Function and Regulation of Inner Arm Dyneins

描述（由申请人提供）：纤毛和鞭毛是复杂的微管细胞器，在真核生物（包括人类）中普遍存在，它们存在于呼吸道、雌性生殖道和精子细胞中。由于动力蛋白臂的缺失而导致的纤毛和鞭毛功能障碍已被报道导致人类和其他哺乳动物的呼吸和生育问题。纤毛和鞭毛的运动是由一组复杂的分子发动机驱动的，轴丝动力蛋白。这项工作的长期目标是了解每种不同的动力蛋白在纤毛和鞭毛运动中的作用，以及在纤毛和鞭毛行为变化过程中这些动力蛋白的功能是如何调节的。我们将试图回答这些问题，通过使用有针对性的基因敲除技术引入生殖系突变到6个基因编码的1头内臂动力蛋白重链的单细胞原生动物，嗜热四膜虫。该项目的具体目标是：在嗜热四膜虫的6个1-头内臂动力蛋白重链基因（DYH 8-13）中产生系留结构域的种系破坏。二.通过分析每个突变株的游泳速度、节拍频率和进食率，确定每个动力蛋白HC在正常纤毛运动中所起的作用。三.测试I1和I2/3内臂在Ca++介导的游泳速度降低、纤毛停止和纤毛搏动逆转期间拮抗作用的模型。四.通过对I2/3突变体进行TEM分析，确定96 nm重复序列中内臂动力蛋白的组织。这项工作的结果应该增加我们对纤毛和鞭毛中内臂动力蛋白的功能和调节的理解

DESCRIPTION (provided by applicant): Cilia and flagella are complex microtubular organelles that are ubiquitous among eukaryotes, including humans, where they are found in the respiratory tract, the female reproductive tract and on sperm cells. Ciliary and flagellar dysfunction resulting from the absence of dynein arms has been reported to cause respiratory and fertility problems in humans and other mammals. Movement of cilia and flagella is driven by a complex group of molecular motors, the axonemal dyneins. The long-term objectives of this work are to understand the role(s) each different dynein play in ciliary and flagellar motility and how the functions of those dyneins are regulated during changes in ciliary and flagellar behavior. We will attempt to answer those questions by using targeted gene knockout techniques to introduce germ-line mutations into six genes encoding the 1-headed inner arm dynein heavy chains in the unicellular protozoan, Tetrahymena thermophila. The specific aims of this project are: I. Generate germ line disruptions of the tethering domain in six 1-headed inner arm dynein heavy chain genes (DYH 8-13) in Tetrahymena thermophila. II. Determine the role each dynein HC plays in normal ciliary movement by analyzing swimming speed, beat frequency, and feeding rate of each mutant strain. III. Test the model that the 11 and I2/3 inner arms act antagonistically during Ca++-mediated decreased swimming speed, ciliary arrest, and reversal of ciliary beat. IV. Determine the organization of inner arm dyneins in the 96 nm repeat by performing TEM analyses of I2/3 mutants. The results of this work should add to our understanding of the function and regulation of the inner arm dyneins in cilia and flagella