Genomic organization, promoter, amino acid sequence, chromosomal localization, and expression of the human gene for CORS-26 (collagenous repeat-containing sequence of 26-kDa protein).

The murine gene for CORS-26 is located on mouse chromosome 15A2 and its expression has been reported to be restricted to fibroblasts, cartilage and kidney. Here, the complete genomic organization of the corresponding human CORS-26 gene with exon/intron boundaries and exon-specific primer combinations is presented. Additionally, a 1.2 kb fragment of the TATA box-containing promoter region was cloned and analyzed for putative transcription factor binding sites. The deduced amino acid sequence is presented completely. Northern blot analysis using a human multiple-tissue cDNA panel demonstrated expression of human CORS-26 mRNA in colon and small intestine. Additionally, RT-PCR analysis revealed expression of CORS-26 mRNA in placenta, fibroblasts and white adipose tissue. The chromosomal localization of the human CORS-26 gene was mapped to human chromosome 5p by fluorescence in situ hybridization (FISH). In humans, chromosomal imbalances on chromosome 5p were reported to be involved in the pathogenesis of osteosarcoma. Therefore, a human bone tumor cDNA panel was investigated and a strong CORS-26 mRNA expression was found in osteosarcoma, chondroblastoma and giant cell tumor. The present data provide the basis for further investigation of CORS-26 gene regulation in the context of mesenchymal tissue development and in the pathogenesis of bone or skeletal disease.