grains. Compared with the control plants, the decrease in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase with high temperature treated plants indicated that the deceleration of sucrose-degradation was related to the decrease in activities of sucrose synthase and invertase.展开更多
Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses o...Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.展开更多
The effect of water deficit on stem reserve mobilization and sink activity in wheat (Triticum aestivum L.) cultivars, viz., C306 (drought tolerant) and PBW343 (drought sensitive) was studied. Drought was maintained in...The effect of water deficit on stem reserve mobilization and sink activity in wheat (Triticum aestivum L.) cultivars, viz., C306 (drought tolerant) and PBW343 (drought sensitive) was studied. Drought was maintained in pot raised plants by withholding irrigation at 95 days after sowing (DAS), i.e. just five days before the initiation of anthesis. Drought induced a significant reduction in mean biomass of all the internodes of sensitive cultivar as compared to those of tolerant one. Mobilized dry matter and mobilization efficiency were observed to be higher in the internodes of tolerant cultivar, both under control and stress conditions, which resulted in enhanced translocation of stem reserves to the grains. Water soluble carbohydrates (WSC), which mainly occur as fructans, were observed to be higher in the internodes of tolerant cultivar than those of sensitive one. When drought was applied, fructans were mobilized more effectively from the internodes of tolerant cultivar. A significantly higher sucrose synthase activity in the grains of tolerant cultivar, under drought conditions, increased the sink strength by unloading the assimilates in the sink, thereby increasing further mobilization of assimilates to the grains. Grains of sensitive cultivar attained maturity much earlier as compared to the tolerant one, both under control and stress conditions. The longer duration of grain maturation in tolerant cultivar supported enhanced mobilization of stem reserves, thus restricting heavy decrease in grain yield, under stress conditions, as compared to the sensitive cultivar. It may, therefore, be concluded that certain characteristics viz., enhanced capability of fructan storage, higher mobilization efficiency, stronger sink activity and longer duration of grain maturation might help the drought tolerant cultivar in coping the stress展开更多
In this study, we produced tomato plants overexpressing an invertase inhibitor gene （Sly-INH） from tomato using a simple and efficient transient transformation system. Compared with control plants, the expression of...In this study, we produced tomato plants overexpressing an invertase inhibitor gene （Sly-INH） from tomato using a simple and efficient transient transformation system. Compared with control plants, the expression of Sly-INH was highly upregulated in Sly-INH overexpressing plants, as indicated by real-time polymerase chain reaction （PCR）. Physiological analysis revealed that Sly-INH inhibited the activity of cell wall invertase （CWIN）, which increased sugar accumulation in tomato fruit. Furthermore, Sly-INH mediated sucrose metabolism by regulating CWIN activity. Our results suggest that invertase activity is potentially regulated by the Sly-INH inhibitor at the post-translational level, and they demonstrate that the transient transformation system is an effective method for determining the functions of genes in tomato.展开更多
The formation of mature and fertile pollen grains, taking place inside the anther, depends on supply of assimilates, in the form of sucrose, provided mainly by the leaves. Data is limited, however, with respect to the...The formation of mature and fertile pollen grains, taking place inside the anther, depends on supply of assimilates, in the form of sucrose, provided mainly by the leaves. Data is limited, however, with respect to the understanding of sucrose metabolism in microspores and the supporting tissues. The aims of the present work were to 1) follow the changes in total and relative concentrations of sucrose, glucose, fructose and starch in the stamen parts and microspores up until anthesis, 2) follow the activities of sucrose-metabolism-related enzymes, in the anther walls fraction and microspores of the crop plant tomato. Sucrose was found to be partially cleaved in the filament, decreasing by more than twofold in the anther wall layers and the locular fluid, and to accumulate in the mature pollen grains, constituting 80% of total soluble sugars. Thus, sucrose was both the starting sugar, supporting microspore development, and the main carbohydrate accumulated at the end of the pollen-development program. The major invertase found to be active in both the anther wall layers and in maturing microspores was cell-wall-bound invertase. High fructokinase 2 and sucrose phosphate synthase activities during pollen maturation coincided with sucrose accumulation. The potential importance of sucrose accumulation during pollen dehydration phase and germination is discussed.展开更多
