Non-classical mechanisms of steroid sensing in the ovary: Lessons from the bovine oxytocin model

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• 作者：Richard Ivell ; Yanzhenzi Dai ; Navdeep Mann ; Ravinder An ; -Ivell
• 关键词：Oxytocin ; Non-classical steroid signaling ; Oxytocin receptor ; Estrogen receptor-alpha ; Estrogen receptor-beta ; Bovine ovary
• 刊名：Molecular and Cellular Endocrinology
• 出版年：25 January, 2014
• 年：2014
• 卷：382
• 期：1
• 页码：466-471
• 全文大小：527 K

文摘

Steroidogenic tissues such as the ovary, testes or adrenal glands are paradoxical in that they often indicate actions of steroid hormones within a dynamic range of ligand concentration in a high nanomolar or even micromolar level, i.e. at the natural concentrations existing within those organs. Yet ligand-activated nuclear steroid receptors act classically by direct interaction with DNA in the picomolar or low nanomolar range. Moreover, global genomic studies suggest that less than 40% of steroid-regulated genes involve classical responsive elements in gene promoter regions. The bovine oxytocin gene is a key element in the maternal recognition of pregnancy in ruminants and is regulated via an SF1 site in its proximal promoter. This gene is also regulated by steroids acting in a non-classical manner, involving nuclear receptors which do not interact directly with DNA. Dose-response relationships for these actions are in the high nanomolar range. Similar 鈥榮teroid sensing鈥?mechanisms may prevail for other SF1-regulated genes and predict alternative pathways by which environmental endocrine disruptors might influence the functioning of steroid-producing organs and hence indirectly the steroid-dependent control of physiology and development.