First Author | Ruest LB | Year | 2002 |
Journal | J Biol Chem | Volume | 277 |
Issue | 7 | Pages | 5418-25 |
PubMed ID | 11724805 | Mgi Jnum | J:74607 |
Mgi Id | MGI:2158865 | Doi | 10.1074/jbc.M110685200 |
Citation | Ruest LB, et al. (2002) Peptide elongation factor eEF1A-2/S1 expression in cultured differentiated myotubes and its protective effect against caspase-3-mediated apoptosis. J Biol Chem 277(7):5418-25 |
abstractText | Peptide elongation factor eEF1A-2/S1, which shares 92% homology with eEF1A-1/EF-1alpha, is exclusively expressed in brain, heart, and skeletal muscle. In these tissues, eEF1A-2/S1 is the only type 1A elongation factor expressed in adulthood because a transition from eEF1A-1/EF-1alpha to eEF1A-2/S1 occurs in early postnatal development. In this article, we report that the expression of eEF1A-2/S1 protein is activated upon myogenic differentiation. Furthermore, we show that upon serum deprivation-induced apoptosis, eEF1A-2/S1 protein disappears and is replaced by its homolog eEF1A-1/EF-1alpha in dying myotubes; cell death is characterized by the activation of caspase-3. In addition, we show that the continuous expression of eEF1A-2/S1 resulting from adenoviral gene transfer protects differentiated myotubes from apoptosis by delaying their death, thus suggesting a prosurvival function for eEF1A-2/S1 in skeletal muscle. In contrast, myotube death is accelerated by the introduction of the homologous gene, eEF1A-1/EF-1alpha, whereas cells transfected with antisense eEF1A-1/EF-1alpha are protected from apoptosis. These results demonstrate that the two sister genes, eEF1A-1/EF-1alpha and eEF1A-2/S1, regulate myotube survival with the former exerting prodeath activity and the latter a prosurvival effect. |