Elucidating the molecular mechanisms that shape the hair bundle

描述（由申请人提供）：了解毛细胞的形态发生和运作需要鉴定这些细胞中表达的基因和同源蛋白质的功能。作为实现这一目标的第一步，我们已经使用DNA微阵列技术来识别成年斑马鱼毛细胞中存在的转录本。在从内耳的耳池中分离出纯的毛细胞群体后，我们扩增并标记RNA，并将所得探针与寡核苷酸微阵列杂交。为了排除上皮细胞中普遍表达的基因，我们用肝细胞进行了平行实验，并忽略了它们表达的基因。斑马鱼的毛细胞转录组包括参与囊泡融合、转录调节和跨膜离子运动的基因;其中包括突变时在人类和小鼠中产生耳聋的基因的同源物。其他基因编码的蛋白质参与细胞骨架功能，因此可能有助于形成和维持的毛束。这些成分包括肌动蛋白结合和加帽蛋白以及鞭毛内运输系统的成分。最后，转录谱包括许多功能不确定的基因。利用适用于斑马鱼的分子生物学技术，我们已经开始研究这些基因的产物在发束发育中的作用。毛细胞是内耳和侧线系统的机械感受器，负责听觉、平衡和一些水生脊椎动物对水运动的检测。毛细胞有一毛束，毛束内有机械力传导的装置。为了鉴定毛束的蛋白质成分并深入了解遗传性耳聋，我们正在开发一种斑马鱼功能基因组学方法。

DESCRIPTION (provided by applicant): An understanding of the morphogenesis and operation of hair cells requires identification of the genes expressed in these cells and of the functions of the cognate proteins. As an initial step towards this goal, we have used DNA-microarray technology to identify the transcripts present in hair cells of the adult zebrafish. After isolating pure populations of hair cells from the lagena of the inner ear, we amplified and labeled RNA and hybridized the resultant probes to oligonucleotide microarrays. To exclude genes expressed ubiquitously in epithelial cells, we conducted parallel experiments with hepatocytes and disregarded the genes that they expressed. The hair-cell transcriptome of the zebrafish includes genes involved in vesicle fusion, transcriptional regulation, and transmembrane ion movement; among these are homologs of genes that, when mutated, produce deafness in humans and mice. Additional genes encode proteins that are involved in cytoskeletal function, and might therefore contribute to the formation and maintenance of the hair bundle. These components include actin-binding and -capping proteins as well as constituents of the intraflagellar transport system. Finally, the transcriptional profile encompasses numerous genes of undetermined function. Using the molecular-biological techniques applicable to the zebrafish, we have begun to investigate the roles that some of these genes' products play in hair-bundle development. PUBLIC HEALTH RELEVANCE The hair cell is a mechanoreceptor of the inner ear and lateral-line system that is responsible for hearing, balance, and the detection of water movement by some aquatic vertebrates. The hair cell possesses a hair bundle, which holds the apparatus of mechanotransduction. To identify the protein constituents of the hair bundle and to give insights into hereditary deafness, we are developing a functional genomics approach in zebrafish.