Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, 133-791, Korea.
Mol Cells. 2010 Sep;30(3):255-62. doi: 10.1007/s10059-010-0116-x. Epub 2010 Aug 23.
C. elegans coelomocytes are macrophage-like scavenger cells that provide an excellent in vivo system for the study of clathrin-mediated endocytosis. Using this in vivo system, several genes involved in coelomocyte endocytosis have been identified previously. However, the detailed mechanism of endocytic pathway is still unknown. Here, we report a new function of calcineurin, an evolutionarily conserved Ca(2+)/calmodulin-dependent Ser/Thr protein phosphatase, in coelomocyte endocytosis. We found that calcineurin mutants show defective coelomocyte endocytosis. Genetic analysis suggests that calcineurin and a GTPase, dynamin (DYN-1), may function upstream of an orphan receptor, CUP-4, to regulate endocytosis. Therefore, we propose a model in which calcineurin may regulate coelomocyte endocytosis via DYN-1 and CUP-4 in C. elegans.
秀丽隐杆线虫体腔细胞是类似于巨噬细胞的清道夫细胞，为研究网格蛋白介导的胞吞作用提供了极好的体内系统。使用该体内系统，先前已经鉴定出几个参与体腔细胞胞吞作用的基因。然而，内吞途径的详细机制仍不清楚。在这里，我们报道钙调神经磷酸酶（一种进化上保守的 Ca（2+）/钙调蛋白依赖性 Ser/Thr 蛋白磷酸酶）在体腔细胞胞吞作用中的新功能。我们发现钙调神经磷酸酶突变体显示出体腔细胞胞吞作用缺陷。遗传分析表明，钙调神经磷酸酶和 GTPase，动力蛋白（DYN-1）可能在上游作用于一个孤儿受体 CUP-4，以调节内吞作用。因此，我们提出了一个模型，即钙调神经磷酸酶可能通过 C. elegans 中的 DYN-1 和 CUP-4 来调节体腔细胞的胞吞作用。
