Integrins in the Ovary

ABSTRACT

Integrins are the major receptors mediating adhesion to the extracellular matrix. Following ligand binding, conformational changes of integrins induce the recruitment of multiple signaling and scaffolding proteins that connect integrin tails to the actin cytoskeleton and permit activation of signaling pathways regulating cell proliferation, apoptosis, differentiation, and migration. In the ovary, extracellular matrix components present in the follicular basement membrane, around follicular cells, and in the follicular fluid participate in the regulation of follicular development, and a role of integrins in this process is strongly suggested. We discuss available data on integrin expression in ovary, integrin function in granulosa cells, and the possible involvement of integrins in follicular growth, atresia, and luteinization. We also discuss the potential role of oocyte integrins as receptors for sperm ADAMs (a disintegrin and metalloproteinase) in fertilization and the cooperation of integrins with proteinases in regulating proliferation, adhesion, migration, and invasion of ovarian surface epithelium cells in ovarian tumor development.

KEYWORDS

Integrin signaling - ovarian follicles - oocyte - fertilization - cancer

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