[Objective] This study aimed to analyze the effects of temperature on the expression of AGPase isoform genes in rice endosperm during milk stage. [Method] Different temperature treatments （33 and 25 ℃ of daily mean ...[Objective] This study aimed to analyze the effects of temperature on the expression of AGPase isoform genes in rice endosperm during milk stage. [Method] Different temperature treatments （33 and 25 ℃ of daily mean temperature for high and normal temperature treatments, respectively） and the real-time fluorescence quantitative PCR （ FQPCR） were used to analyze the expression patterns of seven isoforms （AGPS1, AGPS2a, AGPS2b, AGPL1, AGPL2, AGPL3 and AGPL4） of ADPglucose pyrophosphorylase （AGPase） which was the key enzyme in starch synthesis and metabolism in rice endosperm of two rice varieties Teqing and Thai Fragrant Rice. [Result] The AGPase isoforms AGPS2b, AGPL2 and AGPL3 had much higher expression than the other four isoforms, thus they were thought to be the main expression patterns of AGPase in rice endosperm. The relative expressions of AGPL2 was the highest among all the isoforms. The relative expressions of AGPS2b, AGPL2 and AGPL3 were higher in the normal temperature treatment than in the high temperature treatment in both rice varieties. The relative expression of the three enzyme genes in milk stages in Teqing was higher than those in Thai Fragrant Rice under different temperature treatments. [Conclusion] This study provides a theoretical basis for further use of molecular biology techniques to cultivate stable high-quality rice varieties.展开更多
Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 （indica） and Nipponbare （japon...Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 （indica） and Nipponbare （japonica） as materials. Under shading treatments, the starch, amylose and sucrose contents decreased, while ADP-glucose pyrophosphorylase （ADPGPPase） activity only changed a little, soluble starch synthase activity and granule bound starch synthase activity decreased, soluble starch branching enzyme （SSBE, Q-enzyme） activity and granule bound starch branching enzyme （GBSBE, Q-enzyme） activity increased, and starch debranching enzyme （DBE, R-enzyme） activity varied with varieties. Correlation analyses showed that the changes of starch content were positively and significantly correlated with the changes of sucrose content in the weak light. Both ADPGPPase activity and SSBE activity were positively and significantly correlated with starch accumulation rate. It was implied that the decline of starch synthase activities was related to the decrease of starch content and the increase of the activity of starch branching enzyme played an important role in the decrease of the ratio of amylose to the total starch under the weak light.展开更多
Under-development of pea (Pisum sativum L.) seeds in normally developed pods, resulting in “unfilled pods”, has been a serious problem in the greenhouse cultivation in Wakayama Prefecture, one of the major regions o...Under-development of pea (Pisum sativum L.) seeds in normally developed pods, resulting in “unfilled pods”, has been a serious problem in the greenhouse cultivation in Wakayama Prefecture, one of the major regions of pea cultivation in Japan. This phenomenon appears to be induced by low temperature and low solar irradiation during pea growing season. This study examined the relationship between this seed under-development and sucrose-to-starch metabolism in developing seeds and pods after flowering. The starch content, ADP-glucose pyrophosphorylase (AGPase) and sucrose synthase activities of a pea cultivar, Kishuusui, were monitored through seed development in shading-treatment plot and in control plot. Results showed that the present treatment induced the depression of starch accumulation and AGPase activity in developing seeds compared with control, which might cause the occurrence of under-development of seeds and unfilled pods. Surplus carbohydrates from source organs might be stored in pod walls, as expected from higher starch level and AGPase activity in treated pod walls. The necessity of thermostable AGPase variants in pea to prevent the unfilled-pod problem was discussed.展开更多
