Chloroplasts are essential for plant growth and development,as they play a key role in photosynthesis.The chloroplast biogenesis process is complex and its regulatory mechanism remains elusive.We characterized a spont...Chloroplasts are essential for plant growth and development,as they play a key role in photosynthesis.The chloroplast biogenesis process is complex and its regulatory mechanism remains elusive.We characterized a spontaneous Brassica napus(rapeseed)mutant,ytg,that showed a delayed greening phenotype in all green organs and retarded growth.We identified Bna A02.YTG1 encoding a chloroplastlocalized tetratricopeptide repeat protein widely expressed in rapeseed tissues.We speculated that the ytg phenotype was caused by the deletion of Bna A02.YTG1 based on sequence comparison of 4608(with normal green leaves,isolated from the elite Chinese rapeseed cultivar ZS11)and ytg combined with transcriptome data and CRISPR/Cas9 gene editing results.The homologous gene(Bna C02.YTG1)restored the phenotype of the mutant.Bna A02.YTG1 interacted with MORF2,MORF8,and OZ1.RNA editing of the ndh D-2,ndh F-290,pet L-5,and ndh G-50 plastid transcripts was affected in ytg.These findings suggested that Bna A02.YTG1 participates in RNA editing events.We predicted 29 RNA editing sites in the chloroplast of Brassica napus by comparison with the Arabidopsis chloroplast genome.We conclude that Bna A02.YTG1 affects the posttranscriptional regulation of plastid gene expression and suggest that a tetratricopeptide repeat protein is involved in the chloroplast RNA editing in rapeseed.展开更多
Fast and accurate prediction of urban flood is of considerable practical importance to mitigate the effects of frequent flood disasters in advance.To improve urban flood prediction efficiency and accuracy,we proposed ...Fast and accurate prediction of urban flood is of considerable practical importance to mitigate the effects of frequent flood disasters in advance.To improve urban flood prediction efficiency and accuracy,we proposed a framework for fast mapping of urban flood:a coupled model based on physical mechanisms was first constructed,a rainfall-inundation database was generated,and a hybrid flood mapping model was finally proposed using the multi-objective random forest(MORF)method.The results show that the coupled model had good reliability in modelling urban flood,and 48 rainfall-inundation scenarios were then specified.The proposed hybrid MORF model in the framework also demonstrated good performance in predicting inundated depth under the observed and scenario rainfall events.The spatial inundated depths predicted by the MORF model were close to those of the coupled model,with differences typically less than 0.1 m and an average correlation coefficient reaching 0.951.The MORF model,however,achieved a computational speed of 200 times faster than the coupled model.The overall prediction performance of the MORF model was also better than that of the k-nearest neighbor model.Our research provides a novel approach to rapid urban flood mapping and flood early warning.展开更多
基金the National Key Research and Development Program of China(2016YFD0100305)。
文摘Chloroplasts are essential for plant growth and development,as they play a key role in photosynthesis.The chloroplast biogenesis process is complex and its regulatory mechanism remains elusive.We characterized a spontaneous Brassica napus(rapeseed)mutant,ytg,that showed a delayed greening phenotype in all green organs and retarded growth.We identified Bna A02.YTG1 encoding a chloroplastlocalized tetratricopeptide repeat protein widely expressed in rapeseed tissues.We speculated that the ytg phenotype was caused by the deletion of Bna A02.YTG1 based on sequence comparison of 4608(with normal green leaves,isolated from the elite Chinese rapeseed cultivar ZS11)and ytg combined with transcriptome data and CRISPR/Cas9 gene editing results.The homologous gene(Bna C02.YTG1)restored the phenotype of the mutant.Bna A02.YTG1 interacted with MORF2,MORF8,and OZ1.RNA editing of the ndh D-2,ndh F-290,pet L-5,and ndh G-50 plastid transcripts was affected in ytg.These findings suggested that Bna A02.YTG1 participates in RNA editing events.We predicted 29 RNA editing sites in the chloroplast of Brassica napus by comparison with the Arabidopsis chloroplast genome.We conclude that Bna A02.YTG1 affects the posttranscriptional regulation of plastid gene expression and suggest that a tetratricopeptide repeat protein is involved in the chloroplast RNA editing in rapeseed.
基金financial or data support of the National Key R&D Program of China(2021YFC3001000)the National Natural Science Foundation of China(U1911204,51879107)+1 种基金the Natural Science Foundation of Guangdong Province(2023B1515020087,2022A1515010019)the Fund of Science and Technology Program of Guangzhou(202102020216)。
文摘Fast and accurate prediction of urban flood is of considerable practical importance to mitigate the effects of frequent flood disasters in advance.To improve urban flood prediction efficiency and accuracy,we proposed a framework for fast mapping of urban flood:a coupled model based on physical mechanisms was first constructed,a rainfall-inundation database was generated,and a hybrid flood mapping model was finally proposed using the multi-objective random forest(MORF)method.The results show that the coupled model had good reliability in modelling urban flood,and 48 rainfall-inundation scenarios were then specified.The proposed hybrid MORF model in the framework also demonstrated good performance in predicting inundated depth under the observed and scenario rainfall events.The spatial inundated depths predicted by the MORF model were close to those of the coupled model,with differences typically less than 0.1 m and an average correlation coefficient reaching 0.951.The MORF model,however,achieved a computational speed of 200 times faster than the coupled model.The overall prediction performance of the MORF model was also better than that of the k-nearest neighbor model.Our research provides a novel approach to rapid urban flood mapping and flood early warning.
