Castor bean(Ricinus communis L.)is an economically important non-edible oilseed crop.Its seed oils are rich in hydroxy fatty acid,which are highly valuable with a wide range of industrial applications.Sucrose transpor...Castor bean(Ricinus communis L.)is an economically important non-edible oilseed crop.Its seed oils are rich in hydroxy fatty acid,which are highly valuable with a wide range of industrial applications.Sucrose transportation is critical in regulating the growth,development and oilseed yield in castor bean.The transporters or carriers(SUTs or SUCs)play a central role in orchestrating sucrose allocation and aiding in plant adaptation to diverse stresses.In this study,based on castor bean genome,three RcSUCs(RcSUC2,RcSUC3 and RcSUC4)were identified and characterized.The expressional profiles of RcSUCs in different tissues such as leaf,stem,root,phloem and seed tissues exhibited a distinct divergence of gene expression,suggesting that the functions of RcSUC2,RcSUC3 and RcSUC4 are differentiated into long or short-distance transportation among tissues.Additionally,under abiotic stresses including hot temperature,low temperature,drought and salt stresses,the sugar allocation among leaf,stem and roots was tested.The expressional changes of Rc SUCs in leaf,stem and root tissues were associated with sugar transportation and allocation.Taken together,the differential expression of Rc SUCs among tissues responsing to abiotic stress suggested functional differences in sucrose transport and redistribution in different tissues.This study is helpful to understand the physiological and molecular mechanisms of sucrose transportation and allocation among tissues in heterotrophic oilseeds,and could provide clues for genetic improvement and optimization of cultivation practices.展开更多
Herbivorous insects change the metabolism of the plant during their attack. Our study reports the changes in the expression pattern of sucrose transporters in response to the infestation of aphids at different time in...Herbivorous insects change the metabolism of the plant during their attack. Our study reports the changes in the expression pattern of sucrose transporters in response to the infestation of aphids at different time intervals. Results showed a significant enhancement in the expression pattern for six out of nine sucrose transporters in response to aphid infestation, followed by suppression after some point. During an earlier time point of infestation, the expressions of sucrose transporters were enhanced probably to compensate for the energy requirements of the damaged cell. However, suppression of sucrose transporters at a later stage may be a defense strategy of the plant to repel the aphids because at a later stage of infestation, aphids become a secondary sink. To complement our assumption, we performed aphid infestation choice and reproductive performance tests in the null mutant of one of the transporters, SUC2, which was compromised in phloem loading of sucrose. Results showed that the mutant was less preferable to aphid for choice as well as reproduction performance.展开更多
In higher plants, sugars （mainly sucrose） are produced by photosynthetically assimilated carbon in mesophyll cells of leaves and translocated to heterotrophic organs to ensure plant growth and devel- opment. Sucrose...In higher plants, sugars （mainly sucrose） are produced by photosynthetically assimilated carbon in mesophyll cells of leaves and translocated to heterotrophic organs to ensure plant growth and devel- opment. Sucrose transporters, or sucrose carriers （SUCs）, play an important role in the long-distance transportation of sucrose from source organs to sink organs, thereby affecting crop yield and quality. The identification, characterization, and molecular function analysis of sucrose transporter genes have been reported for monocot and dicot plants. However, no relevant study has been reported on sucrose transporter genes in Brassica rapa vat. rapa, a cruciferous root crop used mainly as vegetables and fodder. We identified and cloned 12 sucrose transporter genes from turnips, named BrrSUC1.1 to BrrSUCB.2 according to the SUC gene sequences of B. rapa pekinensis. We constructed a phylogenetic tree and analyzed conserved motifs for all 12 sucrose transporter genes identified. Real-time quantitative poly- merase chain reaction was conducted to understand the expression levels of SUC genes in different tissues and developmental phases of the turnip. These findings add to our understanding of the genetics and physiology of sugar transport during taproot formation in turnips.展开更多