Six soil enzymes (invertase, acid phosphatase, proteinase, catalase,peroxidase and polyphenoloxidase) were chosen for investigation under different spruce forests withrestoration ages of 4, 10, 16 years and an old-gro...Six soil enzymes (invertase, acid phosphatase, proteinase, catalase,peroxidase and polyphenoloxidase) were chosen for investigation under different spruce forests withrestoration ages of 4, 10, 16 years and an old-growth spruce forest over 400 yearsold in the easternQinghai-Tibet Plateau, China. Results showed that the activities of invertase, phosphatase,proteinase, catalase and peroxidase decreased in newly restored forests except forpholyphenoloxidase. With the development of forests after restoration, the activities of invertase,acid phosphadase, proteinase increased gradually. Our study also indicated that the soil enzymeactivities were associated with surface soils and decreased with depths. This result suggested thatin the earlier restoration stage the application of organic fertilizer may be more effective bysurface addition to soils than deep addition.展开更多
In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(S...In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(Sobic. 006 G160700) have been reported, but their enzymatic properties and functional differences are largely unknown. We combined molecular, biochemical and genomic approaches to investigate their roles in sorghum stem and grain traits. Sb VIN1 and Sb VIN2 showed different expression levels in internodes,leaves, and panicles, indicating that their importance in each organ was different. In an in vitro sucrose hydrolysis assay, proteins of both genes heterologously expressed in Pichia pastoris displayed similar enzyme properties including the same optimum reaction p H(5)and similar Kmfor sucroe(49 mmol L-1 and 45 mmol L-1 for Sb VIN1 and Sb VIN2,respectively). The optimum reaction temperatures of Sb VIN1 and Sb VIN2 were 45 °C and65 °C, respectively. Sb VIN2 showed higher tolerance to high temperature than Sb VIN1. We characterized the sequence variation of these two vacuolar invertase genes in a panel of 216 diverse inbred lines of sweet and grain sorghum and performed gene-based association analysis. Sb VIN1 showed significant associations with stem traits including stem length,stem diameter, internode number, stem fresh weight, and Brix, as well as grain traits including hundred-grain weight and grain width. Significantly associated variation sites were mainly in 5′ upstream and intron regions. Sb VIN2 only associated with grain width and stem water-soluble carbohydrates(WSCs) content. We conclude that the vacuolar invertase genes Sb VIN1 and Sb VIN2 are differently associated with stem and grain traits in sorghum.展开更多
基金supported by grants from the Fundacao de Amparo à Pesquisa do Estado de Sao Paulo(FAPESP)and Conselho de Desenvolvimento Científico e Tecnol-ógico(CNPq).
文摘The production of invertases by anamorph (A. nidulans) and teleomorph (E. nidulans) was investigated. The best level of extracellular enzymatic production for anomorph was obtained in Khanna medium containing sucrose as carbon source, whereas for teleomorph the best production was archived using M5 medium containing inulin as carbon source. Despite this, rye flour was selected as carbon source. The extracellular enzyme production was higher for teleomorph than that observed for anomorph for all carbon sources used. The enzyme production was inhibited by the addition of fructose and glucose in the medium containing rye flour as carbon source. The best conditions to recover the higher enzymatic activity were temperature of 54℃ - 62℃ and pH of 4.8 5.6 for both enzymes determined by experimental design (CCRD). The stability of the temperatures at 40℃ and 50℃were similar for both enzymes. The invertases from the anomorph and teleomorph were activated by Mn2+, but the response of each one towards the presence of this cation was different with best activation observed for the anomorph enzyme (+80%). The extracellular enzymes were able to hydrolyze inulin, sucrose and raffinose. However, the affinity was higher for sucrose than inulin. In conclusion, the carbon source assimilation and the invertase production, as well as the enzymes properties, were different for the anomorph and teleomorph mycelia.
