RESUMEN
Protein synthesis was measured in the hearts of rats exposed to acetaldehyde vapour for 21 days. Exposure to acetaldehyde significantly increased heart weight (expressed as % body weight) but was without effect on the rate of synthesis of mixed cardiac proteins. Concentrations of RNA in the hearts were not altered by acetaldehyde exposure, indicating no change in RNA activity for protein synthesis.
Asunto(s)
Acetaldehído/farmacología , Corazón/efectos de los fármacos , Miocardio/metabolismo , Biosíntesis de Proteínas , Animales , Peso Corporal/efectos de los fármacos , Femenino , Corazón/anatomía & histología , Masculino , Tamaño de los Órganos/efectos de los fármacos , ARN/metabolismo , Ratas , Ratas Endogámicas , Factores SexualesRESUMEN
Myelin basic protein (MBP) from the Whaler shark (Carcharhinus obscurus) has been purified from acid extracts of a chloroform/methanol pellet from whole brains. The amino acid sequence of the majority of the protein has been determined and compared with the sequences of other MBPs. The shark protein has only 44% homology with the bovine protein, but, in common with other MBPs, it has basic residues distributed throughout the sequence and no extensive segments that are predicted to have an ordered secondary structure in solution. Shark MBP lacks the triproline sequence previously postulated to form a hairpin bend in the molecule. The region containing the putative consensus sequence for encephalitogenicity in the guinea pig contains several substitutions, thus accounting for the lack of activity of the shark protein. Studies of the secondary structure and self-association have shown that shark MBP possesses solution properties similar to those of the bovine protein, despite the extensive differences in primary structure.