Genomic construct and mapping of the gene for CMAP (leukocystatin/cystatinF, CST7) and identification of a proximal novel gene, BSCv (C20orf3)

It is proposed that CMAP (leukocystatin/cystatin F, HGMW-approved symbol CS T7) expression is correlated with the metastatic potential of malignant tum ors. FISH analysis of human and murine CMAP revealed the genomic loci 20p11 .21-p11.22 of the human family 2 cystatin cluster and mouse chromosome regi on 2G1-G3, respectively. Like murine CMAP, the human CMAP gene is construct ed from four divided exons, all of which encode the functional domains of t he putative translational product. Based on the computational analysis, a n ovel gene weakly similar to the plant strictosidine synthase, named BSCv (H GMW-approved symbol C20orf3), was identified on the opposite allele at a di stance of a few kilobases from the human CMAP gene. In between human CMAP a nd the BSCv gene, there is a unique tandem repeat sequence. CpG-rich island characteristics and GC-box features normally observed in housekeeping gene s were not seen around exon 1 of the CMPA gene, reflecting the restricted e xpression of CMAP in hematopoietic cells. (C) 2000 Academic Press.