REGULATION OF ASYMMETRIC FLAGELLAR WAVEFORMS

单细胞绿藻衣藻可以与两种截然不同的 鞭毛波形。前向游泳是使用一个 不对称的节拍，类似于纤毛的节拍。反向游泳是 由对称的波形完成，类似于经典的鞭毛 打人。这两个窗体之间的转换由 轴丝周围的钙离子收缩。两类不同的突变体 在衣藻中已经被分离出来，它们已经失去了 产生不对称波形：中央配对装置有缺陷 变种人，只向后移动变种人。的最新发展 这种有机体中的插入突变使其有可能迅速 在多个调节鞭毛功能的基因中产生突变并进行克隆 受影响的基因。这项技术将在这个项目开始时使用 黄曲霉毒素的分子、生化和超微结构分析 鞭毛波形的调节。具体目标是：1)使用 插入诱变法鉴定和克隆其产物为 衣藻产生不对称波形所必需的 2)鉴定cad和mbo基因的基因产物。 测序基因组和cdna克隆；3)对每个基因产物进行定位 在鞭毛内；4)通过以下方式解决每个基因产物的功能 突变表型的详细特征。衣藻是 可用于鞭毛结构研究的初级遗传系统和 功能。数十个影响鞭毛功能的突变体已经被很好地- 特征，以及许多编码成分的基因 微管、径向辐条组件和动力蛋白臂已被分离。 中央器官可能是人类最不了解的区域 轴丝。该产品将识别和表征许多 参与不对称鞭毛波形产生的蛋白质。 这项研究将在几个方面促进我们对人类生物学的理解 重要途径，鉴于纤毛在呼吸功能中的重要作用 以及鞭毛在男性生育中的作用。

The unicellular green alga Chlamydomonas can swim with two very different flagellar waveforms. Forward swimming is accomplished using an asymmetric beat, resembling the beat of cilia. Reverse swimming is accomplished by a symmetrical waveform, similar to classic flagellar beating. The transition between the two forms is controlled by the contraction of Ca++ around the axoneme. Two different classes of mutants in Chlamydomonas have been isolated which have lost the ability to generate the asymmetric waveform: central pair apparatus defective mutants and move backward only mutants. The recent development of insertional mutagenesis in this organism has made it possible to rapidly generate mutants in many genes regulating flagellar function and to clone the affected genes. This technique will be used in this project to begin a comprehensive molecular, biochemical and ultrastructural analysis of the regulation of flagellar waveforms. The specific aims are: 1) to use insertional mutagenesis to identify and clone genes whose products are required for generation of an asymmetric waveform in Chlamydomonas flagella; 2) to identify the gene products of each cad and mbo gene by sequencing genomic and cDNA clones; 3) to localize each gene product within the flagellum; 4) to address the function of each gene product by detailed characterization of mutant phenotypes. Chlamydomonas is the primary genetic system available for the study of flagellar structure and function. Dozens of mutants affecting flagellar function have been well- characterized, and many of the genes coding for components of the microtubules, radial spoke assembly and dynein arms have been isolated. The central apparatus is perhaps the least understood region of the axoneme. This product will identify and characterize many of the proteins involved in the generation of the asymmetric flagellar waveform. This research will advance our understanding of human biology in several important ways, given the important role of cilia in respiratory function and the role of flagella in male fertility.