Department of Cardiology, The 4th Affiliated Hospital of Harbin Medical University, 150001, Harbin, Peoples Republic of China.
Mol Biol Rep. 2010 Oct;37(7):3481-5. doi: 10.1007/s11033-009-9940-5. Epub 2009 Dec 1.
CalDAGs are a family of Ras guanyl exchange factors that contain calcium and DAG-binding domains. Among the four identified members of CalDAG family, CalDAGIII has been shown to play important role in B lymphocyte and endocrine cell functions. However, the mechanism underlining these functions remain to be determined. Here in the present study, we determined the subcellular localization of CalDAGIII and roles of calcium-binding and DAG-binding domains in its localization. We found that C1 domain but not EF hands is important for both CalDAGIII localization to the Golgi and p38 activation in B cells, indicating that CalDAGIII may be regulated by DAG but not calcium.
CalDAGs 是 Ras 鸟苷酸交换因子家族的一员，含有钙和 DAG 结合域。在已鉴定的 CalDAG 家族的四个成员中，CalDAGIII 已被证明在 B 淋巴细胞和内分泌细胞功能中发挥重要作用。然而，这些功能背后的机制仍有待确定。在本研究中，我们确定了 CalDAGIII 的亚细胞定位以及钙结合和 DAG 结合域在其定位中的作用。我们发现 C1 结构域而非 EF 手对 CalDAGIII 向高尔基体的定位和 B 细胞中 p38 的激活都是重要的，这表明 CalDAGIII 可能受到 DAG 的调节而不是钙。