基金supported by grants from the Korea Ocean Research & Development Institute (PE98474)by grants from BioGreen 21 Project funded by Rural Development Administration of Korea (20070401-034-028-009)
文摘Soluble invertase was purified from pea （Pisum sativum L.） by sequential procedures entailing ammonium sulfate precipitation, DEAE-Sepharose column, Con-A- and Green 19-Sepharose affinity columns, hydroxyapatite column, ultra-filtration, and Sephacryl 300 gel filtration. The purified soluble acid （SAC） and alkaline （SALK） invertases had a pH optimum of 5.3 and 7.3, respectively. The temperature optimum of two invertases was 37 ℃. The effects of various concentrations of Tris-HCI, HgCI2, and CuSO4 on the activities of the two purified enzymes were examined. Tris-HCI and HgCI2 did not affect SAC activity, whereas 10 mM Tris-HCI and 0.05 mM HgCI2 inhibited SALK activity by about 50%. SAC and SALK were inhibited by 4.8 mM and 0.6 mM CuSO4 by 50%, respectively. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The Kms of SAC and SALK were determined to be 1.8 and 38.6 mM, respectively. The molecular masses of SAC shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting were 22 kDa and 45 kDa. The molecular mass of SALK was 30 kDa. Iso-electric points of the SAC and SALK were estimated to be about pH 7.0 and pH 5.7, respectively.
文摘: The soluble acid invertase (SAI) and cell wall-bound invertase (CWI) were purified from apple fruit to apparent electrophoretic homogeneity. Based on sequencing, substrate specificity, and immunoblotting assay, the purified enzymes were identified to be two isoforms of acid invertase (β-fructosidase; EC 3.2.1. 26). The SAI and CWI have the same apparent molecular mass with a holoenzyme of molecular mass of 220 kDa composed of 50 kDa subunits. The SAI has a lower Km value for sucrose and higher Km for raffinose compared with CWI. These acid invertases differ from those in other plants in some of their biochemical properties, such as the extremely high Km value for raffinose, no hydrolytic activity for stachyose, and a mixed form of inhibition by fructose to their activity. The antibodies directed against the SAI and CWI recognized, from the crude extract, three polypeptides with a molecular mass of 50, 68, and 30 kDa, respectively. These results provide a substantial basis for the further studies of the acid invertases in apple fruit.
基金Supported by the National Natural Science Foundation of China （30270919, 30471193 and 30330420） and the State Key Basic Research Program of China （2003CBl14302）.
文摘The present experiment, involving both the in vivo injection of abscislc acid （ABA） Into apple （Malus domestica Brohk.） fruits and the in vivo Incubation of fruit tissues in ABA-contalnlng medium, revealed that ABA activates both soluble and cell wall-bound acid invertases. Immunoblottlng and enzyme-linked Immunosorbent assays showed that this ABA-induced acid invertase activation is Independent of the amount of enzyme present. The acid Invertase activation induced by ABA is dependent on medium pH, time course, ABA dose, living tissue and developmental stage. Two isomers of cls-（＋）-ABA, （-）-ABA and trans- ABA, had no effect on acid invertases, showing that ABA-induced acid invertase activation is specific to physiologically active cis-（＋）ABA. Protein kinase inhlbltors K252a and H7 as well as acid phosphatase Increased the ABA-Induced effects. These data indicate that ABA specifically activates both soluble and cell wall-bound acid Invertases by a posttranslational mechanism probably Involving reversible protein phosphorylatlon, and this may be one of the mechanisms by which ABA Is Involved In regulating fruit development.
