4E-BP1 antibody 4EBP1 antibody 4EBP1_HUMAN antibody BP 1 antibody eIF4E binding protein 1 antibody eIF4E-binding protein 1 antibody Eif4ebp1 antibody Eukaryotic translation initiation factor 4E-binding protein 1 antibody PHAS-I antibody PHASI antibody Phosphorylated heat- and acid-stable protein regulated by insulin 1 antibody
The multisubunit eukaryotic translation initiation factor (eIF) 4F recruits 40S ribosomal subunits to the 5 end of mRNA. The eIF4F subunit eIF4E interacts directly with the mRNA 5 cap structure. Assembly of the eIF4F complex is inhibited by a family of repressor polypeptides, the eIF4E-binding proteins (4E-BPs). 4E-BP1 (also known as PHAS-1) normally binds eIF4E, inhibiting cap-dependent translation. Hyper-phosphorylation of 4E-BP1 disrupts this binding, activating cap-dependent translation. The PI3-kinase/Akt pathway and the FRAP/mTOR kinase regulate 4E-BP1. 4E-BP1 is phosphorylated in vivo on multiple residues and phosphorylation by FRAP/mTOR on Threonine 37 and Threonine 46 of human 4E-BP1 may prime it for sub-sequent phosphorylation at sites including Serine 65 and Threonine 70. The corresponding rat residues include Threonine 36, Threonine 45, Serine 64 and Threonine 69. In vitro, 4E-BP1 is also phosphorylated by ataxia telangiectasia (ATM) at human Serine 112 (rat Serine 111) in response to an increase in insulin levels.
