Ruff-Jamison S, Chen K, Cohen S
Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA.
Proc Natl Acad Sci U S A. 1995 May 9;92(10):4215-8. doi: 10.1073/pnas.92.10.4215.
Intraperitoneal injection of epidermal growth factor into mice results in the appearance of multiple tyrosine-phosphorylated proteins in liver nuclei within minutes after administration. We have previously identified three of these proteins as Stat 1 alpha, Stat 1 beta (p91, p84), and Stat 3 (p89). In the present report we demonstrate that Stat 5 (p92), the recently described prolactin inducible transcription factor detected in mammary glands, is the major tyrosine-phosphorylated protein translocated to the nucleus in mouse liver in response to epidermal growth factor. Furthermore, gel-shift analysis and affinity purification revealed that Stat 5, Stat 1 alpha, and Stat 1 beta specifically bind to the prolactin inducible element upstream of the beta-casein promoter.
给小鼠腹腔注射表皮生长因子后，在给药后数分钟内肝脏细胞核中就会出现多种酪氨酸磷酸化蛋白。我们之前已鉴定出其中三种蛋白为Stat 1α、Stat 1β（p91、p84）和Stat 3（p89）。在本报告中，我们证明Stat 5（p92），即最近在乳腺中检测到的催乳素诱导转录因子，是响应表皮生长因子而转运至小鼠肝脏细胞核中的主要酪氨酸磷酸化蛋白。此外，凝胶迁移分析和亲和纯化显示，Stat 5、Stat 1α和Stat 1β特异性结合β-酪蛋白启动子上游的催乳素诱导元件。