基金the State Key Basic Research and Development Plan ofChina (2004CB720406)the Innovation Foundation of the Chinese Academyof Sciences (KSCX2-SW-306 and KSCX1-SW-03)the Program for Strategic Scientific Alliances between China and the Netherlands (KNAW-PSA, 04-PSA-BD-04 for P.B.F.O., KNAW-CEP and 04CDP022 for Y.X.)
文摘Cell-wall invertase plays an important role in sucrose partitioning between source and sink organs in higher plants. To investigate the role of cell-wall invertases for seed development in rice （Oryza sativa L.）, cDNAs of three putative cell- wall invertase genes OsCIN1, OsCIN2 and OsCIN3 were isolated. Semi-quantitative reverse transcription-polymerase chain reaction analysis revealed different expression patterns of the three genes in various rice tissues/organs. In developing caryopses, they exhibited similar temporal expression patterns, expressed highly at the early and middle grain filling stages and gradually declined to low levels afterward. However, the spatial expression patterns of them were very different, with OsCIN1 primarily expressed in the caryopsis coat, OsCIN2 in embryo and endosperm, and OsCIN3 in embryo. Further RNA in situ hybridization analysis revealed that a strong signal of OsCIN2 mRNA was detected in the vascular parenchyma surrounding the xylem of the chalazal vein and the aleurone layer, whereas OsCIN3 transcript was strongly detected in the vascular parenchyma surrounding the phloem of the chalazal vein, cross-cells, the aleurone layer and the nuceUar tissue. These data indicate that the three cell-wall invertase genes play complementary/synergetic roles in assimilate unloading during the grain filling stage. In addition, the cell type-specific expression patterns of OsCIN3 in source leaf blades and anthers were also investigated, and its corresponding physiological roles were discussed.
基金supported by the grants from the National Key Research & Development Plan of China (2022YFF10030022022YFD1200502)+5 种基金the National Natural Science Foundation of China (32372696)the Wuhan Biological Breeding Major Project, China (2022021302024852)the HZAU–AGIS Cooperation Fund, China (SZYJY2023022)the Funds for High Quality Development of Hubei Seed Industry, China (HBZY2023B004)the Hubei Agriculture Research System, China (2024HBSTX4-06)the Funds of National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, China (Horti3Y-2024-008)。
文摘oluble solids content(SSC) plays an important role in determining the flavor of tomato fruits. Tomato fruit SSC is transcriptionally regulated via sugar metabolism. Previous studies have predominantly focused on the role of C2H2-type zinc finger proteins in tomato growth and development. However, the specific regulatory mechanisms of C2H2 in the accumulation of soluble solids in tomato fruits are not fully understood. This study used eight tomato accessions with varying levels of SSC to study the expression of SlC2H2 family genes in red ripe fruits. The levels of SlC2H2-71 expression were found to be significantly reduced in high-SSC accessions compared to low-SSC accessions. Several Slc2h2-71 mutant lines were developed using the CRISPR-Cas9 system, which led to elevated levels of soluble solids, fructose, glucose, malic acid, and citric acid in mature red ripe fruits. However, the sucrose content in the edited Slc2h2-71 mutant lines was generally lower. RNA-seq analysis revealed that fruits from the mutant lines had altered expression of genes related to the sugar and acid metabolic pathways, which was further confirmed by quantitative real-time PCR. Specifically, the expression of SlLIN5 encoding the cell wall invertase(CWIN) was elevated. The yeast one-hybrid(Y1H) assay, 35S::UAS-GUS, dual-luciferase reporter systems and electrophoretic mobility shift assay(EMSA) demonstrated that C2H2-71 regulates tomato sugar metabolism by directly binding to the promoter region of Sl LIN5, culminating in the repression of its transcriptional activity. The activity of acid invertase exhibited a significantly higher level in the SlC2H2-71 knock-out lines compared to the control lines. In summary, the regulation of tomato fruit SSC by C2H2-71 involves the inhibition of SlLIN5 expression.