In this work, the enzymatic hydrolysis reaction of sucrose through invertase under unsteady-state conditions has been investigated. The aim is to evaluate the inhibition phenomena influence on the reaction rate and, t...In this work, the enzymatic hydrolysis reaction of sucrose through invertase under unsteady-state conditions has been investigated. The aim is to evaluate the inhibition phenomena influence on the reaction rate and, then, on the concentration and temperature profiles by simulating the process in a tubular reactor, varying the enzyme concentration and the reactant mixture velocity. The transport phenomena considered during the enzymatic hydrolysis process have been described by means of unsteady-state momentum, mass and energy balance equations, taking into account molecular and convective transport and generation terms. Interpretation and discussion of the results obtained by FEM resolution of PDEs involved allow to understand the relevance of the operating parameters.展开更多
An experiment was conducted to study the effects of sucrose supplementation, insulin injection, and resting period prior to slaughtering on meat quality in sheep exposed to stressful transportation. Fifty four local s...An experiment was conducted to study the effects of sucrose supplementation, insulin injection, and resting period prior to slaughtering on meat quality in sheep exposed to stressful transportation. Fifty four local sheep （10 to 12 months of age） with body weight （BW） ranged from 14 to 1 7 kg. The experimental sheep were assigned into a completely randomized design with a 2 × 3 × 3 factorial arrangement with 3 replications. The first factor was two levels of sucrose supplementation （0 and 6 g/kg BW）, the second factor was three levels of insulin injection after transportation （0, 0.3 and 0.6 IU/kg BW）, while the third factor was three duration time of resting period （2, 4 and 6 h prior to slaughtering）. Parameters measured were rectal temperature and heart rate, body weight, carcass percentage, meat pH, water holding capacity, meat tenderness, cooking loss and meat color. The results of the experiment showed that sheep after transportation had higher rectal temperature and heart rate, indicated that sheep supplemented with sucrose after transportation has a lower meat pH and cooking loss. The longer resting period prior to slaughtering has the lower body weight, but has higher carcass percentage. However, the treatments did not influence water holding capacity, meat tenderness and meat color. It was concluded that sucrose supplementation, insulin injection, and resting period prior to slaughtering in sheep exposed to stressful transportation could improve meat quality.展开更多
基金supported by the National Natural Science Foundation of China(31661143002 and 31771839)。
文摘Castor bean(Ricinus communis L.)is an economically important non-edible oilseed crop.Its seed oils are rich in hydroxy fatty acid,which are highly valuable with a wide range of industrial applications.Sucrose transportation is critical in regulating the growth,development and oilseed yield in castor bean.The transporters or carriers(SUTs or SUCs)play a central role in orchestrating sucrose allocation and aiding in plant adaptation to diverse stresses.In this study,based on castor bean genome,three RcSUCs(RcSUC2,RcSUC3 and RcSUC4)were identified and characterized.The expressional profiles of RcSUCs in different tissues such as leaf,stem,root,phloem and seed tissues exhibited a distinct divergence of gene expression,suggesting that the functions of RcSUC2,RcSUC3 and RcSUC4 are differentiated into long or short-distance transportation among tissues.Additionally,under abiotic stresses including hot temperature,low temperature,drought and salt stresses,the sugar allocation among leaf,stem and roots was tested.The expressional changes of Rc SUCs in leaf,stem and root tissues were associated with sugar transportation and allocation.Taken together,the differential expression of Rc SUCs among tissues responsing to abiotic stress suggested functional differences in sucrose transport and redistribution in different tissues.This study is helpful to understand the physiological and molecular mechanisms of sucrose transportation and allocation among tissues in heterotrophic oilseeds,and could provide clues for genetic improvement and optimization of cultivation practices.
文摘Herbivorous insects change the metabolism of the plant during their attack. Our study reports the changes in the expression pattern of sucrose transporters in response to the infestation of aphids at different time intervals. Results showed a significant enhancement in the expression pattern for six out of nine sucrose transporters in response to aphid infestation, followed by suppression after some point. During an earlier time point of infestation, the expressions of sucrose transporters were enhanced probably to compensate for the energy requirements of the damaged cell. However, suppression of sucrose transporters at a later stage may be a defense strategy of the plant to repel the aphids because at a later stage of infestation, aphids become a secondary sink. To complement our assumption, we performed aphid infestation choice and reproductive performance tests in the null mutant of one of the transporters, SUC2, which was compromised in phloem loading of sucrose. Results showed that the mutant was less preferable to aphid for choice as well as reproduction performance.
