Necessary for cellular interactions with laminin and the extracellular matrix. ; (Microbial infection) Receptor for the protective antigen (PA) of B.anthracis (PubMed:12700348, PubMed:15243628, PubMed:15326297). Binding of PA leads to heptamerization of the receptor-PA complex (PubMed:12700348, PubMed:15243628, PubMed:15326297). Upon binding of the PA of B.anthracis, the complex moves to glycosphingolipid-rich lipid rafts, where it is internalized via a clathrin-dependent pathway (PubMed:12551953, PubMed:15337774). In the endosomal membrane, at pH under 7, the complex then rearranges and forms a pore allowing the other components of anthrax toxin to escape to the cytoplasm (PubMed:12551953, PubMed:15337774).