文摘[Objective] The aim was to study on effects of "straw returning and ir-returning" and "irrigation with ground water and water in the Yellow River" on changes of enzyme activity in soils under wheat at different developmental stages. [Method] Jimai 22, a kind of winter wheat, was made use of in fields to study on effects of "straw returning and ir-returning" and "irrigation with ground water and water in the Yellow River" on changes of enzyme activity in soils under wheat in different developmental stages. [Result] With advancement of developmental stage, urease activity of wheat in the four groups all showed the trend of "increasing-decreasing-increasing" and activities of invertase and phosphatase both changed from increasing to decreasing. In addition, urease activities of soils in wheat roots were improved by straw returning in four developmental stages. Meanwhile, activity of soil enzyme was better promoted by irrigation with ground water than with water in the Yellow River, except in grain-filling stage. Before developmental stage, different processing methods had a significant effect on phosphatase activity, for example, straw returning and ground water significantly enhanced activities of two kinds of phosphatase and promoted P absorption and transferring by plants and microorganisms in jointing stage; activity of acid phosphatase was higher in the group where irrigation with ground water and straw returning were adopted than those in the rest three groups in booting stage. [Conclusion] The research laid a foundation for dynamic relationship among activity of soil enzyme, crop growth and microorganisms.
基金This work was funded by the Major Project for Breeding New Varieties of Jiangsu Province,China(PZCZ201721)the National Horticulture Germplasm Resources Center,China(NHGRC2020-NH16)the National Crop Germplasm Resources Protection of the Ministry of Agriculture and Rural Affairs of China(19200361).
文摘Sugar is an important material basis in fruit development,and strawberry fruit flavour and sweetness largely depend on the sugar content and variety.Invertases(INVs)play an important role in the regulation of sugar accumulation because they irreversibly catalyse the hydrolysis of sucrose into the corresponding nucleoside diphosphate-glucose,glucose or fructose in fruit.In this work,we provided a comprehensive analysis of the INV gene family in octoploid strawberry(Fragaria×ananassa),including the gene structure,chromosomal locations,conserved domains,and gene evolution and expression profiles during strawberry fruit development.Our study revealed that polyploid events resulted in the abundant amplification(almost three-or four-fold)of the INV gene in the F.×ananassa genome,and these amplified INV genes showed dominant expression in strawberry fruit.More than half of the FaINVs transcripts with low expression had incomplete coding sequences by alternative splicing.Previous studies have shown that cell wall invertases(CWINV)are involved in the regulation of phloem unloading and sink strength establishment.The expression of FaCWINV1 was markedly upregulated during fruit development and strongly expressed in ripe fruit.Moreover,a significant correlation was observed between the total sugar content and the FaCWINV1 expression level.These findings suggest that FaCWINV1 may be involved in sugar accumulation in strawberry fruit.Taken together,the results of our study will be beneficial for further research into the functions of INVs in the regulation of fruit ripening.
基金This research was supported by National Basic Research Program of China (No.2002CB412502)Project of Key Pro-gram of the National Science Foundation of China (No.90411020)Natural Science Foundation of China (No.30400051)
文摘A study was conducted to determine the responses of soil enzymes （invertase, polyphenol oxidase, catalase, and dehydrogenase） to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences （42°24＇N, 128°28＇E; 738 m in elevation） in the northeast China during 1999-2006. Three treatments of the CO2 enrichment, designed as 500 μmol·mol-1 CO2 open-top chamber （OTC）, ambient control chamber and unchambered field （approx. 370 μmol·mol^-1CO2）, were conducted with Pinus koraiensis and Pinus sylvestriformis tree species. Soil sampling was made and analyzed separately in spring, summer and autumn in 2006 after the soil enzymes were exposed to elevated CO2 concentration （500 μmol·mol^-1） for eight growing seasons. Results showed that, at elevated CO2 concentration （500 μmol·mol^-1）, the activities of invertase （except for the summer samples of P. koraiensis） presented a remarkable decline in all growing seasons, while the activities of dehydrogenase had an increase but only part of the results was remarkable; the activities of polyphenol oxidase in P. sylvestriformis rhizosphere showed a remarkable decrease; the catalase activities increased in spring, while in turn were decline in other seasons. This study also revealed that the soil enzyme activities are significantly correlated with the tree species under the CO2 enhancement.
