Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to ...Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent 93-11.Further investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive effect.LOC_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of qGW11a.Overexpression of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain weight.The 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and weight.These results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice.展开更多
Calcium-dependent protein kinases(CPKs),the best-characterized calcium sensors in plants,regulate many aspects of plant growth and development as well as plant adaptation to biotic and abiotic stresses.However,how CPK...Calcium-dependent protein kinases(CPKs),the best-characterized calcium sensors in plants,regulate many aspects of plant growth and development as well as plant adaptation to biotic and abiotic stresses.However,how CPKs regulate the antioxidant defense system remains largely unknown.We previously found that impaired function of OsCPK12 leads to oxidative stress in rice,with more H_(2)O_(2),lower catalase(CAT)activity,and lower yield.Here,we explored the roles of OsCPK12 in oxidative stress tolerance in rice.Our results show that OsCPK12 interacts with and phosphorylates OsCATA and OsCATC at Ser11.Knockout of either OsCATA or OsCATC leads to an oxidative stress phenotype accompanied by higher accumulation of H_(2)O_(2).Overexpression of the phosphomimetic proteins OsCATAS11D and OsCATCS11D in oscpk12-cr reduced the level of H2O2 accumulation.Moreover,OsCATAS11D and OsCATCS11D showed enhanced catalase activity in vivo and in vitro.OsCPK12-overexpressing plants exhibited higher CAT activity as well as higher tolerance to oxidative stress.Ourndings demonstrate that OsCPK12 affects CAT enzyme activity by phosphorylating OsCATA and OsCATC at Ser11 to regulate H2O2 homeostasis,thereby mediating oxidative stress tolerance in rice.展开更多
基金supported by grants from the National Natural Science Foundation of China(32325038)the Postdoctoral Fellowship Program of CPSF(GZB20230499)+1 种基金the Sichuan Science and Technology Program(24NSFSC4494)the Open Project Program(SKL-ZY202212)of State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China.We thank the High-Performance Computing Platform of Sichuan Agricultural University for its support for the analysis of substitution segments in CSSL9-17.
文摘Grain size is a key factor influencing grain weight in rice.In this study,a chromosome segment substitution line(CSSL9-17)was identified,that exhibits a significant reduction in both grain size and weight compared to its donor parent 93-11.Further investigation identified two quantitative trait loci(QTL)on chromosome 11,designated qGW11a and qGW11b,which contribute to 1000-grain weight with an additive effect.LOC_Os11g05690,encoding the amino acid permease OsCAT8,is the target gene of qGW11a.Overexpression of OsCAT8 resulted in decreased grain weight,while OsCAT8 knockout mutants exhibited increased grain weight.The 287-bp located within the OsCAT8 promoter region of 93-11 negatively regulates its activity,which is subsequently correlated with an increase in grain size and weight.These results suggest that OsCAT8 functions as a negative regulator of grain size and grain weight in rice.
基金supported by grants from the National Natural Science Foundation of China (#32100224 and#31961143016)the Science and Technology Program of Zhejiang Province,China (2022R51009)+2 种基金the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences (CAAS-ASTIP-2013-CNRRI)the Earmarked Fund for the China Agricultural Research System (CARS-01)the Zhejiang Provincial Natural Science Foundation of China (grant no.LY23C130003).No conflict of interest is declared.
文摘Calcium-dependent protein kinases(CPKs),the best-characterized calcium sensors in plants,regulate many aspects of plant growth and development as well as plant adaptation to biotic and abiotic stresses.However,how CPKs regulate the antioxidant defense system remains largely unknown.We previously found that impaired function of OsCPK12 leads to oxidative stress in rice,with more H_(2)O_(2),lower catalase(CAT)activity,and lower yield.Here,we explored the roles of OsCPK12 in oxidative stress tolerance in rice.Our results show that OsCPK12 interacts with and phosphorylates OsCATA and OsCATC at Ser11.Knockout of either OsCATA or OsCATC leads to an oxidative stress phenotype accompanied by higher accumulation of H_(2)O_(2).Overexpression of the phosphomimetic proteins OsCATAS11D and OsCATCS11D in oscpk12-cr reduced the level of H2O2 accumulation.Moreover,OsCATAS11D and OsCATCS11D showed enhanced catalase activity in vivo and in vitro.OsCPK12-overexpressing plants exhibited higher CAT activity as well as higher tolerance to oxidative stress.Ourndings demonstrate that OsCPK12 affects CAT enzyme activity by phosphorylating OsCATA and OsCATC at Ser11 to regulate H2O2 homeostasis,thereby mediating oxidative stress tolerance in rice.
