Cre-loxP–mediated Inactivation of the α6A Integrin Splice Variant In Vivo: Evidence for a Specific Functional Role of α6A in Lymphocyte Migration but Not in Heart Development

摘要: Two splice variants of the α6 integrin subunit, α6A and α6B, with different cytoplasmic domains, have previously been described. While α6B is expressed throughout development mouse, expression begins at 8.5 days post coitum initially restricted to myocardium. Later in ontogeny, found various epithelia certain cells immune system. In this study, we investigated function vivo by generating knockout mice deficient for variant. The Cre- loxP system bacteriophage P1 was used specifically remove exon encoding domain embryonic stem cells, deletion resulted all tissues that normally express α6A. We show α6A−/− develop are fertile. substitution does not impair heart, hemidesmosome formation epidermis, or keratinocyte migration. Furthermore, T differentiated mice. However, leads a decrease migration lymphocytes through laminin-coated Transwell filters reduction number isolated from peripheral mesenteric lymph nodes. Lymphocyte homing nodes, which involves types integrin–ligand interactions, affected mice, indicating reduced node could be directly attributed defects lymphocyte trafficking. Nevertheless, might necessary optimal on laminin pathological conditions.