The zebrafish vitronectin receptor: Characterization of integrin αV and β3 expression patterns in early vertebrate development

Abstract

αVβ3 is a receptor for vitronectin and other extracellular matrix ligands, and it has been implicated in angiogenesis and osteoclast function in mammals. We have cloned full-length cDNAs of zebrafish integrin αV (itgαV), and two paralogous zebrafish β3 integrins (itgβ3.1 and itgβ3.2). Whole-mount in situ hybridization analysis revealed that αV and β3.1 share overlapping expression domains in apical ectodermal ridge, ventricular myocardium, hypothalamus, posterior tuberculum, medial tectal proliferation zone, and in the odontogenic field of the bilateral pharyngeal dentitions. In contrast to β3.1, β3.2 is transiently expressed throughout the developing embryo. In situ hybridization profiles and heterologous expression of proteins in tissue culture cells suggest that β3.1 is the major β3 paralog that associates with αV in zebrafish. Furthermore, when β3.1 expression profiles are compared to those of other potential αV partners (β1, β5, and β8), pharyngeal dentitions appear to represent a unique expression field for αV and β3.1. © 2007 Wiley-Liss, Inc.