基金supported by Major Program of National Natural Science Foundation of China (31590820,31590823)
文摘In higher plants, sugars （mainly sucrose） are produced by photosynthetically assimilated carbon in mesophyll cells of leaves and translocated to heterotrophic organs to ensure plant growth and devel- opment. Sucrose transporters, or sucrose carriers （SUCs）, play an important role in the long-distance transportation of sucrose from source organs to sink organs, thereby affecting crop yield and quality. The identification, characterization, and molecular function analysis of sucrose transporter genes have been reported for monocot and dicot plants. However, no relevant study has been reported on sucrose transporter genes in Brassica rapa vat. rapa, a cruciferous root crop used mainly as vegetables and fodder. We identified and cloned 12 sucrose transporter genes from turnips, named BrrSUC1.1 to BrrSUCB.2 according to the SUC gene sequences of B. rapa pekinensis. We constructed a phylogenetic tree and analyzed conserved motifs for all 12 sucrose transporter genes identified. Real-time quantitative poly- merase chain reaction was conducted to understand the expression levels of SUC genes in different tissues and developmental phases of the turnip. These findings add to our understanding of the genetics and physiology of sugar transport during taproot formation in turnips.
文摘In this work, the enzymatic hydrolysis reaction of sucrose through invertase under unsteady-state conditions has been investigated. The aim is to evaluate the inhibition phenomena influence on the reaction rate and, then, on the concentration and temperature profiles by simulating the process in a tubular reactor, varying the enzyme concentration and the reactant mixture velocity. The transport phenomena considered during the enzymatic hydrolysis process have been described by means of unsteady-state momentum, mass and energy balance equations, taking into account molecular and convective transport and generation terms. Interpretation and discussion of the results obtained by FEM resolution of PDEs involved allow to understand the relevance of the operating parameters.
文摘An experiment was conducted to study the effects of sucrose supplementation, insulin injection, and resting period prior to slaughtering on meat quality in sheep exposed to stressful transportation. Fifty four local sheep （10 to 12 months of age） with body weight （BW） ranged from 14 to 1 7 kg. The experimental sheep were assigned into a completely randomized design with a 2 × 3 × 3 factorial arrangement with 3 replications. The first factor was two levels of sucrose supplementation （0 and 6 g/kg BW）, the second factor was three levels of insulin injection after transportation （0, 0.3 and 0.6 IU/kg BW）, while the third factor was three duration time of resting period （2, 4 and 6 h prior to slaughtering）. Parameters measured were rectal temperature and heart rate, body weight, carcass percentage, meat pH, water holding capacity, meat tenderness, cooking loss and meat color. The results of the experiment showed that sheep after transportation had higher rectal temperature and heart rate, indicated that sheep supplemented with sucrose after transportation has a lower meat pH and cooking loss. The longer resting period prior to slaughtering has the lower body weight, but has higher carcass percentage. However, the treatments did not influence water holding capacity, meat tenderness and meat color. It was concluded that sucrose supplementation, insulin injection, and resting period prior to slaughtering in sheep exposed to stressful transportation could improve meat quality.
文摘夜间补光已成为设施蔬菜生产的重要手段,但多采用强光,耗能大、成本高,而夜间弱光补光对蔬菜生产的影响尚不清楚。为探讨夜间弱光补光对番茄生长和源库间蔗糖转运的影响,以Micro Tom番茄为材料,从植株4叶1心时期到果实绿熟期,以不补光为对照(CK),每天关灯1 h后进行4 h 15(SL15)和30μmol·m^(-2)·s^(-1)(SL30)低于光补偿点的两种补光处理。结果表明,与CK相比,SL15和SL30两个处理均显著提高番茄株高、茎粗和鲜质量;补光明显改善了根系形态,显著增加了总根长、总表面积和根尖数;补光促进开花,表现为开花株数和总开花数显著高于CK。以上生理指标SL15和SL30两个处理之间没有显著差异。与CK相比,SL15处理显著降低了成熟叶片和茎(源)的蔗糖含量,提高了果实和根系(库)的蔗糖含量,促进了蔗糖转运基因SUT1、SUT4、SWEET10b、SWEET11b和SWEET14在叶片、茎、果实和根系不同程度地上调表达,但叶片、茎、果实和根系4个器官总体的蔗糖含量没有显著差异。此外,SL15处理显著提高了叶片、茎、果实和根系4个器官中与蔗糖转运相关激素脱落酸的含量及其合成和信号标志基因NCED1、AAO3和ABI5的表达量。综上所述,夜间弱光补光可促进番茄生长及源库间蔗糖转运,研究结果为推广夜间弱光补光、降低补光成本、促进设施蔬菜高效绿色发展提供了新思路。
