CLONING OF MOUSE TYPE-XV COLLAGEN SEQUENCES AND MAPPING OF THE CORRESPONDING GENE TO 4B1-3 - COMPARISON OF MOUSE AND HUMAN ALPHA-1(XV) COLLAGEN SEQUENCES INDICATES DIVERGENCE IN THE NUMBER OF SMALL COLLAGENOUSDOMAINS

We report on full-length mouse type XV collagen cDNAs that encode a 13 67-residue alpha 1(XV) chain. The amino acid sequences of the mouse an d previously characterized human alpha 1(XV) chains exhibit an overall identity of 72%. The highest homology between these chains and to the structurally related type XVIII collagen is observed in their C-termi nal noncollagenous domains. Although the mouse and human alpha 1(XV) c hains are highly homologous and similar in their overall domain struct ure, the mouse chain contains only seven collagenous domains, whereas the human chain contains nine. Northern analysis of several mouse tiss ues indicated strong hybridization in the case of heart and skeletal m uscle RNAs and moderate signals with kidney, lung, and testis RNAs. An alysis of type XV collagen mRNA levels at different stages of mouse em bryonic development indicated a marked increase in the level between 1 1 and 15 days of development, which coincides with pronounced developm ent of the muscles, heart, and vascular system in the mouse embryo, Th e mouse gene for type XV collagen was mapped by fluorescence in situ h ybridization to chromosome 4, band B1-3. This result indicates that th e mouse type XV collagen gene and its human counterpart are located in the chromosomal segments with conserved syntenies. (C) 1997 Academic Press.