4EBP1 (pT36/pT45) Alexa Fluor 647 (M31-16, Mouse) - Reactivity: Human, Mouse, Rat

The eukaryotic translation initiation factor 4E-Binding Protein 1 (4EBP1) is a phosphorylated heat- and acid-stable protein (PHAS-I or PHAS-1), and it is regulated by insulin. It is a member of the eIF4E-Binding Protein Family, which also includes the proteins 4EBP2 and 4EBP3. 4EBP1 binds with eukaryotic translation Initiation Factor 4E (eIF4E), which prevents its assembly into the eIF4E complex and inhibits cap-dependent translation. When 4EBP1 is phosphorylated, this binding is disrupted, allowing cap-dependent translation to be activated. Phosphorylation of 4EBP1 is required for protein synthesis, and it mediates the regulation of protein translation by stimuli that signal through the phosphoinositide 3 (PI3) kinase pathway.  We found that threonines 36 and 45 (T36/T45) are phosphorylated in resting human peripheral blood mononuclear cells. PI3 kinase inhibitors, such as LY294002 down-regulate the phosphorylation level of 4EBP1 (pT36/pT45).

The M31-16 monoclonal antibody recognizes the phosphorylated T36 and T45 of activated human 4EBP1.  The orthologous phosphorylation sites in mouse and rat 4EBP1 are T35 and T44.