Identification of a novel collagen chain represented by extensive interruptions in the triple-helical region

We have isolated mouse cDNA clones that encode a newly discovered collagenous polypeptide. Four overlapping cDNA clones contained an open reading frame of 1140 amino acid residues of collagenous and non-collagenous domains. The predicted polypeptide consists of 10 collagenous domains of various length that are interrupted by 11 noncollagenous domains. The overall structural arrangement differed significantly from reported collagen chains of 17 different types. Northern-blot analyses showed hybridization of the cDNA to 5.6kb and 4.8kb mRNA species in liver and kidney that are due to utilization of the two poly (A) signals.