MHV-resistant SJL/J mice express a non-functional homolog to the MHV receptor glycoprotein

MHV-A59 recognizes a 100-110 K glycoprotein receptor on intestinal and liver plasma membranes. The receptor protein was affinity purified using an anti-receptor monoclonal antibody. Purified receptor was sequenced from the 1st to the 15th amino acids. Antiserum raised against a synthetic peptide having this sequence bound to the 110 K receptor from BALB/c intestine and a 58 K fragment of the receptor. SJL/J mice are resistant to MHV-A59 and their plasma membranes were previously shown to lack binding to MHV. However, anti-peptide antibody bound to a 105 K protein and a 53 K protein fragment from SJL/J plasma membranes. These SJL/J proteins did not bind MHV or to the blocking monoclonal anti-receptor antibody. Genetic resistance of SJL/J mice to MHV-A59 appears to be due to mutation of the receptor glycoprotein resulting in a molecule that does not bind MHV.