FHL2通过相互作用抑制分化抑制蛋白家族成员的转录抑制活性  

FHL2 Cooperates with Id Family Proteins and Inhibits Their Transcriptional Repression Activities

作　　者：韩为东[1] 赵亚力[1] 伍志强[1] 司艺玲[1] 杨洁[1] 田丽媛[1] 孟元光[2] 

机构地区：[1]解放军总医院基础医学研究所,北京100853 [2]解放军总医院妇产科,北京100853

出　　处：《生物技术通讯》2008年第6期791-794,共4页Letters in Biotechnology

基　　金：国家自然科学基金(30870507);解放军总医院苗圃基金(07MP69)

摘　　要：目的:探讨FHL2与Id(分化抑制蛋白)家族蛋白之间的相互作用及FHL2对Id蛋白功能的调控效应。方法:用GST-pulldown与免疫共沉淀(CoIP)方法检测FHL2与Id家族蛋白成员之间在体内外的相互作用;用共转染与报告基因驱动的萤光素酶方法检测FHL2对Id蛋白介导转录抑制效应的调控作用。结果:FHL2与Id家族的4个蛋白均存在直接的相互作用关系,表位分析结果显示FHL2蛋白中的第2个LIM结构域在FHL2/Id相互作用中是必需的,Id蛋白N端结构域在介导FHL2/Id相互作用中是必需的,FHL2/Id相互作用不依赖于Id蛋白中的螺旋-环-螺旋结构;通过相互作用,FHL2阻止了Id蛋白对碱性螺旋-环-螺旋转录因子E47转录活性的抑制作用。结论:FHL2是一个新识别的Id蛋白广谱的相互作用因子,通过对Id蛋白功能活性的抑制效应,FHL2可能参与Id介导的多种生物学效应以及肿瘤发生与进展。Objective： To investigate the interaction of FHL2 and Id（inhibitor of differentiation） family components and the functional effect of FHL2 on Id2-mediated transcriptional repression. Methods： The interaction of FHL2 and Id family components was measured by GST-pulldoawn and coimmunoprecipitation assays. The regulatory effect of FHL2 on Id proteins-mediated transcriptional repression was determined by cotransfection and luciferase assays. Results：FHL2 directly interacts with all members of Id family, which does not depend on the existence of the helix-loop-helix（HLH） domain con- served within Id proteins. The second LIM domain containing in FHL2 or the N-terminal region in Id proteins are essential for the direct binding of FHL2 and Id proteins. FHL2 represses the inhibitory effect of Id proteins on E47, a ubiquitously expressed basic HLH transcriptional factor, -mediated transcriptional activity. Conclusion： FHL2 is a novel interacting factor of Id proteins. Through cooperating with Id proteins and sequentially repressing their function, FHL2 may involve in the multiple biological effects and tumorogenesis mediated by Id proteins.

关 键 词：FHL2 分化抑制蛋白 相互作用 抑制子 

分 类 号：Q78[生物学—分子生物学] Q25