Expression of Type XVII Collagen α1 Chain mRNA in the Mouse Heart

Abstract

The type XVII collagen α1 chain has been identified as a component of the type I hemidesmosome, and is thus thought to play a role in extracellular matrix (ECM) maintenance and signal transduction between the cell and the ECM. We examined the expression of type XVII collagen α1 chain mRNA in the mouse heart by Northern blot analysis and determined the sequential changes of its expression in different developmental stages of the heart using the reverse transcriptase-polymerase chain reaction (RT-PCR) method. Northern blotting: Total RNA was extracted from 10 adult mouse hearts by the guanidine/cesium method. Hybridization was performed with mouse cDNA for α1 (XVII) collagen. RT-PCR: Total RNA was extracted from 7 embryos, 4 neonates and 8 adult mice. Reverse transcription was performed using oligo-dT primer and MMLV. Amplification was carried out in α1 (XVII) collagen and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). GAPDH served as an internal control. Northern blotting revealed a 5.6kb signal that was identical to that of the α1 (XVII) of skin and transformed keratinocyte reported previously. The sequences of the PCR products were also identical to those reported. The normalized expression ratios of α1 (XVII) were 0.91±0.20 in the embryonic heart, 0.36±0.20 in the neonatal heart and 0.96±0.21 in the adult heart. In conclusion, we identified the expression of type XVII collagen α1 chain mRNA in the mouse heart, suggesting that the type I hemidesmosome is located in the heart. The results of the RT-PCR at different developmental stages of the heart suggest that type XVII collagen contributes not only to cardiogenesis in the embryonic stage but also to maintenance of architecture and function in the adult heart.