Zhang Li-Hua, McManus Donald P, Sunderland Philip, Lu Xiao-Mei, Ye Jian-Jun, Loukas Alex, Jones Malcolm K
Australian Centre for International and Tropical Health and Nutrition, The Queensland Institute of Medical Research, Herston, Qld. 4029, Australia.
Int J Biochem Cell Biol. 2005 Jul;37(7):1511-24. doi: 10.1016/j.biocel.2005.01.015.
Schistosomes are pathogenic helminth parasites of human portal veins. Their body wall is a highly active syncytial tegument involved in an array of host interactions. The cytoskeletal organization and dynamics of this syncytium are poorly understood, but predominant motor components are the LC8 class of cytoplasmic dynein light chains (DLC). Four LC8 members occur in schistosomes, two of which are expressed in the tegument. Here, we describe the cytoplasmic distribution, stage-specific expression and cellular location of two diverse LC8 molecules of Schistosoma japonicum. SjDLC1 was detected in surface-membrane specific extracts of adult worms and was shown by quantitative immuno-electron microscopy to predominate along heptalaminate membranes of the worm surface. SjDLC3 also occurs in the tegument, but was shown to be present in basal layers of the tegument and did not preferentially co-localize with particular membrane components. SjDLC3 was also detected in the gastrodermis. SjDLC1 is expressed only in mammalian-parasitic stages, whereas SjDLC3 is expressed throughout the life-cycle. The data suggest that SjDLC1 is preferentially located to the host-interactive distal parasite membrane, and plays a role in surface membrane dynamics, while SjDLC3 is a ubiquitous motor component of schistosome epithelia of all stages.
血吸虫是人类门静脉的致病性蠕虫寄生虫。它们的体壁是一种高度活跃的合胞体被膜，参与一系列宿主相互作用。人们对这种合胞体的细胞骨架组织和动力学了解甚少，但主要的运动成分是胞质动力蛋白轻链（DLC）的LC8类。血吸虫中有四个LC8成员，其中两个在被膜中表达。在这里，我们描述了日本血吸虫两种不同LC8分子的胞质分布、阶段特异性表达和细胞定位。在成虫的表面膜特异性提取物中检测到SjDLC1，定量免疫电子显微镜显示其在虫体表面的七叠层膜上占主导地位。SjDLC3也存在于被膜中，但显示存在于被膜的基底层，且不优先与特定膜成分共定位。在胃皮层中也检测到了SjDLC3。SjDLC1仅在寄生哺乳动物阶段表达，而SjDLC3在整个生命周期中都有表达。数据表明，SjDLC1优先定位于与宿主相互作用的寄生虫远端膜，并在表面膜动力学中发挥作用，而SjDLC3是血吸虫各阶段上皮细胞中普遍存在的运动成分。
