The trophoblast clock controls transport across placenta in mice

ABSTRACT In mammals, 24-h rhythms of physiology and behavior are organized by a body-wide network clock genes proteins. Despite the well-known function adult circadian system, roles maternal, fetal placental clocks during pregnancy poorly defined. mature mouse placenta, labyrinth zone (LZ) is origin key for selective nutrient waste exchange. Recently, gene expression has been detected in LZ other tissues; however, there no evidence controlled clock. Here, we demonstrate that specifically trophoblast layer harbors an already functional late gestation, able to regulate manner activity xenobiotic efflux pump, ATP-binding cassette sub-family B member 1 (ABCB1), likely gating exposure drugs from maternal circulation certain times day. As more than 300 endogenous exogenous compounds substrates ABCB1, our results might have implications choosing treatment time when aiming either maximal/minimal drug availability fetus/mother.