title: Evidence for a second phosphorylation site on eIF-2 alpha from rabbit reticulocytes.
abstract: Ser 51 in the NH2-terminal sequence of the alpha-subunit of eukaryotic peptide initiation factor 2 (eIF-2) has been identified as a second phosphorylation site for the heme-controlled eIF-2 alpha kinase from rabbit reticulocytes. Increased phosphorylation of this serine relative to the previously described phosphorylation site (Ser 48) is observed when the kinase reaction is carried out in the presence of the alpha-subunit of spectrin. A synthetic peptide corresponding to eIF-2 alpha (41-54) is phosphorylated only in Ser 51 by the eIF-2 alpha kinase.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015852:Eukaryotic Initiation Factor-2; D010446:Peptide Fragments / Q000138:chemical synthesis; D010448:Peptide Initiation Factors / Q000032:analysis*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011506:Proteins / Q000032:analysis*; D011817:Rabbits; D012156:Reticulocytes / Q000032:analysis; D013049:Spectrin; D019892:eIF-2 Kinase
chemical_list: D015852:Eukaryotic Initiation Factor-2; D010446:Peptide Fragments; D010448:Peptide Initiation Factors; D011506:Proteins; D013049:Spectrin; D011494:Protein Kinases; D019892:eIF-2 Kinase