MHC-2B gene: RNA and protein expression in bovine skeletal muscles

We have recently shown (Maccatrozzo et al., Eur Histochem J, in press) by means of combined RT-PCR and immunohistochemistry (monoclonal antibody BF-F3) that MHC-2B is not expressed in trunk and limb bovine muscles, whereas it is present in specialized eye muscles (rectus lateralis and retractor bulbi). MHC-1 or slow, MHC-2A, MHC-2X have been found to be expressed in all bovine muscles. In this study we examined MHC expression in bovine muscle fibres identifying mRNAs using RT-PCR and proteins using SDS-polyacrylamide gel electrophoresis in the same preparations. Single fibres dissected from diaphragm and longissimus and small bundles dissected from eye muscles were analysed. The comparison lead to the reliable identification of the electrophoretic bands corresponding to MHC isoforms and showed that in most cases there was a complete correspondence between mRNA and protein composition.