Sera from some patients with polymyositis-scleoderma overlap syndrome (PM-SCL) recognize two antigenically unrelated proteins, PMSCL1 and PMSCL2. Complete mouse Pmscl1 and Pmscl2 cDNA sequences, chromosomal localizations, exon/intron structure, and promoter region sequences of the mouse Pmscl2 gene are presented. The PMSCL1 gene was found to overlap significantly with cyclin A2 in both human and mouse. As such, it may be deduced that PMSCL1 sequences map to human chromosome 4q27 and the proximal portion of mouse chromosome (Chr) 3 where human and mouse cyclin A2 genes reside. Analysis of human and mouse PMSCL1 cDNA sequences provides evidence that the PMSCL1 protein is 68 amino acids longer than previously thought. A BAC containing mouse Pmscl2 was localized to distal mouse Chr 4 by FISH. This BAC contains the microsatellite D4Mit310. D4Mit310 colocalizes with a number of genes that map to human 1p36. In fact, a STS (G25404) located 54.6 cR from the top of human chromosome 1 was found to contain PMSCL2 sequence upon BLAST search.
Copyright 2000 Academic Press.