Expression pattern of αvβ3 and αvβ5 integrin mRNA in mouse fetal gonads

The alpha v beta 3 and alpha v beta 5 integrins are known as transmembrane receptors capable of binding to the RGD amino acid peptide sequence. In mouse early gonadogenesis, some proteins containing the RGD sequence are deposited into extracellular space and participate in morphogenesis. We analyzed the expression patterns of the alpha V beta 3 and alpha v beta 5 integrins in mouse developing gonads (10.5-13.5 days post coitum) using whole-mount in situ hybridization. The alpha v integrin mRNA was homogenously expressed in developing gonadal regions. On the other hand, the beta 3 integrin mRNA was found only in large and round cells (presumptive germ cells), whereas beta 5 integrin was localized in gonadal somatic cells, with the exception of coelomic epithelial cells. The beta 3 integrin-expressed cells were determined to be primordial germ cells because the number of these cells was drastically reduced in busulfan-treated gonads. In this study, we demonstrated that the alpha v beta 3 and alpha v beta 5 integrins are widely localized in the mouse developing gonads and discussed their presumptive functions on mouse gonadogenesis.