基金Project supported by the Knowledge Innovation Project of the Chinese Academy of Sciences (Nos. KZCX3-SW-339 and KSCX1-07) the Ministry of Science and Technology of China (No. 2001CCB00600).
文摘Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices.
基金This research was supported by the National Natural Science Foundation of China(30270842)the Key Project of 10th Five-Year Plan of Hubei Province,China.
文摘The experiment was designed, via storing potato tubers of cv. E-Potato1 and E-Potato3 indifferent temperatures, to explore the variation patterns of reducing sugar (RS) andtotal sugar (TS) contents and enzyme activities that are involved in the pathway ofstarch-sugar metabolism aiming at identifying the main factors that influence the chipcolor. The results showed that low temperature in storage was a main factor thataccelerated the accumulation of RS of the stored tubers and a very significant linearrelationship existed between RS content and chip color index (CCI) of the tubers. Furtheranalysis elucidated that when tubers stored at 4℃, the activities of ADP glucosepyrophosphorylase (AGPase), UDP glucose pyrophosphorylase (UGPase) and sucrose synthase(SuSy) were negatively exponential to the RS content significantly while that of acidinvertase and alkaline invertase was significantly linear to RS content. It suggestedthat these enzymes could play main roles in the cold sweetening of potato tubers throughregulating starch-sugar metabolism.
文摘Experiments were conducted to study the influences of synthetic bayerite, non crystalline aluminum oxide (N AlOH), goethite, non crystalline iron oxide (N FeOH) and kaolinite on the adsorption, activity, kinetics and thermal stability of invertase. Adsorption of invertase on iron, aluminum oxides fitted Langmuir equation. The amount of invertase held on the minerals followed the sequence kaolinite > goethite > N AlOH > bayerite > N FeOH. No correlation was found between enzyme adsorption and the specific surface area of minerals examined. The differences in the surface structure of minerals and the arrangement of enzymatic molecules on mineral surfaces led to the different capacities of minerals for enzyme adsorption. The adsorption of invertase on bayerite, N AlOH, goethite, N FeOH and kaolinite was differently affected by pH. The order for the activity of invertase adsorbed on minerals was N FeOH > N AlOH > bayerite > reak goethite > kaolinite. The inhibition effect of minerals on enzyme activity was kaolinite > crystalline oxides > non crystalline oxides. The pH optimum of iron oxide and aluminum oxide invertase complexes was similar to that of free enzyme (pH 4.0), whereas the pH optimum of kaolinite inv ertase complex was one pH unit higher than that of free enzyme. The affinity to substrate and the maximum reaction velocity as well as the thermal stability of combined invertase were lower than those of the free enzyme.
基金supported by the National Natural Science Foundation of China (No.51309053)the Fundamental Research Funds for the Central Universities-Donghua University (DHU) Distinguished Young Professor Program, China (No.B201310)
文摘Global climate models have indicated high probability of drought occurrences in the coming future decades due to the impacts of climate change caused by a mass release of CO2. Thus, climate change regarding elevated ambient CO2 and drought may consequently affect the growth of crops. In this study, plant physiology, soil carbon, and soil enzyme activities were measured to investigate the impacts of elevated C02 and drought stress on a Stagn[c Anthrosol planted with soybean （Glycine ma,z）. Treatments of two CO2 levels, three soil moisture levels, and two soil cover types were established. The results indicated that elevated CO2 and drought stress significantly affected plant physiology. The inhibition of plant physiology by drought stress was mediated via prompted photosynthesis and water use efficiency under elevated CO2 conditions. Elevated CO2 resulted in a longer retention time of dissolved organic carbon （DOC） in soil, probably by improving the soil water effectiveness for organic decomposition and mineralization. Drought stress significantly decreased C：N ratio and microbial biomass carbon （MBC）, but the interactive effects of drought stress and CO2 on them were not significant. Elevated CO2 induced an increase in invertase and catalase activities through stimulated plant root exudation. These results suggested that drought stress had significant negative impacts on plant physiology, soil carbon, and soil enzyme activities, whereas elevated CO2 and plant physiological feedbacks indirectly ameliorated these impacts.
