Open AccessIncreased phosphorylation of elongation factor 2 during mitosis in transformed human amnion cells correlates with a decreased rate of protein synthesis.
Author(s) -
Julio E. Celis,
Peder Madsen,
Alexey G. Ryazanov
Publication year - 1990
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.87.11.4231
Subject(s) - isoelectric focusing , mitosis , phosphorylation , biology , microbiology and biotechnology , elongation factor , protein biosynthesis , biochemistry , rna , ribosome , gene , enzyme
Elongation factor 2 was identified in the two-dimensional gel patterns of asynchronous human amnion cells (AMA) by comigration with purified rabbit reticulocyte elongation factor 2 and by two-dimensional gel immunoblot analysis using a specific rabbit polyclonal antibody. In all, four polypeptides were identified corresponding to isoelectric focusing polypeptides 2713 (95.0 kDa), 2714 (94.8 kDa), 3727 (94.8 kDa), and 3702 (93.6 kDa) (listed in order of decreasing pI values) in the computerized comprehensive two-dimensional gel data base of human AMA proteins. The relative proportion of two of these variants (isoelectric focusing polypeptides 3727 and 3702), which are phosphorylated, increased dramatically during mitosis. Since phosphorylation is known to render elongation factor 2 inactive in translation, this observation may partly explain the decline in the rate of protein synthesis observed during cell division.