期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2014
卷号：111
期号：2
页码：E283-E290
DOI：10.1073/pnas.1322057111
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Estrogen receptor alpha (ER) activation functions AF-1 and AF-2 classically mediate gene transcription in response to estradiol (E2). A fraction of ER is targeted to plasma membrane and elicits membrane-initiated steroid signaling (MISS), but the physiological roles of MISS in vivo are poorly understood. We therefore generated a mouse with a point mutation of the palmitoylation site of ER (C451A-ER) to obtain membrane-specific loss of function of ER. The abrogation of membrane localization of ER in vivo was confirmed in primary hepatocytes, and it resulted in female infertility with abnormal ovaries lacking corpora lutea and increase in luteinizing hormone levels. In contrast, E2 action in the uterus was preserved in C451A-ER mice and endometrial epithelial proliferation was similar to wild type. However, E2 vascular actions such as rapid dilatation, acceleration of endothelial repair, and endothelial NO synthase phosphorylation were abrogated in C451A-ER mice. A complementary mutant mouse lacking the transactivation function AF-2 of ER (ER-AF20) provided selective loss of function of nuclear ER actions. In ER-AF20, the acceleration of endothelial repair in response to estrogen-dendrimer conjugate, which is a membrane-selective ER ligand, was unaltered, demonstrating integrity of MISS actions. In genome-wide analysis of uterine gene expression, the vast majority of E2-dependent gene regulation was abrogated in ER-AF20, whereas in C451A-ER it was nearly fully preserved, indicating that membrane-to-nuclear receptor cross-talk in vivo is modest in the uterus. Thus, this work genetically segregated membrane versus nuclear actions of a steroid hormone receptor and demonstrated their in vivo tissue-specific roles.
