Marine Adlanmerini1, Febrissy Chanaelle1, Rana Zahreddine1, Emilie Vessières2, Mélissa Buscato1, Romain Solinhac1, Julie Favre1,2, Typhaine Anquetil1, Anne-Laure Guihot2, Frederic Boudou1, Isabelle Raymond-Letron3, Pierre Chambon4, Pierre Gourdy1, Claes Ohlsson5, Henrik Laurell1, Coralie Fontaine1, Raphael Metivier6, Muriel Le Romancer7, Daniel Henrion2, Jean-Francois Arnal1, Francoise Lenfant1. 1. From the INSERM-UPS UMR U1048, Institut des Maladies Métaboliques et Cardiovasculaires, Universite de Toulouse, France (M.A., F.C., R.Z., M.B., R.S., T.A., F.B., P.G., H.L., C.F., J.F.A., F.L.). 2. Institut National de la Santé et de la Recherche Médicale U1083, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 46 015, Université d'Angers, France (E.V., J.F., A.L.G., D.H.). 3. Institut National Polytechnique, École Nationale Vétérinaire de Toulouse, Institut National de la Santé et de la Recherche Médicale, Unité Mixte de Service 006, Universite de Toulouse, France (I.R.-L.). 4. Institut de Génétique et de Biologie Moléculaire et Cellulaire, Collège de France, Universitéde Strasbourg, Illkirch, France (P.C.). 5. Centre for Bone and Arthritis Research Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Sweden (C.O.). 6. CNRS, Université de Rennes, IGDR (Institut de Génétique De Rennes) - UMR 6290, France (R.M.). 7. Inserm U1052, CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, France (M.L.R.).
Abstract
OBJECTIVE: ERα (estrogen receptor alpha) exerts nuclear genomic actions and also rapid membrane-initiated steroid signaling. The mutation of the cysteine 451 into alanine in vivo has recently revealed the key role of this ERα palmitoylation site on some vasculoprotective actions of 17β-estradiol (E2) and fertility. Here, we studied the in vivo role of the arginine 260 of ERα which has also been described to be involved in its E2-induced rapid signaling with PI3-Kinase as well as G protein in cultured cell lines. Approach and Results: We generated a mouse model harboring a point mutation of the murine counterpart of this arginine into alanine (R264A-ERα). In contrast to the C451A-ERα, the R264A-ERα females are fertile with standard hormonal serum levels and normal control of hypothalamus-pituitary ovarian axis. Although R264A-ERα protein abundance was normal, the well-described membrane ERα-dependent actions of estradiol, such as the rapid dilation of mesenteric arteries and the acceleration of endothelial repair of carotid, were abrogated in R264A-ERα mice. In striking contrast, E2-regulated gene expression was highly preserved in the uterus and the aorta, revealing intact nuclear/genomic actions in response to E2. Consistently, 2 recognized nuclear ERα-dependent actions of E2, namely atheroma prevention and flow-mediated arterial remodeling were totally preserved. CONCLUSIONS: These data underline the exquisite role of arginine 264 of ERα for endothelial membrane-initiated steroid signaling effects of E2 but not for nuclear/genomic actions. This provides the first model of fertile mouse with no overt endocrine abnormalities with specific loss-of-function of rapid ERα signaling in vascular functions.
OBJECTIVE: ERα (estrogen receptor alpha) exerts nuclear genomic actions and also rapid membrane-initiated steroid signaling. The mutation of the cysteine 451 into alanine in vivo has recently revealed the key role of this ERα palmitoylation site on some vasculoprotective actions of 17β-estradiol (E2) and fertility. Here, we studied the in vivo role of the arginine 260 of ERα which has also been described to be involved in its E2-induced rapid signaling with PI3-Kinase as well as G protein in cultured cell lines. Approach and Results: We generated a mouse model harboring a point mutation of the murine counterpart of this arginine into alanine (R264A-ERα). In contrast to the C451A-ERα, the R264A-ERα females are fertile with standard hormonal serum levels and normal control of hypothalamus-pituitary ovarian axis. Although R264A-ERα protein abundance was normal, the well-described membrane ERα-dependent actions of estradiol, such as the rapid dilation of mesenteric arteries and the acceleration of endothelial repair of carotid, were abrogated in R264A-ERα mice. In striking contrast, E2-regulated gene expression was highly preserved in the uterus and the aorta, revealing intact nuclear/genomic actions in response to E2. Consistently, 2 recognized nuclear ERα-dependent actions of E2, namely atheroma prevention and flow-mediated arterial remodeling were totally preserved. CONCLUSIONS: These data underline the exquisite role of arginine 264 of ERα for endothelial membrane-initiated steroid signaling effects of E2 but not for nuclear/genomic actions. This provides the first model of fertile mouse with no overt endocrine abnormalities with specific loss-of-function of rapid ERα signaling in vascular functions.