Chalovich Joseph M, Schroeter Mechthild M
Department of Biochemistry and Molecular Biology, Brody School of Medicine at East Carolina University, 5E-122 Brody Medical Sciences Building, 600 Moye Blvd, Greenville, NC, 27834, USA.
Department of Physiology, University of Cologne, Robert-Koch-Str. 39, 50931, Cologne, Germany.
Biophys Rev. 2010 Dec;2(4):181-189. doi: 10.1007/s12551-010-0040-5. Epub 2010 Nov 20.
The synaptopodin family of proteins consists of at least 3 members: synaptopodin, the synaptopodin 2 proteins, and the synaptopodin 2-like proteins. Each family member has at least 3 isoforms that are produced by alternative splicing. Synaptopodin family members are basic proteins that are rich in proline and have little regular 2° or 3° structure at physiological temperature, pH and ionic strength. Like other natively unfolded proteins, synaptopodin family members have multiple binding partners including actin and other actin-binding proteins. Several members of the synaptopodin family have been shown to stimulate actin polymerization and to bundle actin filaments either on their own or in collaboration with other proteins. Synaptopodin 2 has been shown to accelerate nucleation of actin filament formation and to induce actin bundling. The actin polymerization activity is inhibited by Ca-calmodulin. Synaptopodin 2 proteins are localized in Z-bands of striated and heart muscle and dense bodies of smooth muscle cells. Depending on the developmental status and stress, at least one member of the synaptopodin family can occupy nuclei of some cells. Members of the synaptopodin 2 subfamily have been implicated in cancers.
突触素蛋白家族至少由3个成员组成：突触素、突触素2蛋白和类突触素2蛋白。每个家族成员至少有3种由可变剪接产生的异构体。突触素家族成员是富含脯氨酸的碱性蛋白，在生理温度、pH值和离子强度下几乎没有规则的二级或三级结构。与其他天然未折叠蛋白一样，突触素家族成员有多个结合伴侣，包括肌动蛋白和其他肌动蛋白结合蛋白。突触素家族的几个成员已被证明能刺激肌动蛋白聚合，并能单独或与其他蛋白协同作用使肌动蛋白丝成束。突触素2已被证明能加速肌动蛋白丝形成的成核过程并诱导肌动蛋白成束。肌动蛋白聚合活性受钙调蛋白抑制。突触素2蛋白定位于横纹肌和心肌的Z带以及平滑肌细胞的致密体中。根据发育状态和应激情况，突触素家族至少有一个成员可存在于某些细胞的细胞核中。突触素2亚家族的成员与癌症有关。
