ABfinity™ Recombinant Rabbit Monoclonal Antibody validated to Human and expected reactivity with human, mouse, rat, equine, opossum, bovine, and zebrafish. This antibody is validated for use in Western Blot, Immunohistochemistry, Immunofluorescence, Flow Cytometry, and Immunoassay (ELISA). 4E-BP1 [pT37] is encoded by the 1978 gene, also known as Eukaryotic translation initiation factor 4E binding protein 1, BP-1, 4EBP1, 4E-BP1, PHAS-I, MGC4316, EIF4EBP1.

Eukaryotic initiation factor 4E binding protein 1 (4E-BP1), also known as PHAS, is a ~20 kDa member of a family of eIF4E-binding proteins whose binding affinity to eIF4E is regulated by its phosphorylation. It inhibits cap-dependent translation by binding to eIF4E on the same site that overlaps the binding site for eIF4G, preventing its binding to the latter and eventually leading to an increase in mRNA translation. The phosphorylatin of 4E-BP1 is critical in determining cell fate by controlling translation initiation and apoptotic potency. 4E-BP1 is hyperphosphorylated in response to several external stimuli including hormones, growth factors, mitogens, cytokines and G-protein–coupled receptors and in response to stress conditions including nutrient deprivation. The phosphorylation of 4E-BP1 increases in response to activated phosphoinositol 3’-kinase (PI-3K) or its downstream effector Akt⁄PKB. 4E-BP1 is believed to mediate PI-3K and FRAP⁄mTOR signaling and is phosphorylated on at least six serine and threonine sites (Thr 37, Thr 46, Ser 65, Thr 70, Ser 83, and Ser 112). The phosphorylation of these sites is believed to occur in an orderly fashion where phosphorylation of threonine 37 and 46 by FRAP⁄mTOR is a priming step for subsequent phosphorylation of 4E-BP1 at the carboxy-terminal sites.

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