GENETIC ANALYSIS OF CELL-CELL SIGNALING IN MYXOCOCCUS

这项研究将描述原核细胞中的细胞通讯 黄色粘球菌：发育过程中多细胞行为的模型。 重点将是促进细胞-细胞相互作用和细胞- 细胞信号 对这一模型的研究将在生物学上揭示 触发细胞分化的因子 增殖以及引导细胞迁移和附着的因子。 基本 研究可以提供促进红细胞分化的因素 细胞、促进伤口愈合的发育因子和癌基因产物 控制肿瘤细胞的行为。 一种基于转座子标记基因的遗传学方法提供了一种新的 一种发现细胞表面因子的技术， 细胞之间的信息。 使用转座子标记的遗传分析将 精确定位控制细胞运动的特定细胞表面因子，称为 “接触滑移”因素。 这些因素似乎是调节， 在发育过程中引导形态发生运动。 突变 将分离影响接触滑动因子生物合成的细胞， 利用遗传互补和遗传作图将其分为基因组 技术. 这些基因将被克隆和测序， 描述这些因素的分子性质。 的刺激 通过这些因子的细胞运动将产生用于纯化这些细胞的生物测定。 因子并表征它们在细胞间信号传导中的活性。 细胞表面的脂多糖（LPS）可能是靶点， 接触滑动因子受体在调节运动机制中的作用。 将检查LPS或接触滑动因子缺陷的突变体 异常的运动和异常的多细胞行为。 突变体 定向细胞运动和协同细胞运动异常 在多细胞发育过程中，将使用时间推移分析 视频显微镜和扫描电子显微镜。 单克隆抗体 绘制细胞表面脂多糖的潜在变化， 形态发生运动 脂多糖的化学分析显示 LPS的结构，并显示在特定突变体中缺失的糖 LPS缺陷。 该分析将揭示LPS中的特定糖 细胞之间或细胞与细胞之间的分子接触所必需的， 细胞间信号，在指导形态发生运动过程中的重要作用 发展

The research will characterize cell communication in the procaryote Myxococcus xanthus, a model for multicellular behavior during development. The focus will be molecules which promote cell-cell interactions and cell- cell signaling. Research in this model will shed light in biology on factors triggering cell differentiation, factors stimulating cell proliferation, and factors guiding cell migration and attachment. Basic research could provide factors promoting differentiation in red blood cells, development factors promoting wound healing, and oncogene products controlling tumor cell behavior. A genetic approach based on the transposon tagging of genes provides a new technique for discovering factors on the cell surface which communicate messages between cells. Genetic analysis using transposon tagging will pinpoint specific cell-surface factors controlling cell motility, called "contact gliding" factors. These factors appear to be regulatory in nature and guide morphogenetic movements during development. Mutations affecting the biosynthesis of contact gliding factors will be isolated and grouped into genes using genetic complementation and genetic mapping techniques. The genes will be cloned and sequenced in order to characterize the molecular nature of these factors. The stimulation of cell motility by these factors will create a bioassay for purifying these factors and characterizing their activity in intercellular signaling. Lipopolysaccharide (LPS) on the cell surface might be the target or receptor for contact gliding factors in regulating motility mechanism. Mutants defective in either LPS or contact gliding factors will be examined for abnormal motility and aberrant multicellular behavior. Mutant abnormalities in directed cell movement and cooperative cell movement during multicellular development will be analyzed using time-lapsed videomicroscopy and scanning electron microscopy. Monoclonal antibody to map potential change in lipopolysaccharide on the cell surface during morphogenetic movements. Chemical analysis of LPS will show the normal structure of LPS and show the sugars missing in particular mutants defective in LPS. This analysis will reveal the specific sugars in LPS required for molecular contacts between cells, or between cells and intercellular signals, important in guiding morphogenetic movements during development.