In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on bo...In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on both sides of coleoptiles after seed germination.However,the molecular mechanism of coleoptile purple line is not clear in rice so far.In this study,two major dominant genes,coleoptile purple line 1(OsCPL1,also known as OsC1)and coleoptile purple line 2(OsCPL2),were isolated via map-based cloning,and both of them were required for anthocyanin biosynthesis of coleoptile purple line in rice.The knockout and complementation experiments confirmed that OsC1 was required for purple color in most organs,such as coleoptile line,sheath,auricle,stigma and apiculus,whereas OsCPL2 was just required for coleoptile purple line.OsC1 was predominantly expressed in coleoptiles,flag leaves,and green panicles,and highly expressed in young leaves,whereas OsCPL2 was predominantly expressed in coleoptiles,and extremely lowly expressed in the other tested organs.Loss-of-function of either OsC1 or OsCPL2 resulted in significant reduction of transcript levels of multiple anthocyanin biosynthesis genes in coleoptiles.Coleoptile purple line was further used as a marker trait in hybrid rice.Purity identification in hybrid rice seeds via coleoptile purple line just needed a little water,soil and a small plate and could be completed within 5 d.Molecular marker and field identification analyses indicated that coleoptile purple line was reliable for the hybrid seed purity identification.Our findings disclosed that coleoptile purple line in rice was regulated by two major dominant genes,OsC1 and OsCPL2,and can be used as a simple,rapid,accurate and economic marker trait for seed purity identification in hybrid rice.展开更多
Rice(Oryza sativa)provides>20%of the consumed calories in the human diet.However,rice is also a leading source of dietary cadmium(Cd)that seriously threatens human health.Deciphering the genetic network that underl...Rice(Oryza sativa)provides>20%of the consumed calories in the human diet.However,rice is also a leading source of dietary cadmium(Cd)that seriously threatens human health.Deciphering the genetic network that underlies the grain-Cd accumulation will benefit the development of low-Cd rice and mitigate the effects of Cd accumulation in the rice grain.In this study,we identified a QTL gene,OsCS1,which is allelic to OsMTP11 and encodes a protein sequestering Cd in the leaf during vegetative growth and preventing Cd from being translocated to the grain after heading in rice.OsCS1 is predominantly expressed in leaf vascular parenchyma cells,where it binds to a vacuole-sorting receptor protein OsVSR2 and is translocated intracellularly from the trans-Golgi network to pre-vacuolar compartments and then to the vacuole.In this trafficking process,OsCS1 actively transports Cd into the endomembrane system and sequesters it in the vacuoles.There are natural variations in the promoter of OsCS1 between the indica and japonica rice subspecies.Duplication of a G-box-like motif in the promoter region of the superior allele of OsCS1 from indica rice enhances the binding of the transcription factor OsIRO2 to the OsCS1 promoter,thereby promoting OsCS1 expression.Introgression of this allele into commercial rice varieties could significantly lower grain-Cd levels compared to the inferior allele present in japonica rice.Collectively,our findings offer new insights into the genetic control of leaf-to-grain Cd translocation and provide a novel gene and its superior allele for the genetic improvement of low-Cd variety in rice.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.31701390 and 31370349)Special Project on Performance Incentive Guidance of Chongqing Scientific Research Institution,China(Grant No.cstc2018jxjl80021)+1 种基金Chongqing Agriculture Development Fund(Grant No.NKY-2021AC003)Recruitment Announcement for High-level Talents of Yunnan University(Grant No.KL180018).
文摘In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on both sides of coleoptiles after seed germination.However,the molecular mechanism of coleoptile purple line is not clear in rice so far.In this study,two major dominant genes,coleoptile purple line 1(OsCPL1,also known as OsC1)and coleoptile purple line 2(OsCPL2),were isolated via map-based cloning,and both of them were required for anthocyanin biosynthesis of coleoptile purple line in rice.The knockout and complementation experiments confirmed that OsC1 was required for purple color in most organs,such as coleoptile line,sheath,auricle,stigma and apiculus,whereas OsCPL2 was just required for coleoptile purple line.OsC1 was predominantly expressed in coleoptiles,flag leaves,and green panicles,and highly expressed in young leaves,whereas OsCPL2 was predominantly expressed in coleoptiles,and extremely lowly expressed in the other tested organs.Loss-of-function of either OsC1 or OsCPL2 resulted in significant reduction of transcript levels of multiple anthocyanin biosynthesis genes in coleoptiles.Coleoptile purple line was further used as a marker trait in hybrid rice.Purity identification in hybrid rice seeds via coleoptile purple line just needed a little water,soil and a small plate and could be completed within 5 d.Molecular marker and field identification analyses indicated that coleoptile purple line was reliable for the hybrid seed purity identification.Our findings disclosed that coleoptile purple line in rice was regulated by two major dominant genes,OsC1 and OsCPL2,and can be used as a simple,rapid,accurate and economic marker trait for seed purity identification in hybrid rice.
基金jointly supported by the Strategic Priority Research Program of the CAS(XDA24010404)the National Natural Science Foundation of ChinaNational Natural Science Foundation of China(U19A2026 and 31972490)+1 种基金the Major Program of Natural Science Foundation of Hunan Province(2021JC0007)the Hunan Key Technologies R&D Program Hunan Key Technologies R&D Program(2023NK1010).
文摘Rice(Oryza sativa)provides>20%of the consumed calories in the human diet.However,rice is also a leading source of dietary cadmium(Cd)that seriously threatens human health.Deciphering the genetic network that underlies the grain-Cd accumulation will benefit the development of low-Cd rice and mitigate the effects of Cd accumulation in the rice grain.In this study,we identified a QTL gene,OsCS1,which is allelic to OsMTP11 and encodes a protein sequestering Cd in the leaf during vegetative growth and preventing Cd from being translocated to the grain after heading in rice.OsCS1 is predominantly expressed in leaf vascular parenchyma cells,where it binds to a vacuole-sorting receptor protein OsVSR2 and is translocated intracellularly from the trans-Golgi network to pre-vacuolar compartments and then to the vacuole.In this trafficking process,OsCS1 actively transports Cd into the endomembrane system and sequesters it in the vacuoles.There are natural variations in the promoter of OsCS1 between the indica and japonica rice subspecies.Duplication of a G-box-like motif in the promoter region of the superior allele of OsCS1 from indica rice enhances the binding of the transcription factor OsIRO2 to the OsCS1 promoter,thereby promoting OsCS1 expression.Introgression of this allele into commercial rice varieties could significantly lower grain-Cd levels compared to the inferior allele present in japonica rice.Collectively,our findings offer new insights into the genetic control of leaf-to-grain Cd translocation and provide a novel gene and its superior allele for the genetic improvement of low-Cd variety in rice.
