拟南芥悬浮培养细胞外钙结合蛋白的初步检测

Detection of Ca^(2+)-binding Proteins in Extracellular Proteins Extracted from Suspension-cultured Cells of Arabidopsis thaliana

钙离子通过与其结合的蛋白质在植物细胞信号转导中起着重要的作用,已知植物细胞外空间钙离子浓度高达毫摩尔级,而与钙结合的胞外蛋白有待进一步的分析研究.采用丙酮沉淀法分别制备了拟南芥悬浮培养细胞壁盐提蛋白及培养介质蛋白,制备的蛋白经SDS PAGE电泳分离后,电转移至硝酸纤维素膜,45Ca2+覆盖结合,放射自显影,结果表明悬浮细胞外可能存在多条可与钙离子结合的蛋白条带,其分子量约为17,30,40,68 ku,推测这些蛋白可能参与胞外钙离子相关的生物学过程.

Calcium plays important roles in cell signal transduction,and Ca^2＋-binding proteins participate in various activities. There is much Ca^2＋ in extracellular space than that in cytoplasm, so the researches on extracellular Ca^2＋-binding proteins has an important meaning. First, extracellular proteins were prepared from the suspension-cultured cells of Arabidopsis thaliana, then separated by SDS-PAGE and transferred to nitrocellulose membranes. The membranes were blotted with 45CAC12, and then exposed to phosphimager. Four protein bands each with molecular weight about 17,30,40,68 ku were shown. These proteins may function extracellularly with Ca^2＋ .