Okazaki K, Obata N H, Inoue S, Hidaka H
Department of Pharmacology, Nagoya University School of Medicine, Japan.
Biochem J. 1995 Mar 1;306 ( Pt 2)(Pt 2):551-5. doi: 10.1042/bj3060551.
To clarify the function of neurocalcin delta, an isoform found abundantly in glial cells, we attempted to find its target proteins by using neurocalcin delta-affinity chromatography and the 125I-neurocalcin delta gel-overlay method. The 10, 14, 27, 36 and 50 kDa bands found on SDS/PAGE bound to 125I-neurocalcin delta, and 10, 11, 19, 24, 26, 50 and 70 kDa proteins were eluted from a neurocalcin delta-affinity column in a Ca(2+)-dependent manner. Sequence analysis of proteolytic peptides revealed the following identities: S100 beta (10 kDa), S100 alpha (11 kDa), myelin basic protein (19 kDa), glyceraldehyde-3-phosphate dehydrogenase (36 kDa) and tubulin beta-chain (50 kDa). A zero-length cross-linking study indicated that 1 mol of S100 beta bound to 1 mol of neurocalcin delta. With the gel-overlay method, purified S100 beta protein and calcyclin bound to 125I-neurocalcin delta whereas calgizarrin and calvasculin, other members of the S100 family, did not. These findings suggest that S100 beta is one of the target proteins of neurocalcin delta, and the neurocalcin delta-S100 beta complex may be involved in Ca(2+)-signalling in the glial cell.
为阐明在神经胶质细胞中大量存在的一种亚型——神经钙蛋白δ的功能，我们尝试通过使用神经钙蛋白δ亲和层析法和¹²⁵I -神经钙蛋白δ凝胶覆盖法来寻找其靶蛋白。在SDS/PAGE上发现的10、14、27、36和50 kDa条带与¹²⁵I -神经钙蛋白δ结合，并且10、11、19、24、26、50和70 kDa的蛋白质以Ca²⁺依赖的方式从神经钙蛋白δ亲和柱上洗脱下来。对蛋白水解肽段的序列分析揭示了以下一致性：S100β（10 kDa）、S100α（11 kDa）、髓鞘碱性蛋白（19 kDa）、甘油醛 - 3 - 磷酸脱氢酶（36 kDa）和微管蛋白β链（50 kDa）。零长度交联研究表明1摩尔的S100β与1摩尔的神经钙蛋白δ结合。通过凝胶覆盖法，纯化的S100β蛋白和钙周期蛋白与¹²⁵I -神经钙蛋白δ结合，而S100家族的其他成员钙连接蛋白和血管钙蛋白则不结合。这些发现表明S100β是神经钙蛋白δ的靶蛋白之一，并且神经钙蛋白δ - S100β复合物可能参与神经胶质细胞中的Ca²⁺信号传导。
