CLONING AND SEQUENCING OF MOUSE VCAM-1 CDNA

We report here the nucleotide sequence of a cDNA encoding the mouse vascular cell adhesion molecule-1 (VCAM-1), a member of the immunoglobulin gene superfamily. The 2972-bp cDNA encodes 739 amino acids (aa) and shows 76.4% and 75.9% similarity with the human VCAM-1 nucleotide (nt) and aa sequence, respectively. Three independent cDNA clones had a 7-Ig unit structure (molecule containing a seven 'immunoglobulin motif' repeat), and only sequences corresponding to the 7- (and not to the 6)-Ig unit VCAM were detected by reverse transcription polymerase chain reaction (RT-PCR), indicating that in the mouse this is the dominant, if not exclusive, form of this molecule. Unlike other adhesion molecules, the cytoplasmic tails (19 aa) of mouse and human VCAM-1 are identical, despite a 85.2% similarity only at the nt level, suggesting a critical functional role.