Pannexin 1 Expression in Bovine Cumulus-Oocyte Complexes and Function During in vitro Maturation

Abstract

In this study we investigate the presence of pannexin 1 (PANX1) protein channels in bovine cumulus-oocyte complexes (COCs). Pannexin channels are a recently discovered family of proteins which have been characterized in other tissues and systems and found to be largely ubiquitously expressed. They have been shown to play a role in adenosine triphosphate (ATP) release, the removal of apoptotic cells, neurological functions, and inflammation. However, little is known about their potential roles in reproductive tissues. Here we investigate the expression of PANX1 in bovine cumulus-granulosa cells. We compare the expression in COCs from early versus late antral follicles and between oocytes with higher developmental competence to those with lower developmental competence. Furthermore, we characterize the potential role that PANX1 has during oocyte maturation and embryo development, following in vitro fertilization (IVF). We investigate oocyte maturation and developmental outcomes in vitro with PANX1 channel inhibition during in vitro maturation (IVM). We also look at possible functional roles that PANX1 inhibition may have on the maturing oocyte. Elucidating the role of PANX1 during oocyte maturation stands to further our understanding of the channel. With that knowledge, the foundation for manipulating the in vitro environment to improve bovine embryo production would be improved.