Bovine sperm capacitation

In attempts to further understand the signal transduction cascades that regulate capacitation, our laboratory has recently correlated mouse, human, and bovine sperm capacitation with an increase in protein tyrosine phosphorylation of a variety of substrates (Visconti et ah, 1995a Carrera et ah, 1996 Galantino-Homer et ah, 1997). Many of these results have since been corroborated by other labs (Aitken et ah, 1995 Leclerc et ah, 1996 Luconi et ah, 1996 Emiliozzi and Fenichel, 1997). Using the mouse as an experimental paradigm, our laboratory has demonstrated... 

Galantino-Homer, H., Visconti, P.E., and Kopf, G.S. (1997). Regulation of protein tyrosine phosphorylation during bovine sperm capacitation by a cyclic adenosine 3, 5 -monophosphate-dependent pathway. Biol. Reprod. 56 707-719. 

Parrish, J.J., Susko-Parrish, J., Winer, M.A., and First, N.L. (1988). Capacitation of bovine sperm by heparin. Biol Reprod. 58 1171 -1180. 

Therien, I.. Soubeyrand, S.. and Manjunath, P. (1997), Major proteins of bovine seminal plasma modulate sperm capacitation by high-density lipoprotein. Biol. Reprod. 57 1080-1088. 

Uguz, C, Vredenburgh, W,L and Parrish, J.J. (1994). Heparin-induced capacitation but not intracellular alkalinization of bovine sperm is inhibited by Rp-adenosine-3, 5 -cyclic monophosphothioate. Biol. Reprod. 57 1031-1039. 

Vredenburgh-Wilberg, W.L. and Parrish, J.J. (1995). Intracellular pH of bovine sperm increases during capacitation. Mol. Reprod. Dev. 40 490-502. 

Anderson SH, Killian GJ. 1994. Effect of macromolecules from oviductal conditioned medium on bovine sperm motion and capacitation. Biol Reprod 51 759-799. 

The mechanism by which albumin (in many cases bovine serum albumin BSA) promotes capacitation in mammalian sperm is intriguing as it is believed to function during capacitation in vitro as a sink for the removal of cholesterol from the sperm plasma membrane (Go and Wolf, 1985 Langlais and Roberts, 1998 Cross, 1998). The association between cholesterol removal from the sperm plasma membrane, albumin, and capacitation was first proposed by Davis and colleagues (1980). Removal of this sterol likely accounts for the membrane fluidity changes observed during capacitation (Wolf et al., 1986). The consequence of the removal of this sterol is that the cholesterol to phospholipid ratio in the membrane decreases, and such changes in... 

---