Abstract:
Unconventional myosins are a superfamily of actin-based motor proteins that perform a number of roles in fundamental cellular processes, including (but not limited to) intracellular trafficking, cell motility, endocytosis, exocytosis and cytokinesis. 40 myosins genes have been identified in humans, which belong to different 12 classes based on their domain structure and organisation. These genes are widely expressed in different tissues, and mutations leading to loss of function are associated with a wide variety of pathologies while over-expression often results in cancer. Caenorhabditis elegans (C. elegans) is a small, free-living, non-parasitic nematode. ~38% of the genome of C. elegans has predicted orthologues in the human genome, making it a valuable tool to study the function of human counterparts and human diseases. To date, 8 unconventional myosin genes have been identified in the nematode, from 6 different classes with high homology to human paralogues. The hum-1 and hum-5 (heavy chain of an unconventional myosin) genes encode myosin of class I, hum-2 of class V, hum-3 and hum-8 of class VI, hum-6 of class VII and hum-7 of class IX. The hum-4 gene encodes a high molecular mass myosin (307 kDa) that is one of the most highly divergent myosins and is a member of class XII. Mutations in many of the human orthologues are lethal, indicating their essential properties. However, a functional characterisation for many of these genes in C. elegans has not yet been performed. This article reviews the current knowledge of unconventional myosin genes in C. elegans and explores the potential use of the nematode to study the function and regulation of myosin motors to provide valuable insights into their role in diseases.
摘要:
非常规肌球蛋白是基于肌动蛋白的运动蛋白的超家族,在基本细胞过程中发挥许多作用,包括(但不限于)细胞内贩运,细胞运动性,内吞作用,胞吐和胞质分裂。已经在人类中鉴定出40个肌球蛋白基因,根据它们的领域结构和组织,它们属于不同的12类。这些基因在不同的组织中广泛表达,导致功能丧失的突变与多种病理有关,而过度表达通常会导致癌症。秀丽隐杆线虫(C.线虫)是一个小,自由生活,非寄生线虫。约38%的C.elegans基因组已预测人类基因组中的直系同源物,使其成为研究人类同伴和人类疾病功能的有价值的工具。迄今为止,已经在线虫中鉴定出8个非常规的肌球蛋白基因,来自6个不同的类别,与人类旁系同源物具有高度同源性。hum-1和hum-5(非常规肌球蛋白的重链)基因编码I类肌球蛋白,V级的嗡嗡声-2,六类的嗡嗡声3和嗡嗡声8,第VII类的嗡嗡声-6和第IX类的嗡嗡声-7。hum-4基因编码高分子量肌球蛋白(307kDa),它是最高度发散的肌球蛋白之一并且是XII类的成员。许多人类直系同源物的突变是致命的,表明其基本特征。然而,秀丽隐杆线虫中许多这些基因的功能表征尚未进行。本文回顾了线虫中非常规肌球蛋白基因的最新知识,并探讨了线虫在研究肌球蛋白运动的功能和调节方面的潜在用途,从而为其在疾病中的作用提供有价值的见解。