The binding between p67 and eukaryotic initiation factor 2 plays important roles in the protection of eIF2α from phosphorylation by kinases
Section snippets
Materials and methods
All chemicals used in this study were obtained from Sigma Chemicals (St. Louis, MO), Merck (Darmstadt, Germany), ICN Biomedicals, Inc. (Aurora, OH), Fisher Chemicals (Fairlawn, NJ), or Gibco-BRL (Rockville, MD). All enzymes used in this study were purchased from New England Biolabs (Beverly, MA). [35S]Methionine was purchased from Amersham Corporation.
Results and discussion
Previously, we reported that the D6/2 mutant has increased protection of eIF2α phosphorylation activity during normal growth conditions [8]. We measured its effect and the effects of five double mutants D6/2 + D251A, D6/2 + D262A, D6/2 + H331A, D6/2 + E364A, and D6/2 + E459A on the levels of eIF2α(P) and total eIF2α in serum-starved cells. The results were compared with the control cells expressing wild type p67 and EGFP alone (Fig. 1A and B). Results were normalized with the total eIF2α. Wild type p67
Acknowledgment
Kent State University Research Council supports this work.
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