Tyrosine phosphorylation controls nuclear localization and transcriptional activity of Ssdp1 in mammalian cells.
Tyrosine phosphorylation controls nuclear localization and transcriptional activity of Ssdp1 in mammalian cells.
复制标题
酪氨酸磷酸化控制哺乳动物细胞中 Ssdp1 的核定位和转录活性。
DOI：
10.1002/jcb.21576
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发表时间：
2008
影响因子：
4
通讯作者：
Westphal,Heiner
中科院分区：
文献类型：
--
作者：
Dey-Guha,Ipsita;Malik,Nasir;Lesourne,Renaud;Love,PaulE;Westphal,Heiner
LIM-HD蛋白与不同的辅因子相互作用，包括Ssdp 1，以调节各种物种的发育。单链DNA结合蛋白（Ssdp 1）是一个进化上保守的蛋白质家族的成员，在胚胎发育过程中调节关键的转录过程。Ssdp 1主要定位于293 T细胞的细胞质中，但当与非受体酪氨酸激酶Src家族的成员Lck共转染时，Ssdp 1易位至细胞核。Src酪氨酸激酶抑制剂PP 2阻断了Ssdp 1的核转位。Western blot分析表明，Ssdp 1和Lck在293 T细胞中的共表达诱导Ssdp 1磷酸化。突变的Ssdp 1 N端酪氨酸残基23和25显着降低磷酸化和核定位的Ssdp 1。Lck增强了Ssdp 1在LIM-同源结构域（LIM-HD）/辅因子复合物的已知组分的背景下的转录活性。我们提出，涉及Ssdp 1的N末端酪氨酸残基的磷酸化是调节其核定位和随后的LIM-HD复合物转录激活的一种手段。J.细胞。103：1856-1865，2007.© 2007 Wiley利斯公司
The LIM‐HD proteins interact with different cofactors, including Ssdp1 to regulate development in a diverse range of species. The single stranded DNA binding protein (Ssdp1) is a member of an evolutionarily conserved family of proteins that regulate critical transcriptional processes during embryonic development. Ssdp1 is localized predominantly in the cytoplasm of 293T cells but is translocated to the nucleus when co‐transfected with Lck, a member of the Src family of non‐receptor tyrosine kinases. The Src tyrosine kinase inhibitor PP2 blocked the nuclear translocation of Ssdp1. Western blot analysis showed that co‐expression of Ssdp1 and Lck in 293T cells induces Ssdp1 phosphorylation. Mutation of the Ssdp1 N terminal tyrosine residues 23 and 25 markedly reduced both the phosphorylation and the nuclear localization of Ssdp1. Lck enhanced the transcriptional activity of Ssdp1 in the context of known components of a LIM‐homeodomain (LIM‐HD)/cofactor complex. We propose that phosphorylation involving N‐terminal tyrosine residues of Ssdp1 is a means of regulating its nuclear localization and subsequent transcriptional activation of LIM‐HD complexes. J. Cell. Biochem. 103: 1856–1865, 2007. © 2007 Wiley‐Liss, Inc.