Chen Huaiyang, Duncan Ian C, Bozorgchami Hormozd, Lo Su Hao
Center for Tissue Regeneration and Repair, Department of Orthopaedic Surgery, University of California at Davis, Sacramento, CA 95817, USA.
Proc Natl Acad Sci U S A. 2002 Jan 22;99(2):733-8. doi: 10.1073/pnas.022518699. Epub 2002 Jan 15.
Tensin is a focal adhesion molecule that binds to actin filaments and participates in signaling pathways. In this study, we have characterized a previously undocumented tensin family member, tensin2/KIAA 1075. Human tensin2 cDNA encodes a 1,285-aa sequence that shares extensive homology with tensin1 at its amino- and carboxyl-terminal ends, which include the actin-binding domain, the Src homology 2 (SH2) domain, and the phosphotyrosine binding (PTB) domain. Analysis of the genomic structures of tensin1 and tensin2 further confirmed that they represent a single gene family. Examination of tensin2 mRNA distribution revealed that heart, kidney, skeletal muscle, and liver were tissues of high expression. The endogenous and recombinant tensin2 were expressed as a 170-kDa protein in NIH 3T3 cells. The subcellular localization of tensin2 was determined by transfection of green fluorescence protein (GFP)-tensin2 fusion construct. The results indicated that tensin2 is also localized to focal adhesions. Finally, functional analysis of tensin genes has demonstrated that expression of tensin genes is able to promote cell migration on fibronectin, indicating that the tensin family plays a role in regulating cell motility.
张力蛋白是一种与肌动蛋白丝结合并参与信号通路的粘着斑分子。在本研究中，我们鉴定了一个此前未被报道的张力蛋白家族成员，即张力蛋白2/KIAA 1075。人类张力蛋白2 cDNA编码一个1285个氨基酸的序列，该序列在其氨基末端和羧基末端与张力蛋白1具有广泛的同源性，其中包括肌动蛋白结合结构域、Src同源2（SH2）结构域和磷酸酪氨酸结合（PTB）结构域。对张力蛋白1和张力蛋白2基因组结构的分析进一步证实它们代表一个单一的基因家族。对张力蛋白2 mRNA分布的检测显示，心脏、肾脏、骨骼肌和肝脏是高表达组织。内源性和重组的张力蛋白2在NIH 3T3细胞中表达为一种170 kDa的蛋白质。通过转染绿色荧光蛋白（GFP）-张力蛋白2融合构建体来确定张力蛋白2的亚细胞定位。结果表明，张力蛋白2也定位于粘着斑。最后，对张力蛋白基因的功能分析表明，张力蛋白基因的表达能够促进细胞在纤连蛋白上的迁移，这表明张力蛋白家族在调节细胞运动中发挥作用。