文摘Dynamic changes of sucrose, fructose, glucose contents and differences in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase in rice grain after flowering stage were studied under natural and high temperatures by using two japonica rice varieties Koshihikari and Sasanishiki. In rice grains, the sucrose synthase activity was higher than that of invertase, which was significantly correlated with starch accumulation rate, indicating that the sucrose synthase played an important role in sucrose degradation and starch synthesis. Under high temperature, the significant increase in grain sucrose content without any increase in fructose and glucose contents, suggested that the high temperature treatment enhanced sucrose accumulation, while diminished sucrose degradation in rice grains. Compared with the control plants, the decrease in activities of sucrose synthase, vacuolar invertase, and cell wall bound invertase with high temperature treated plants indicated that the deceleration of sucrose-degradation was related to the decrease in activities of sucrose synthase and invertase.
基金supported by the National Key Research and Development Program of China (2017YFD0300408)the Major Research Projects of Anhui (202003b06020021)the Graduate Innovation Fund of Anhui Agricultural University (2020 ysj-5)。
文摘Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.
文摘The effect of water deficit on stem reserve mobilization and sink activity in wheat (Triticum aestivum L.) cultivars, viz., C306 (drought tolerant) and PBW343 (drought sensitive) was studied. Drought was maintained in pot raised plants by withholding irrigation at 95 days after sowing (DAS), i.e. just five days before the initiation of anthesis. Drought induced a significant reduction in mean biomass of all the internodes of sensitive cultivar as compared to those of tolerant one. Mobilized dry matter and mobilization efficiency were observed to be higher in the internodes of tolerant cultivar, both under control and stress conditions, which resulted in enhanced translocation of stem reserves to the grains. Water soluble carbohydrates (WSC), which mainly occur as fructans, were observed to be higher in the internodes of tolerant cultivar than those of sensitive one. When drought was applied, fructans were mobilized more effectively from the internodes of tolerant cultivar. A significantly higher sucrose synthase activity in the grains of tolerant cultivar, under drought conditions, increased the sink strength by unloading the assimilates in the sink, thereby increasing further mobilization of assimilates to the grains. Grains of sensitive cultivar attained maturity much earlier as compared to the tolerant one, both under control and stress conditions. The longer duration of grain maturation in tolerant cultivar supported enhanced mobilization of stem reserves, thus restricting heavy decrease in grain yield, under stress conditions, as compared to the sensitive cultivar. It may, therefore, be concluded that certain characteristics viz., enhanced capability of fructan storage, higher mobilization efficiency, stronger sink activity and longer duration of grain maturation might help the drought tolerant cultivar in coping the stress
基金supported by the National Natural Science Foundation of China(Nos.31372054 and 30971999)the State Key Laboratory of Plant Physiology and Biochemistry Open Project of China(No.SKLPPBKF1404)
文摘In this study, we produced tomato plants overexpressing an invertase inhibitor gene （Sly-INH） from tomato using a simple and efficient transient transformation system. Compared with control plants, the expression of Sly-INH was highly upregulated in Sly-INH overexpressing plants, as indicated by real-time polymerase chain reaction （PCR）. Physiological analysis revealed that Sly-INH inhibited the activity of cell wall invertase （CWIN）, which increased sugar accumulation in tomato fruit. Furthermore, Sly-INH mediated sucrose metabolism by regulating CWIN activity. Our results suggest that invertase activity is potentially regulated by the Sly-INH inhibitor at the post-translational level, and they demonstrate that the transient transformation system is an effective method for determining the functions of genes in tomato.
