REGULATION OF DEVELOPMENT IN CAULOBACTER CRESCENTUS

Crescentus是一种革兰氏阴性微生物，它不均匀地分裂产生 一个不活动的有柄细胞和一个较小的有鞭毛的沼泽细胞，每个细胞都有 不同的发育顺序。这种有机体是一种理想的模型系统 干细胞分化的研究。中开发的两个相关方面 C.crescentus是值得关注的物种。(1)时间模式--程序如何 在一个细胞中编码的一系列有序的结构和功能变化？和 (2)空间模式--结构和功能信息如何本地化 在某种程度上会导致细胞分裂不平等？我们的主要方法是 研究控制这一时间方面的分子机制 控件如下所示。 答：正在使用遗传分析来确定哪些细胞周期事件是 负责调节硫杆菌周期蛋白的合成。 具体地说，鞭毛蛋白的诱导和关闭 和钩蛋白，正在条件细胞周期突变体和在 以某种方式解除管制以表达这些基因之一的突变体 蛋白质。B.检查鞭毛或其他发育阶段的表达 蛋白质连接到细胞周期，我们计划通过以下方式分离受调控的基因 分子克隆以研究它们的结构和在植物中的表达 体外培养。这种分析的一个初步阶段是分离和鉴定。 卡氏杆菌的核糖体基因。

C. Crescentus is a gram-negative microorganism that divides unequally to produce a non-motile stalked cell and a smaller, flagellated swarmer cell, each with different developmental sequences. This organism is an ideal model system for the study of stem cell differentiation. Two related aspects of development in C. crescentus are of interest. (1) Temporal patterns - How is the program for an ordered series of structural and functional changes encoded in a cell? and (2) Spatial patterns - How is structure and functional information localized within a cell in a way to lead to unequal cell division? Our main approaches to studying the molecular mechanisms that control the temporal aspects of this control are the following. A. A genetic analysis is being used to determine which cell cycle events are responsible for regulation of periodic protein synthesis in Caulobacter. Specifically, the induction and shut off of the flagellar proteins, flagellin and hook protein, are being examined in conditional cell cycle mutants and in mutants which are deregulated in some way for expression of one of these proteins. B. To examine how expression of flagellar or other developmental proteins are coupled to the cell cycle we plan to isolate the regulated genes by molecular cloning in order to study their structure and their expression in vitro. A preliminary stage in this analysis is isolation and characterization of the ribosomal genes from Caulobacter.