采用田间小区试验研究“推荐配比”(N:P2O5:K2O比率为190:90:100 kg hm-2)、“高氮量配比”(N:P2O5:K2O比率为210:90:100 kg hm-2)、“低氮量配比”(N:P2O5:K2O比率为170:90:100 kg hm-2)以及“常规配比”(N:P2O5:K2O比率为216:112.5:20...采用田间小区试验研究“推荐配比”(N:P2O5:K2O比率为190:90:100 kg hm-2)、“高氮量配比”(N:P2O5:K2O比率为210:90:100 kg hm-2)、“低氮量配比”(N:P2O5:K2O比率为170:90:100 kg hm-2)以及“常规配比”(N:P2O5:K2O比率为216:112.5:202.5 kg hm-2)4种氮、磷、钾配比施肥对饲用稻威优198蔗糖合成酶(SUS)、腺苷二磷酸焦磷酸化酶(AGPase)、硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及产量和糙米蛋白质的影响。结果表明:“推荐配比”能提高不同生育时期水稻功能叶(旗叶)和粒籽中碳、氮代谢关键酶的活性,这些关键酶活性的变化显著影响水稻产量和糙米全氮以及蛋白氮的含量。统计(P0.05)结果证实“推荐配比”能提高水稻产量达到8200 kg hm-2,与“常规配比”相比产量提高了24.81%;“推荐配比”糙米全氮和蛋白氮含量分别达到22.70 g kg-1和21.98 g kg-1,与“常规配比”相比差异显著,并且其全氮和蛋白氮含量分别提高17.01%,18.38%。展开更多
The dynamic changes of the activities of enzymes involving in starch biosynthesis, including ADP-glucose pyrophosphorylase (AGPase), soluble starch synthases (SSS), starch branching enzyme (SBE) and starch debranching...The dynamic changes of the activities of enzymes involving in starch biosynthesis, including ADP-glucose pyrophosphorylase (AGPase), soluble starch synthases (SSS), starch branching enzyme (SBE) and starch debranching enzymes (DBE) were studied, and changes of fine structure of amy- lopectin were characterized by isoamylase treatment during rice grain development, using trans anti-waxy gene rice plants. The relationships between the activities of those key enzymes were also analyzed. The amylose synthesis was significantly inhibited in transgenic Wanjing 9522, but the total starch content and final grain weight were less affected as compared with those of non-transgenic Wanjing 9522 rice cultivar. Analyses on the changes of activities of enzymes involving in starch bio- synthesis showed that different enzyme activities were expressed differently during rice endosperm development. Soluble starch synthase is relatively highly expressed in earlier stage of endosperm de- velopment, whilst maximal expression of granule-bound starch synthase (GBSS) occurred in mid-stage of endosperm development. No obvious differences in changes of the activities of AGPase and SBE between two rice cultivars investigated, except the DBEs. Distribution patterns of branches of amy- lopectin changed continually during the development of rice grains and varied between two rice culti- vars. It was suggested that amylopectin synthesis be prior to the synthesis of amylose and different enzymes have different roles in controlling syntheses of branches of amylopectin.展开更多
基金Supported by Special Project for Breeding and Cultivation of GMO Varieties of Ministry of Agriculture (2011ZX08001-001, 2011ZX08001-004)Major Science and Technology Program of Hunan, China (2011FJ1002-2)+1 种基金Natural Science Foundation of Hunan, China (09JJ3046 )Science and Technology Innovation Program of Hunan Academy of Agricultural Sciences (2009hnnkycx17)~~
文摘[Objective] This study aimed to analyze the effects of temperature on the expression of AGPase isoform genes in rice endosperm during milk stage. [Method] Different temperature treatments （33 and 25 ℃ of daily mean temperature for high and normal temperature treatments, respectively） and the real-time fluorescence quantitative PCR （ FQPCR） were used to analyze the expression patterns of seven isoforms （AGPS1, AGPS2a, AGPS2b, AGPL1, AGPL2, AGPL3 and AGPL4） of ADPglucose pyrophosphorylase （AGPase） which was the key enzyme in starch synthesis and metabolism in rice endosperm of two rice varieties Teqing and Thai Fragrant Rice. [Result] The AGPase isoforms AGPS2b, AGPL2 and AGPL3 had much higher expression than the other four isoforms, thus they were thought to be the main expression patterns of AGPase in rice endosperm. The relative expressions of AGPL2 was the highest among all the isoforms. The relative expressions of AGPS2b, AGPL2 and AGPL3 were higher in the normal temperature treatment than in the high temperature treatment in both rice varieties. The relative expression of the three enzyme genes in milk stages in Teqing was higher than those in Thai Fragrant Rice under different temperature treatments. [Conclusion] This study provides a theoretical basis for further use of molecular biology techniques to cultivate stable high-quality rice varieties.
