Sequence analysis of type VI collagen subunits in cardiomyopathic hamster hearts

Abstract

At the AALAS 2009 meeting, we reported an accumulation of collagen type VI (COL6) in the hearts of cardiomyopathic hamsters (J2N‐k) in comparison with normal controls (J2N‐n). In this study, we determined the cDNA sequences of three subunits of COL6 in the cardiomyopathic hearts of J2N‐k hamsters using a SMARTer RACE cDNA amplification kit (Clontech) with total RNA extracted from a 6‐month‐old J2N‐k male hamster heart and subsequent direct sequencing of the PCR products. Primers were designed from the corresponding mouse and rat sequences. The sequences have been deposited in DDBJ with the accession numbers AB529512, AB529513, and AB530134 for COL6A1, COL6A2, and COL6A3, respectively. NCBI conserved domain searches indicated that all three subunits contained the same vWFA domain structures as their mouse counterparts. In particular, hamster heart COL6A3 lacks three domains in the N‐terminus, as in normal mouse and human hearts. These results suggest that the accumulation of COL6 in J2N‐k hearts is caused by altered expression and/or degradation of COL6, not by its structural abnormality. This work was supported by a grant from the Ministry of Health, Labor, and Welfare of Japan.