Cytosolic Ca^(2+)as a multifunctional modulator is required for spermiogenesis in Ascaris suum  

作　　者：Yunlong Shang Lianwan Chen Zhiyu Liu Xia Wang Xuan Ma Long Miao 

机构地区：[1]Laboratory of Noncoding RNA,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China [2]University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Protein & Cell》2013年第6期456-466,共11页蛋白质与细胞（英文版）

基　　金：the National Basic Research Program(973 Program)(Nos.2012CB945002 and 2010CB912303)and 31171337 from the Chinese government.

摘　　要：The dynamic polar polymers actin fi laments and microtu-bules are usually employed to provide the structural ba-sis for establishing cell polarity in most eukaryotic cells.Radially round and immotile spermatids from nematodes contain almost no actin or tubulin,but still have the abil-ity to break symmetry to extend a pseudopod and initiate the acquisition of motility powered by the dynamics of cytoskeleton composed of major sperm protein(MSP)during spermiogenesis(sperm activation).However,the signal transduction mechanism of nematode sperm activation and motility acquisition remains poorly under-stood.Here we show that Ca^(2+) oscillations induced by the Ca^(2+) release from intracellular Ca^(2+) store through inositol(1,4,5)-trisphosphate receptor are required for Ascaris suum sperm activation.The chelation of cytosolic Ca^(2+) suppresses the generation of a functional pseudopod,and this suppression can be relieved by introducing ex-ogenous Ca^(2+) into sperm cells.Ca^(2+) promotes MSP-based sperm motility by increasing mitochondrial membrane potential and thus the energy supply required for MSP cytoskeleton assembly.On the other hand,Ca^(2+) promotes MSP disassembly by activating Ca^(2+)/calmodulin-depend-ent serine/threonine protein phosphatase calcineurin.In addition,Ca^(2+)/camodulin activity is required for the fusion of sperm-specifi c membranous organelle with the plasma membrane,a regulated exocytosis required for sperm mo-tility.Thus,Ca^(2+)plays multifunctional roles during sperm activation in Ascaris suum.

关 键 词：SPERMIOGENESIS CA^(2+) major sperm protein Ascaris suum 

分 类 号：R69[医药卫生—泌尿科学]