The genetic pathways of rice seedling growth have a major impact on seedling emergence from soil and development.In this study,we identified a new bHLH transcription factor,BEAR1,from rice RNAi mutant library.Both the...The genetic pathways of rice seedling growth have a major impact on seedling emergence from soil and development.In this study,we identified a new bHLH transcription factor,BEAR1,from rice RNAi mutant library.Both the BEAR1-RNAi and bear1 CRISPR mutants had accelerated seedling growth.Histological section of leaves showed accelerated development of lacuna and vascular bundles in bear1 mutant.GUS staining revealed that BEAR1 was highly expressed in coleoptiles and leaves at seedling stage.Expression analysis of gibberellin(GA)biosynthesis and metabolic genes and content determination of active GAs indicated that the expression of GA biosynthesis genes,especially OsKS4 and OsCPS2,were upregulated and the GAs content were significantly increased in bear1,which correlated with the seedling phenotype of bear1 mutant.Molecular and biochemical assays revealed that BEAR1 directly binds to the promoter of OsKS4,thereby repressing its expression.Haplotypes analysis showed clear differentiation in indica and japonica rice varieties,and a strong correlation with seedling height.These findings provide novel insights into the regulation of seedling growth in rice.展开更多
Submergence is a serious environmental condition that causes large loss in rice production in rain fed lowland and flood affected area. This study evaluated morphological and physiological responses of rice roots to s...Submergence is a serious environmental condition that causes large loss in rice production in rain fed lowland and flood affected area. This study evaluated morphological and physiological responses of rice roots to submergence using two tolerant rice genotypes FR13A and Swarna-Sub 1 and two sensitive ones Swarna and IR42. The tolerant genotypes had higher survival rate and less shoot elongation but greater root elongation during submergence than the sensitive ones. After submergence,the tolerant genotypes also had higher root dry weight and more active roots than the sensitive ones.Tolerant genotypes exhibited less root injury, with less malondialdehyde production and slower electrolyte leakage after submergence. Tolerant genotypes also maintained higher concentrations of soluble sugar and starch in roots and shoots and higher chlorophyll retention after submergence than the sensitive ones.Our data showed that root traits such as root activity and root growth are associated with survival rate after submergence. This is probably accomplished through higher energy supply, and membrane integrity is necessary to preserve root function and reduce injury during submergence. These root traits are important for submergence tolerance in rice.展开更多
Dear editor,I am Dr.Jie Peng,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of a novel in-frame del...Dear editor,I am Dr.Jie Peng,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of a novel in-frame deletion mutation c.17779del TAC of neurofibromatosis type 1 in a Chinese boy with bilateral blindness.Neurofibromatosis type 1(NF1;OMIM#162200),an autosomal dominant disease,is caused by mutations in the NF1gene.The incidence of this disease is around 1 in 3500展开更多
基金supported by the National Natural Science Foundation of China(32071932)Scientific Research Foundation for Scholars of HZNU(2019QDL015)the Natural Science Foundation of Zhejiang province(LQ22C130001)。
文摘The genetic pathways of rice seedling growth have a major impact on seedling emergence from soil and development.In this study,we identified a new bHLH transcription factor,BEAR1,from rice RNAi mutant library.Both the BEAR1-RNAi and bear1 CRISPR mutants had accelerated seedling growth.Histological section of leaves showed accelerated development of lacuna and vascular bundles in bear1 mutant.GUS staining revealed that BEAR1 was highly expressed in coleoptiles and leaves at seedling stage.Expression analysis of gibberellin(GA)biosynthesis and metabolic genes and content determination of active GAs indicated that the expression of GA biosynthesis genes,especially OsKS4 and OsCPS2,were upregulated and the GAs content were significantly increased in bear1,which correlated with the seedling phenotype of bear1 mutant.Molecular and biochemical assays revealed that BEAR1 directly binds to the promoter of OsKS4,thereby repressing its expression.Haplotypes analysis showed clear differentiation in indica and japonica rice varieties,and a strong correlation with seedling height.These findings provide novel insights into the regulation of seedling growth in rice.
基金supported by German Federal Ministry from Economic Cooperation and Development (BMZ)
文摘Submergence is a serious environmental condition that causes large loss in rice production in rain fed lowland and flood affected area. This study evaluated morphological and physiological responses of rice roots to submergence using two tolerant rice genotypes FR13A and Swarna-Sub 1 and two sensitive ones Swarna and IR42. The tolerant genotypes had higher survival rate and less shoot elongation but greater root elongation during submergence than the sensitive ones. After submergence,the tolerant genotypes also had higher root dry weight and more active roots than the sensitive ones.Tolerant genotypes exhibited less root injury, with less malondialdehyde production and slower electrolyte leakage after submergence. Tolerant genotypes also maintained higher concentrations of soluble sugar and starch in roots and shoots and higher chlorophyll retention after submergence than the sensitive ones.Our data showed that root traits such as root activity and root growth are associated with survival rate after submergence. This is probably accomplished through higher energy supply, and membrane integrity is necessary to preserve root function and reduce injury during submergence. These root traits are important for submergence tolerance in rice.
文摘Dear editor,I am Dr.Jie Peng,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of a novel in-frame deletion mutation c.17779del TAC of neurofibromatosis type 1 in a Chinese boy with bilateral blindness.Neurofibromatosis type 1(NF1;OMIM#162200),an autosomal dominant disease,is caused by mutations in the NF1gene.The incidence of this disease is around 1 in 3500
