Tissue-specific expression of type XIV collagen - A member of the FACIT class of collagens

The collagens represent a highly diverse superfamily of extracellular matrix proteins that can be divided into several distinct families. One of the families, called FACIT (fibril-associated collagens with interrupted triple-helices) family, contains molecules that appear to be associated with cross-striated fibrils composed of members of the fibrillar collagen family. We have determined a portion of the primary structure of a recently discovered member of the FACIT family, chicken α1(XIV) collagen, based on cloning and sequencing cDNAs. A synthetic oligopeptide from within the carboxy-terminal non-triple-helical domain of the α1(XIV) chain has been used for generating specific polyclonal antibodies. The antiserum, PS1, recognizes a 220 KDa polypeptide in immunoblots of extracts of chicken skin, tendons, and cartilage. Sequencing of a tryptic peptide generated from purified, immunoreactive material, gives a sequence identical to that derived from cDNA sequencing, providing strong support for the type XIV-specificity of PS1. We have examined the expression of type XIV collagen in developing chick embryos by immunostaining of sections from 12-day-old embryos with PS1 and by Northern blot analysis of RNA from several tissues from both 12- and 17-day-old embryos. The results show that type XIV collagen is prevalent within relatively dense connective tissues such as dermis, tendons, perichondrium, perimysium, the stroma of lungs and liver, and blood vessels.