Messenger RNA Processing in Chloroplasts

本研究的目的是研究叶绿体mRNA的加工，重点是mRNA的剪接，以提高我们对叶绿体生物发生和功能的理解。先前的结果对菠菜叶绿体中编码9个叶绿体ATP合成酶亚基中的4个的基因簇的加工和剪接提出了有趣的问题。初步数据表明，叶绿体mRNA剪接可能导致同一内含子内出现多个分支点。这项建议的三个目标之一是调查这些初步结果。PI检测了菠菜叶绿体提取物的剪接活性。本提案的两个目标是致力于这种体外剪接活性的稳定和初步表征研究。目前尚不清楚剪接是否是控制基因表达的一个限速步骤，但它是产生一些必需基因产物的必不可少的步骤。在这个提议中，计划是研究叶绿体剪接在体内和体外，以开始了解这个复杂的过程和调节它的因素。叶绿体基因的表达受光、热胁迫和生理等多种因素的调控。这项工作将有助于阐明调控叶绿体发生和功能的控制点

The purpose of this proposal is to study chloroplast mRNA processing, with an emphasis on mRNA splicing, as a way to enhance our understanding of chloroplast biogenesis and function. Previous results have posed intriguing questions about the processing and splicing of a gene cluster in spinach chloroplasts that encodes four of the nine chloroplast ATP synthase subunits. Preliminary data suggests that chloroplast mRNA splicing may result in multiple branch points within the same intron. One of the three objectives of this proposal is to investigate those preliminary results. The PI has detected splicing activity in spinach chloroplast extracts. Tow objectives of this proposal are dedicated to the stabilization and initial characterization studies on this in vitro splicing activity. It is not known whether splicing is a rate limiting step in the control of gene expression, but it is an indispensable step in the production of several essential gene products. In this proposal, the plan is to study chloroplast splicing both in vivo and in vitro in order to begin to understand this complex process and the factors that regulate it. Chloroplast gene expression is regulated by several factors including light, heat stress, and physiological factors. This work will help to elucidate control points that regulate chloroplast biogenesis and function.//