GENETIC ANALYSIS OF CELL-CELL SIGNALING IN MYXOCOCCUS

这项研究将描述原核生物中的细胞通讯 黄色粘球菌，发育过程中多细胞行为的模型。 重点将是促进细胞间相互作用的分子和细胞- 细胞信号。对这一模型的研究将在生物学上阐明 触发细胞分化的因素，刺激细胞的因素 增殖，以及引导细胞迁移和附着的因素。基本信息 研究可能提供促进红血球分化的因素 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。 基于基因转座子标签的遗传方法提供了一种新的 发现细胞表面通讯因子的技术 单元格之间的消息。利用转座子标记Will进行遗传分析 精确定位控制细胞运动的特定细胞表面因子，称为 “接触滑行”因素。这些因素似乎在监管中 在发育过程中，自然和引导形态发生运动。突变 影响接触滑动生物合成的因子将被分离并 利用遗传互补和遗传作图将基因分组为基因 技巧。这些基因将被克隆和测序，以便 描述这些因素的分子性质。的刺激 通过这些因素的细胞运动将创造一种生物测定来纯化这些 细胞间信号转导中的影响因素和活性特征。 细胞表面的脂多糖(LPS)可能是靶标或 接触性滑动因子受体在运动调节机制中的作用。 在内毒素或接触滑动因子方面有缺陷的突变体将被检查 运动异常和异常的多细胞行为。突变型 定向细胞运动和协同细胞运动的异常 在多细胞发育过程中将使用延时分析 视频显微镜和扫描电子显微镜。抗肿瘤的单抗 细胞表面脂多糖的MAP电位变化 形态发生运动。内毒素的化学分析将显示正常 脂多糖的结构，并显示在特定突变体中缺失的糖 内毒素有缺陷。这项分析将揭示脂多糖中的特定糖类 细胞之间的分子接触所必需的，或细胞和 细胞间信号，在引导形态发生运动中起重要作用 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.