Characterisation of mouse CD37: cDNA and genomic cloning.

The leukocyte surface antigen CD37 is a member of the transmembrane 4 superfamily (TM4SF) of glycoproteins which are predicted to span the lipid bilayer four times. The protein sequence and gene structure of mouse CD37 (Cd37) have been deduced through the isolation of cDNA and genomic clones. The Cd37 gene produces a major mRNA transcript of 1.2 kb that is restricted to cells of lymphoid and myeloid origin. Mouse CD37 is a glycoprotein of 281 amino acids in length, encoded by eight exons that span approximately 5.2 kb. CD37 is highly conserved between species, the mouse sequence sharing amino acid identities of 98% and 79% with rat and human, respectively. Cd37 shows a striking similarity in genomic organisation to other members of the TM4SF, which is consistent with the theory that this superfamily has evolved by gene duplication and divergence from a common ancestral gene.