<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Alvarez, J D</style></author><author><style face="normal" font="default" size="100%">Hansen, Amanda</style></author><author><style face="normal" font="default" size="100%">Ord, Teri</style></author><author><style face="normal" font="default" size="100%">Bebas, Piotr</style></author><author><style face="normal" font="default" size="100%">Chappell, Patrick E</style></author><author><style face="normal" font="default" size="100%">Giebultowicz, Jadwiga M</style></author><author><style face="normal" font="default" size="100%">Williams, Carmen</style></author><author><style face="normal" font="default" size="100%">Moss, Stuart</style></author><author><style face="normal" font="default" size="100%">Sehgal, Amita</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The circadian clock protein BMAL1 is necessary for fertility and proper testosterone production in mice.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of biological rhythms</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Rhythms</style></alt-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Animals</style></keyword><keyword><style  face="normal" font="default" size="100%">ARNTL Transcription Factors</style></keyword><keyword><style  face="normal" font="default" size="100%">Basic Helix-Loop-Helix Transcription Factors</style></keyword><keyword><style  face="normal" font="default" size="100%">Blotting, Western</style></keyword><keyword><style  face="normal" font="default" size="100%">Cells, Cultured</style></keyword><keyword><style  face="normal" font="default" size="100%">Circadian Rhythm</style></keyword><keyword><style  face="normal" font="default" size="100%">Fertility</style></keyword><keyword><style  face="normal" font="default" size="100%">Fertilization in Vitro</style></keyword><keyword><style  face="normal" font="default" size="100%">Follicle Stimulating Hormone</style></keyword><keyword><style  face="normal" font="default" size="100%">Hormones</style></keyword><keyword><style  face="normal" font="default" size="100%">Immunohistochemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Infertility</style></keyword><keyword><style  face="normal" font="default" size="100%">Luciferases</style></keyword><keyword><style  face="normal" font="default" size="100%">Luteinizing Hormone</style></keyword><keyword><style  face="normal" font="default" size="100%">Male</style></keyword><keyword><style  face="normal" font="default" size="100%">Mice</style></keyword><keyword><style  face="normal" font="default" size="100%">Mice, Inbred C57BL</style></keyword><keyword><style  face="normal" font="default" size="100%">Mice, Knockout</style></keyword><keyword><style  face="normal" font="default" size="100%">Reverse Transcriptase Polymerase Chain Reaction</style></keyword><keyword><style  face="normal" font="default" size="100%">RNA</style></keyword><keyword><style  face="normal" font="default" size="100%">Sperm Capacitation</style></keyword><keyword><style  face="normal" font="default" size="100%">Sperm Count</style></keyword><keyword><style  face="normal" font="default" size="100%">Testosterone</style></keyword><keyword><style  face="normal" font="default" size="100%">Transfection</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">26-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although it is well established that the circadian clock regulates mammalian reproductive physiology, the molecular mechanisms by which this regulation occurs are not clear. The authors investigated the reproductive capacity of mice lacking Bmal1 (Arntl, Mop3), one of the central circadian clock genes. They found that both male and female Bmal1 knockout (KO) mice are infertile. Gross and microscopic inspection of the reproductive anatomy of both sexes suggested deficiencies in steroidogenesis. Male Bmal1 KO mice had low testosterone and high luteinizing hormone serum concentrations, suggesting a defect in testicular Leydig cells. Importantly, Leydig cells rhythmically express BMAL1 protein, suggesting peripheral control of testosterone production by this clock protein. Expression of steroidogenic genes was reduced in testes and other steroidogenic tissues of Bmal1 KO mice. In particular, expression of the steroidogenic acute regulatory protein (StAR) gene and protein, which regulates the rate-limiting step of steroidogenesis, was decreased in testes from Bmal1 KO mice. A direct effect of BMAL1 on StAR expression in Leydig cells was indicated by in vitro experiments showing enhancement of StAR transcription by BMAL1. Other hormonal defects in male Bmal1 KO mice suggest that BMAL1 also has functions in reproductive physiology outside of the testis. These results enhance understanding of how the circadian clock regulates reproduction.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18258755?dopt=Abstract</style></custom1></record></records></xml>