Gene structure, chromosomal location, and basis for alternative mRNA splicing of the human VCAM1 gene

Vascular cell adhesion molecule 1 (VCAM-1) is a cell surface glycoprotein adhesive for certain blood leukocytes and tumor cells, which is expressed by activated endothelium in a variety of pathologic conditions including atherosclerosis. Genomic clones encoding the VCAM1 gene were isolated and the organization of the gene was determined. The gene, which is present in a single copy in the human genome, contains 9 exons spanning approximately 25 kilobases of DNA. Exons 2-8 contain C2 or H-type immunoglobulin domains. At least two different VCAM-1 precursors can be generated from the human gene as a result of alternative mRNA splicing events, which include or exclude exon 5. A consensus TATAA element is located upstream of the transcriptional start site. The VCAM1 promoter contains consensus binding sites for NF-kappa B, the GATA family of transcription factors, as well as an AP1 site. The VCAM1 gene was assigned to the 1p31-32 region of chromosome 1 based on the analysis of human-mouse hybrid cell lines and in situ hybridization. Structural analysis of the human VCAM1 gene provides the basis for alternative mRNA splicing and an initial approach to elucidating the regulation of VCAM-1 expression.