EXPRESSION AND LOCALIZATION OF UROKINASE-TYPE PLASMINOGEN ACTIVATOR RECEPTOR IN BOVINE CUMULUS-OOCYTE COMPLEXES

DANIELA C. GARCÍA; DORA C. MICELI; GABRIELA RIZO; ELINA V. GARCÍA; PABLO A. VALDECANTOS; MARIELA ROLDÁN-OLARTE

ZYGOTE

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2015 vol. 24 p. 230 - 235

0967-1994

Urokinase-type plasminogen activator (uPA) is a serine protease involved in extracellular matrix remodeling through plasmin generation. uPA usually binds to its receptor, uPAR, which is anchored to the plasma membrane through a glycosylphosphatidylinositol anchor. uPA/uPAR binding increases proteolytic activity in the neighborhood of the cells containing uPAR and activates intracellular signaling pathways involved in extracellular matrix remodeling, cell migration and proliferation. The aim of this work was to study the expression of uPA, uPAR and plasminogen activator inhibitor-1 (PAI-1) in immature and in vitro matured bovine cumulus-oocyte complexes (COCs). uPA is only expressed in the cumulus cells of immature and in vitro matured COCs, while uPAR and PAI-1 are expressed in both the cumulus cells and the immature and in vitro matured oocytes. In addition, uPAR protein was localized by confocal microscopy in the plasma membrane of oocytes and cumulus cells of immature COCs. Results from this research led us to hypothesize that uPA/uPAR interaction could cause, over the oocyte and cumulus cells surfaces, a local production of plasmin mediated by uPA; plasmin formation could also be regulated by PAI-1. Keywords: uPAR; uPA; Oocytes; Cumulus Cells; Bovine