KCHIP1蛋白的两个新功能域研究

Homo sapiens Kv channel interacting protein 1(KCHIP1)基因表达蛋白是新,发现的神经钙离子结合蛋白超家族中的一个新成员。本文利用定点突变和荧光定位等技术,证实KCHIP1蛋白具有钙离子结合域和肉豆蔻酰化位点两个显著的结构特点,同时发现了KCHIP1蛋白两个对肉豆蔻酰化有重要意义的肉豆蔻酰化位点G2A和G6A。

Experimental study on the new significant function domains of KCHIP1 protein

Human Kv channel interacting protein 1 (KCHIP1) is a new member of the neural calcium binding protein superfamily.Theoretically KCHIP1 has several calcium binding domains and two myristoylation sites. In this study, we demonstrated that thecalcium binding domains and myristoylation sites were functional. The first, through running SDS-PAGE gel, we testified its ability ofbinding Ca2+ with obvious discrepancy of the electrophoresis migrating rate after binding Ca2+. Then, through the techniques of fusedgreen fluorescence protein and site-directed mutagenesis, we demonstrated that wild type KCHIP1 protein accumulated in the secre-tory vesicles of Golgi body. In contrast, its two mutated forms without myristoylation sites accumulated throughout the wholecytoplasm. These observations indicate that KCHIP1 protein has a myristoylation motif mediating the interaction between KCHIP1protein and membrane.