Integrins and reproduction

Abstract

The integrins are adhesion molecules, located in the plasmatic membrane of all cells of the human organism, except in the eritrocites. They are responsible for many mechanisms of cellular function, as adhesion, orientation, migration, extracellular matrix organization, development and even the cellular growth, being present including in tumoral neoplasms cells. They are constituted by two chains of subunits α and β that relate each other through no covalents chemical ligations; eighteen subunits α and eight subunits β are known creating about for twenty four integrins heterodimers. The subunit a regulates the adhesion of ligants and the extracellular conformation, while the subunit β that has intracellular predomination, is associated the cytoskeleton proteins, with modulate inside to out and outside to in, with the genes expression, with proliferation, with migration and with cellular differentiation. The structures in which they attach are short sequences of aminoacids founds in many places of the cellular matrix. The most known sequence is the Arginine-Glycine-Aspartic Acid, but they the attach to other molecules like vitronectin, fibronectin ,laminin, actinin, collagen IV and others. Various mechanisms involved in the human reproduction process, beginning by follicular growth and development influenced by ovarians steroids culminating with ovulation; the fertilization , the blastocyst implantation in the endometrium , and the invasion and the embrionary growth, ask for a deep knowledge about the reproductive process. The aim for this work is to present a review about the integrins involvement with the complex process of the human reproduction. It points to its importance in researching the failures in the assisted reproductive techniques. Copyright - SBRA - Sociedade Brasileira de Reprodução Assistida.