文摘The formation of mature and fertile pollen grains, taking place inside the anther, depends on supply of assimilates, in the form of sucrose, provided mainly by the leaves. Data is limited, however, with respect to the understanding of sucrose metabolism in microspores and the supporting tissues. The aims of the present work were to 1) follow the changes in total and relative concentrations of sucrose, glucose, fructose and starch in the stamen parts and microspores up until anthesis, 2) follow the activities of sucrose-metabolism-related enzymes, in the anther walls fraction and microspores of the crop plant tomato. Sucrose was found to be partially cleaved in the filament, decreasing by more than twofold in the anther wall layers and the locular fluid, and to accumulate in the mature pollen grains, constituting 80% of total soluble sugars. Thus, sucrose was both the starting sugar, supporting microspore development, and the main carbohydrate accumulated at the end of the pollen-development program. The major invertase found to be active in both the anther wall layers and in maturing microspores was cell-wall-bound invertase. High fructokinase 2 and sucrose phosphate synthase activities during pollen maturation coincided with sucrose accumulation. The potential importance of sucrose accumulation during pollen dehydration phase and germination is discussed.
文摘Six soil enzymes (invertase, acid phosphatase, proteinase, catalase,peroxidase and polyphenoloxidase) were chosen for investigation under different spruce forests withrestoration ages of 4, 10, 16 years and an old-growth spruce forest over 400 yearsold in the easternQinghai-Tibet Plateau, China. Results showed that the activities of invertase, phosphatase,proteinase, catalase and peroxidase decreased in newly restored forests except forpholyphenoloxidase. With the development of forests after restoration, the activities of invertase,acid phosphadase, proteinase increased gradually. Our study also indicated that the soil enzymeactivities were associated with surface soils and decreased with depths. This result suggested thatin the earlier restoration stage the application of organic fertilizer may be more effective bysurface addition to soils than deep addition.
基金the National Natural Science Foundation of China(No.31471570,No.31461143023)Ministry of Science and Technology of the People's Republic of China(2015BAD15B03).
文摘In higher plants, vacuolar invertases play essential roles in sugar metabolism, organ development, and sink strength. In sorghum(Sorghum bicolor), two vacuolar invertase genes,Sb VIN1(Sobic. 004 G004800) and Sb VIN2(Sobic. 006 G160700) have been reported, but their enzymatic properties and functional differences are largely unknown. We combined molecular, biochemical and genomic approaches to investigate their roles in sorghum stem and grain traits. Sb VIN1 and Sb VIN2 showed different expression levels in internodes,leaves, and panicles, indicating that their importance in each organ was different. In an in vitro sucrose hydrolysis assay, proteins of both genes heterologously expressed in Pichia pastoris displayed similar enzyme properties including the same optimum reaction p H(5)and similar Kmfor sucroe(49 mmol L-1 and 45 mmol L-1 for Sb VIN1 and Sb VIN2,respectively). The optimum reaction temperatures of Sb VIN1 and Sb VIN2 were 45 °C and65 °C, respectively. Sb VIN2 showed higher tolerance to high temperature than Sb VIN1. We characterized the sequence variation of these two vacuolar invertase genes in a panel of 216 diverse inbred lines of sweet and grain sorghum and performed gene-based association analysis. Sb VIN1 showed significant associations with stem traits including stem length,stem diameter, internode number, stem fresh weight, and Brix, as well as grain traits including hundred-grain weight and grain width. Significantly associated variation sites were mainly in 5′ upstream and intron regions. Sb VIN2 only associated with grain width and stem water-soluble carbohydrates(WSCs) content. We conclude that the vacuolar invertase genes Sb VIN1 and Sb VIN2 are differently associated with stem and grain traits in sorghum.
