Cloning, sequencing and characterization of the 5'-flanking region of the human collagenase-3 gene

Collagenase-3 (matrix metalloprotease-13) is a recently discovered human collagenase produced in normal articular cartilage chondrocytes and thought to be involved in the pathological process of osteoarthritis. We have sequenced and characterized 1.6 kb of the human collagenase-3 gene 5'-flanking region. The transcription start site was located 22 bp upstream from the ATG start codon. Sequence analysis of the 5'-flanking region revealed the presence of the consensus recognition sites for the TATA and CCAAT DNA-binding proteins, activator protein-1 and E26 transformation specific/polyoma virus enhancer, as well as three core motifs of hormone response elements. Transient transfection assays demonstrated that a small fragment of 133 bp, containing the activator protein-1 and E26 transformation specific/polyoma virus enhancer sites promoted transcription in normal and osteoarthritic human chondrocytes with significantly higher activity than the original 1.6 kb fragment. Nucleotide sequence comparison of the promoter region of human collagenase-3 revealed a stronger similarity to the mouse collagenase-1 promoter than to the human collagenase-1 promoter.