含羞草质膜内在蛋白的水通道活性受直接相互作用和磷酸化调节。

Water channel activities of Mimosa pudica plasma membrane intrinsic proteins are regulated by direct interaction and phosphorylation.

作者信息

Temmei Yusuke, Uchida Shinichi, Hoshino Daisuke, Kanzawa Nobuyuki, Kuwahara Michio, Sasaki Sei, Tsuchiya Takahide

机构信息

Department of Chemistry, Faculty of Science and Technology, Sophia University, 7-1 Kioi, Chiyoda-ku, Tokyo 102-8554, Japan.

出版信息

FEBS Lett. 2005 Aug 15;579(20):4417-22. doi: 10.1016/j.febslet.2005.06.082.

DOI:10.1016/j.febslet.2005.06.082

PMID:16061230

Abstract

cDNAs encoding aquaporins PIP1;1, PIP2;1, and TIP1;1 were isolated from Mimosa pudica (Mp) cDNA library. MpPIP1;1 exhibited no water channel activity; however, it facilitated the water channel activity of MpPIP2;1 in a phosphorylation-dependent manner. Mutagenesis analysis revealed that Ser-131 of MpPIP1;1 was phosphorylated by PKA and that cooperative regulation of the water channel activity of MpPIP2;1 was regulated by phosphorylation of Ser-131 of MpPIP1;1. Immunoprecipitation analysis revealed that MpPIP1;1 binds directly to MpPIP2;1 in a phosphorylation-independent manner, suggesting that phosphorylation of Ser-131 of MpPIP1;1 is involved in regulation of the structure of the channel complex with MpMIP2;1 and thereby affects water channel activity.

摘要

从含羞草（Mimosa pudica，Mp）cDNA文库中分离出编码水通道蛋白PIP1;1、PIP2;1和TIP1;1的cDNA。MpPIP1;1不表现出水通道活性；然而，它以磷酸化依赖的方式促进MpPIP2;1的水通道活性。诱变分析表明，MpPIP1;1的Ser-131被蛋白激酶A磷酸化，并且MpPIP2;1水通道活性的协同调节受MpPIP1;1的Ser-131磷酸化调控。免疫沉淀分析表明，MpPIP1;1以磷酸化非依赖的方式直接与MpPIP2;1结合，这表明MpPIP1;1的Ser-131磷酸化参与了与MpMIP2;1通道复合物结构的调节，从而影响水通道活性。