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，在包括人类在内的真核生物中普遍存在，它们存在于呼吸道、女性生殖道和精子细胞中。据报道，由于缺乏动力蛋白臂而导致的纤毛和鞭毛功能障碍会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马达驱动的，即轴突动力。这项工作的长期目标是了解每一种不同的动力蛋白在纤毛和鞭毛运动中的作用，以及这些动力蛋白的功能如何在纤毛和鞭毛行为的变化中受到调节。我们将尝试通过使用靶向基因敲除技术将种系突变引入编码单细胞原生动物（嗜热四膜虫）1头内臂动力蛋白重链的6个基因中来回答这些问题。该项目的具体目标是：1 .在嗜热四膜虫中产生6个1头内臂动力蛋白重链基因（DYH 8-13）的系系束缚结构域的破坏。2。通过分析各突变株的游泳速度、跳动频率和摄食率，确定各动力蛋白HC在正常纤毛运动中所起的作用。3。验证11和I2/3内臂在Ca++介导的游泳速度降低、纤毛骤停和纤毛搏动逆转中拮抗作用的模型。IV.通过对I2/3突变体进行TEM分析，确定96 nm重复段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内臂动力蛋白的功能和调控的理解

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