Type XIV collagen is encoded by alternative transcripts with distinct 5′ regions and is a multidomain protein with homologies to von Willebrand's factor, fibronectin, and other matrix proteins

The combined nucleotide sequences of several overlapping cDNAs provide the first complete amino acid sequence of type XIV collagen. Independent confirmation of the deduced sequence is provided by amino acid sequencing of several tryptic peptides isolated from purified chicken skin type XIV collagen. Comparative analyses show that the amino-terminal non-triple-helical region of α1(XIV) chains contains sequence motifs that are similar to α1(IX) collagen, fibronectin type III repeats, and von Willebrand's factor A-domains. The results also strongly suggest that the α1(XIV) collagen gene is identical to the gene encoding the matrix component previously named undulin. cDNAs covering the 5′ region of α1(XIV) mRNA fall into two classes with distinct sequences in their 5′-untranslated regions. We believe the two alternative sequences result from differential splicing of the primary transcript. Interestingly, one of the untranslated sequences shows a high degree of identity with the cis-regulatory translational control sequence in the 5′-untranslated region of a Drosophila ribosomal protein mRNA. We hypothesize therefore that the sequence in α1(XIV) collagen may play a role in the control of α1(XIV) protein synthesis.