Construction and partial characterization of two recombinant cDNA clones for procollagen from chicken cartilage.

Type II procollagen mRNA has been partially purified from embryonic chick sternal cartilage by guanidine hydrochloride extraction, sucrose gradient sedimentation and Sepharose 4B chromatography. Double stranded cDNA was synthesized using AMV reverse transcriptase and E. coli DNA polymerase I, tailed using terminal transferase and inserted into the Pst I site of pBR322. Two putative type II procollagen cDNA clones have been characterized. Both plasmids hybridize to 2 sternal RNA species, a major species of 5.3 kb and a minor species of 7 kb. These RNAs are present in total RNA from sterna and differentiated limb bud cultures but are not detected in RNA from stage 24 limb bud which has not yet differentiated to cartilage or in RNA from calvaria. The time of appearance of these RNAs during the differentiation of limb mesenchyme in culture parallels the appearance of translatable type II procollagen mRNA.