Donato R
Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Italy.
Cell Calcium. 1991 Nov;12(10):713-26. doi: 10.1016/0143-4160(91)90040-l.
The S-100 protein family constitutes a subgroup of Ca(2+)-binding proteins of the EF-hand type comprising three dimeric isoforms, S-100a0, S-100a and S-100b, plus a number of structurally related proteins displaying 28-55% homology with S-100 subunits. S-100 protein was discovered in 1965; yet, its biological functions have not been fully elucidated. The present report will review the putative biological roles of S-100 protein. Both intracellular and extracellular roles have been proposed for S-100 protein. Within cells, S-100 protein has been reported to regulate protein phosphorylation, ATPase, adenylate cyclase, and aldolase activities and Ca(2+)-induced Ca2+ release. Also, cytoskeletal systems, namely microtubules and microfilaments have been reported to be regulated by the protein in the presence of Ca2+. Some molecular targets of S-100 protein within cells, have been identified. This is the case with microtubule proteins, caldesmon, and a brain aldolase. S-100 protein has been reported to be secreted; extracellular S-100 protein can stimulate neuronal differentiation, glial proliferation, and prolactin secretion. However, the mechanisms by which S-100 is secreted and stimulates the above processes are largely unknown. Future research should characterize these latter aspects of S-100 biology and find out the linkage between its intracellular effects and its extracellular activities.
S-100蛋白家族是EF手型钙结合蛋白的一个亚组，由三种二聚体异构体S-100a0、S-100a和S-100b组成，外加一些与S-100亚基具有28%-55%同源性的结构相关蛋白。S-100蛋白于1965年被发现；然而，其生物学功能尚未完全阐明。本报告将综述S-100蛋白假定的生物学作用。S-100蛋白在细胞内和细胞外均发挥作用。据报道，在细胞内，S-100蛋白可调节蛋白质磷酸化、ATP酶、腺苷酸环化酶和醛缩酶的活性以及钙诱导的钙释放。此外，据报道，在钙离子存在的情况下，细胞骨架系统，即微管和微丝受该蛋白调节。已确定S-100蛋白在细胞内的一些分子靶点，如微管蛋白、钙调蛋白和脑醛缩酶。据报道，S-100蛋白可分泌；细胞外的S-100蛋白可刺激神经元分化、神经胶质细胞增殖和催乳素分泌。然而，S-100蛋白分泌并刺激上述过程的机制在很大程度上尚不清楚。未来的研究应明确S-100生物学的这些方面，并找出其细胞内效应与细胞外活性之间的联系。
