The subgroup C of the adenoviruses (Ad) and the group B coxsackieviruses (CVB) are structurally unrelated viruses that are known to compete for an unidentified
cell surface receptor. We now describe the isolation of cDNAs from human and mouse that encode the human CVB and Ad2 and 5 receptor (HCAR) and the mouse CVB Ad2 and 5 receptor (MCAR). Both are 46-kDa
glycoproteins whose primary amino acid sequences are highly homologous. Structurally, HCAR and MCAR appear to be transmembrane
proteins that contain two extracellular immunoglobulin-like domains and therefore belong to this superfamily. Transfection of either of these
cDNA molecules into receptor-negative NIH 3T3 cells conferred susceptibility to CVB
infection and permitted the expression of
beta-galactosidase from a recombinant Ad5 vector. In addition, HCAR and MCAR mRNAs could be detected on Northern blots of
oligo(dT)-selected
RNA from receptor-positive HeLa cells and TCMK-1 as well as several tissues of human and mouse origin that are known to be targets for Ad and CVB
infections. Finally, Western blots using
antibodies that inhibit virus binding to either the human or mouse CVB receptors detected 46-kDa
proteins in HCAR- and MCAR-transfected cells, respectively. Taken together, these results confirm that the isolated cDNAs encode the receptors for the subgroup C Ad and CVB.