Unconventional Myosin - Organelle Interactions

小鼠“稀疏”非传统肌球蛋白(Myo5a)基因座为研究非传统肌球蛋白家族密切相关成员的分子马达-货物相互作用和重叠功能提供了一个出色的遗传系统。“稀疏”系统的几个方面有助于提供回答这些问题的有效方法：在“稀疏”基因座和“灰白”、“铅”和“稀疏抑制者”基因座有多个突变等位基因的可用性；美世公司最近对“稀疏”家族的第二个哺乳动物成员MYR 6(Myo5b)的特征；操纵小鼠基因组的能力；以及提供“稀疏”肌球蛋白功能可视化分析的原代黑素细胞培养系统的可用性。这些研究将通过深入了解运动-货物相互作用和测试非传统肌球蛋白家族中的功能冗余来影响细胞器运输领域。研究有以下目标：1，利用细胞生物学、生物化学和遗传学方法，在原代黑素细胞和黑色素瘤细胞系中确定“稀释物”的功能，并识别与“稀释物”相互作用的蛋白质。2，在培养细胞和转基因小鼠中，利用与“稀释物”肌球蛋白(myosin-Va)及其近亲MYR 6(myosin-Vb)嵌合的cDNA构建，识别“稀释物”肌球蛋白尾部赋予货物结合特异性的区域。

The murine "dilute" unconventional myosin (Myo5a) locus provides an outstanding genetic system to study molecular motor-cargo interactions and overlapping functions of closely related members of unconventional myosin families. Several aspects of the "dilute" system contribute to a powerful approach to answering these questions: the availability of multiple mutant alleles at the "dilute" locus and the "ashen," "leaden," and "dilute suppressor" loci; the recent characterization by Mercer of a second mammalian member of the "dilute" family, myr 6 (Myo5b); the ability to manipulate the genome of the mouse; and the availability of a primary melanocyte cell culture system that provides a visual assay for "dilute" myosin function. The studies will impact the organelle transport field by providing insights into motor-cargo interactions and testing for functional redundancy within an unconventional myosin family.The studies have the following objectives:1, Determine the functions of "dilute" and identify proteins that interact with "dilute" in both primary melanocyte and melanoma cell lines, using cell biological, biochemical, and genetic methods.2, Identify regions of the "dilute" myosin tail that confer cargo-binding specificity using chimeric cDNA constructs with portions of the "dilute" myosin (myosin-Va) and its close relative, myr 6 (myosin-Vb), in both cultured cells and in transgenic mice.