Specific integrin subunits in bovine oocytes, including novel sequences for alpha 6 and beta 3 subunits

Abstract

Integrins facilitate attachment of cells to the extra-cellular matrix, often binding the arginine-glycine-aspartic acid tri-peptide motif, thus facilitating cell migration, mediating cell-cell adhesion, linking the extracellular matrix (ECM) with cytoskeletal elements, and acting as signaling molecules. Adhesion activates signaling mechanisms that regulate integrin function, cytoskeletal assembly, cell behavior, and protein synthesis. Immunofluorescence was used to determine the presence of integrin alpha and beta subunits on the surface of bovine oocytes using a panel of monoclonal antibodies (mAbs) specific for alphaL, alphaM, alphaX, alphaV, alpha2, alpha4, alpha6, beta1, beta2, and beta3 antigens, with multiple antibodies for each subunit. Confocal microscopy indicated the presence of alphaV, alpha6, alpha4, alpha2, ss1, and ss3 integrin subunits on the plasma membrane of bovine oocytes. The presence of these subunits was verified by RT-PCR analysis using primers designed based on known gene sequences of bovine integrin subunits, or by using sequence information using bovine expressed sequence tags (EST) compared with known human and murine integrin subunit gene sequence information. Previously unpublished sequence information for bovine alpha6 and beta3 integrins was determined. The presence of these integrin subunits on the bovine oocyte vitelline membrane supports the hypothesis that sperm-oocyte interactions in the bovine are mediated by integrins.

The integrin-binding motif RGDS induces protein tyrosine phosphorylation without activation in Bufo arenarum (Amphibia) oocytes

“…different glycosylation patterns). The a5 subunit has been detected in the oocyte PM of different mammals such as mice, cows and humans (Evans et al 1995, Sengoku et al 2004, Pate et al 2007, and in X. laevis oocytes (Joos et al 1995). We also found that the aV integrin subunit is expressed by B. arenarum oocytes.…”

Identification of Selection Signatures in Cattle Breeds Selected for Dairy Production

“…Both ITGB3 (integrin, beta 3) and ITFG1, (integrin alpha FG-GAP repeat containing 1) are expressed in the mammary gland (Lemay et al 2009). Subunits of ITGB3 have been identified on the bovine oocyte vitelline membrane (Pate et al 2007) and have been reported to be involved in receptors for foot-and-mouth disease (Duque et al 2004).…”

Reduction of Mouse Egg Surface Integrin Alpha9 Subunit (ITGA9) Reduces the Egg's Ability to Support Sperm-Egg Binding and Fusion1

“…To detect egg-associated AP activity, individual eggs were transferred to 25 ll of AP assay buffer (20 mM Tris-HCl, pH 9.5, 1 mM MgCl 2 ) in a 12 3 75-mm polystyrene tube. One hundred microliters of enhancer-substrate solution (AP assay buffer containing 25 …”

“…Members of the integrin family of heterodimeric cell adhesion molecules are another group of egg candidate molecules. Mammalian eggs express at least three integrin b subunits and seven a subunits, with a few differences between species [13][14][15][16][17][18][19][20][21][22][23][24][25]. Egg integrins have been suggested to participate in gamete interactions based on inhibition of sperm-egg interactions in IVF assays using antibodies to specific integrin subunits or peptides blocking specific subfamilies of integrins [18,21,23,24,[26][27][28][29].…”