High hydrostatic pressure inhibits the biosynthesis of eukaryotic elongation factor-2.
2005 (English)In: Journal of Cellular Biochemistry, ISSN 0730-2312, E-ISSN 1097-4644, Vol. 94, no 3, 497-507 p., 15534876Article in journal (Refereed) Published
High continuous hydrostatic pressure is known to inhibit the total cellular protein synthesis. In this study, our goal was to identify pressure-regulated proteins by using two dimensional gel electrophoresis and mass spectrometry. This analysis showed that under 30 MPa continuous hydrostatic pressure the biosynthesis of eukaryotic elongation factor-2 (eEF-2) was inhibited both in HeLa carcinoma and T/C28a4 chondrocytic cell lines. Western blot analysis of HeLa cells revealed that the cellular protein level of eEF-2 decreased by 40%-50% within 12 h of the pressure treatment. However, the steady-state mRNA level of eEF-2 was not affected by the pressure. Cycloheximide addition after 4 h-pressure treatment suggested that the half-life of eEF-2 protein was shorter in pressurized cells. eEF-2 is responsible for the translocation of ribosome along the specific mRNA during translation, and its phosphorylation prevents the ribosomal translocation. Therefore, increased phosphorylation of eEF-2 was considered as one mechanism that could explain the reduced level of protein synthesis in pressurized HeLa cell cultures. However, Western blot analysis with an antibody recognizing the Thr56-phosphorylated form of eEF-2 showed that phosphorylation of eEF-2 was not elevated in pressurized samples. In conclusion, the inhibition of protein synthesis under high pressure occurs independent of the phosphorylation of eEF-2. However, this inhibition may result from the decrease of cellular eEF-2 protein.
Place, publisher, year, edition, pages
John Wiley & Sons, 2005. Vol. 94, no 3, 497-507 p., 15534876
Hydrostatic pressure, protein synthesis, eukaryotic elongation factor-2, two dimensional gel electrophoresis, mass spectrometry
Cell and Molecular Biology Biochemistry and Molecular Biology
Research subject Biochemistry; cellforskning
IdentifiersURN: urn:nbn:se:umu:diva-106661DOI: 10.1002/jcb.20333PubMedID: 15534876OAI: oai:DiVA.org:umu-106661DiVA: diva2:843264