文摘Dynamic changes of starch, amylose, sucrose contents and the activities of starch synthesis enzymes under shading treatments alter flowering were studied using two rice varieties IR72 （indica） and Nipponbare （japonica） as materials. Under shading treatments, the starch, amylose and sucrose contents decreased, while ADP-glucose pyrophosphorylase （ADPGPPase） activity only changed a little, soluble starch synthase activity and granule bound starch synthase activity decreased, soluble starch branching enzyme （SSBE, Q-enzyme） activity and granule bound starch branching enzyme （GBSBE, Q-enzyme） activity increased, and starch debranching enzyme （DBE, R-enzyme） activity varied with varieties. Correlation analyses showed that the changes of starch content were positively and significantly correlated with the changes of sucrose content in the weak light. Both ADPGPPase activity and SSBE activity were positively and significantly correlated with starch accumulation rate. It was implied that the decline of starch synthase activities was related to the decrease of starch content and the increase of the activity of starch branching enzyme played an important role in the decrease of the ratio of amylose to the total starch under the weak light.
文摘Under-development of pea (Pisum sativum L.) seeds in normally developed pods, resulting in “unfilled pods”, has been a serious problem in the greenhouse cultivation in Wakayama Prefecture, one of the major regions of pea cultivation in Japan. This phenomenon appears to be induced by low temperature and low solar irradiation during pea growing season. This study examined the relationship between this seed under-development and sucrose-to-starch metabolism in developing seeds and pods after flowering. The starch content, ADP-glucose pyrophosphorylase (AGPase) and sucrose synthase activities of a pea cultivar, Kishuusui, were monitored through seed development in shading-treatment plot and in control plot. Results showed that the present treatment induced the depression of starch accumulation and AGPase activity in developing seeds compared with control, which might cause the occurrence of under-development of seeds and unfilled pods. Surplus carbohydrates from source organs might be stored in pod walls, as expected from higher starch level and AGPase activity in treated pod walls. The necessity of thermostable AGPase variants in pea to prevent the unfilled-pod problem was discussed.
文摘采用田间小区试验研究“推荐配比”(N:P2O5:K2O比率为190:90:100 kg hm-2)、“高氮量配比”(N:P2O5:K2O比率为210:90:100 kg hm-2)、“低氮量配比”(N:P2O5:K2O比率为170:90:100 kg hm-2)以及“常规配比”(N:P2O5:K2O比率为216:112.5:202.5 kg hm-2)4种氮、磷、钾配比施肥对饲用稻威优198蔗糖合成酶(SUS)、腺苷二磷酸焦磷酸化酶(AGPase)、硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及产量和糙米蛋白质的影响。结果表明:“推荐配比”能提高不同生育时期水稻功能叶(旗叶)和粒籽中碳、氮代谢关键酶的活性,这些关键酶活性的变化显著影响水稻产量和糙米全氮以及蛋白氮的含量。统计(P0.05)结果证实“推荐配比”能提高水稻产量达到8200 kg hm-2,与“常规配比”相比产量提高了24.81%;“推荐配比”糙米全氮和蛋白氮含量分别达到22.70 g kg-1和21.98 g kg-1,与“常规配比”相比差异显著,并且其全氮和蛋白氮含量分别提高17.01%,18.38%。
基金the National Key Research and Development Program of China(GrantNo.G199810100)
文摘The dynamic changes of the activities of enzymes involving in starch biosynthesis, including ADP-glucose pyrophosphorylase (AGPase), soluble starch synthases (SSS), starch branching enzyme (SBE) and starch debranching enzymes (DBE) were studied, and changes of fine structure of amy- lopectin were characterized by isoamylase treatment during rice grain development, using trans anti-waxy gene rice plants. The relationships between the activities of those key enzymes were also analyzed. The amylose synthesis was significantly inhibited in transgenic Wanjing 9522, but the total starch content and final grain weight were less affected as compared with those of non-transgenic Wanjing 9522 rice cultivar. Analyses on the changes of activities of enzymes involving in starch bio- synthesis showed that different enzyme activities were expressed differently during rice endosperm development. Soluble starch synthase is relatively highly expressed in earlier stage of endosperm de- velopment, whilst maximal expression of granule-bound starch synthase (GBSS) occurred in mid-stage of endosperm development. No obvious differences in changes of the activities of AGPase and SBE between two rice cultivars investigated, except the DBEs. Distribution patterns of branches of amy- lopectin changed continually during the development of rice grains and varied between two rice culti- vars. It was suggested that amylopectin synthesis be prior to the synthesis of amylose and different enzymes have different roles in controlling syntheses of branches of amylopectin.
