Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of ce...Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of cell death regulation in LMMs needs further study. In this study, we identified a rice light-dependent leaf lesion mimic mutant 4(llm4) that showed abnormal chloroplast structure, photoinhibition, reduced photosynthetic protein levels, massive accumulation of reactive oxygen species(ROS), and PCD. Map-based cloning and complementation testing revealed that LLM4 encodes zeaxanthin epoxidase(ZEP), an enzyme involved in the xanthophyll cycle, which functions in plant photoprotection,ROS scavenging, and carotenoid and abscisic acid(ABA) biosynthesis. The ABA content was decreased,and the contents of 24 carotenoids differed between the llm4 mutant and the wild type(WT). The llm4mutant showed reduced dormancy and greater sensitive to ABA than the WT. We concluded that the mutation of LLM4 resulted in the failure of xanthophyll cycle, in turn causing ROS accumulation. The excessive ROS accumulation damaged chloroplast structure and induced PCD, leading eventually to the formation of lesion mimics.展开更多
At present,there is a problem of false positives caused by the too vast mimic scope in mimic transformation technology.Previous studies have focused on the“compensation”method to deal with this problem,which is expe...At present,there is a problem of false positives caused by the too vast mimic scope in mimic transformation technology.Previous studies have focused on the“compensation”method to deal with this problem,which is expensive and cannot fundamentally solve it.This paper provides new insights into coping with the situation.Firstly,this study summarizes the false-positive problem in the mimic transformation,analyzes its possible harm and the root causes.Secondly,three properties about the mimic scope are proposed.Based on the three properties and security quantification technology,the best mimic component set theory is put forward to solve the false-positive problem.There are two algorithms,the supplemental method and the subtraction method.The best mimic component set obtained by these two algorithms can fundamentally solve the mimic system’s false-positive problem but reduce the cost of mimic transformation.Thus make up for the lack of previous researches.展开更多
介绍了Mimics(Materiaise's interactive medical image control system)软件及医学图像三维重建的方法,并对该软件在医学图像三维重建中的应用现状进行了分析。指出Mimics软件是连接二维断层扫描图像和三维图像的桥梁,其更重视实...介绍了Mimics(Materiaise's interactive medical image control system)软件及医学图像三维重建的方法,并对该软件在医学图像三维重建中的应用现状进行了分析。指出Mimics软件是连接二维断层扫描图像和三维图像的桥梁,其更重视实现可视化之后的后续研究,并且可以实现个人普通计算机上大规模数据的转换处理,无需专业工作站,将二维扫描的数据(CT、MRI)输入该软件可快速生成三维模型并进行编辑,为医生日常临床诊疗以及科研工作使用提供帮助。最后对其应用前景进行了展望。展开更多
基金the financial support of the National Natural Science Foundation of China (32060454, 32272109)Hainan Yazhou Bay Seed Laboratory (B21HJ0215)+1 种基金National Natural Science Foundation of China (32072048, U2004204)Specific Research Fund of The Innovation Platform for Academicians of Hainan Province。
文摘Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of cell death regulation in LMMs needs further study. In this study, we identified a rice light-dependent leaf lesion mimic mutant 4(llm4) that showed abnormal chloroplast structure, photoinhibition, reduced photosynthetic protein levels, massive accumulation of reactive oxygen species(ROS), and PCD. Map-based cloning and complementation testing revealed that LLM4 encodes zeaxanthin epoxidase(ZEP), an enzyme involved in the xanthophyll cycle, which functions in plant photoprotection,ROS scavenging, and carotenoid and abscisic acid(ABA) biosynthesis. The ABA content was decreased,and the contents of 24 carotenoids differed between the llm4 mutant and the wild type(WT). The llm4mutant showed reduced dormancy and greater sensitive to ABA than the WT. We concluded that the mutation of LLM4 resulted in the failure of xanthophyll cycle, in turn causing ROS accumulation. The excessive ROS accumulation damaged chloroplast structure and induced PCD, leading eventually to the formation of lesion mimics.
基金This work was supported by National Key Research and Development Program of China(Grant No.2018YF0804001).
文摘At present,there is a problem of false positives caused by the too vast mimic scope in mimic transformation technology.Previous studies have focused on the“compensation”method to deal with this problem,which is expensive and cannot fundamentally solve it.This paper provides new insights into coping with the situation.Firstly,this study summarizes the false-positive problem in the mimic transformation,analyzes its possible harm and the root causes.Secondly,three properties about the mimic scope are proposed.Based on the three properties and security quantification technology,the best mimic component set theory is put forward to solve the false-positive problem.There are two algorithms,the supplemental method and the subtraction method.The best mimic component set obtained by these two algorithms can fundamentally solve the mimic system’s false-positive problem but reduce the cost of mimic transformation.Thus make up for the lack of previous researches.
文摘介绍了Mimics(Materiaise's interactive medical image control system)软件及医学图像三维重建的方法,并对该软件在医学图像三维重建中的应用现状进行了分析。指出Mimics软件是连接二维断层扫描图像和三维图像的桥梁,其更重视实现可视化之后的后续研究,并且可以实现个人普通计算机上大规模数据的转换处理,无需专业工作站,将二维扫描的数据(CT、MRI)输入该软件可快速生成三维模型并进行编辑,为医生日常临床诊疗以及科研工作使用提供帮助。最后对其应用前景进行了展望。
