Phospho-eIF4EBP1-T45 Rabbit pAb for Western Blot - Q13541

Core Product Specifications and Parameters

Biological Background: eIF4EBP1 Function and Localization

• Eukaryotic translation initiation factor 4E-binding protein 1 (eIF4EBP1, also known as PHAS-I) is a key repressor of cap-dependent translation initiation. It belongs to the eIF4E-binding protein family and competes with eIF4G for binding to eIF4E, thereby preventing assembly of the eIF4F complex.
• The repressor activity of eIF4EBP1 is regulated by its phosphorylation status: hypophosphorylated eIF4EBP1 binds eIF4E strongly and inhibits translation, whereas hyperphosphorylation (e.g., at Thr45 and other sites) dissociates it from eIF4E, allowing eIF4F formation and translation initiation.
• eIF4EBP1 mediates the regulation of protein synthesis downstream of various stimuli, including hormones, growth factors, and nutrients, through the MAP kinase and mTORC1 signaling pathways. Phosphorylation at Thr45 is a critical early event in the sequential multi-site phosphorylation cascade.
• Subcellular localization is predominantly cytoplasmic, but eIF4EBP1 can also shuttle into the nucleus, where it may have additional regulatory roles.
• Post-translational modifications include acetylation, ubiquitination (isopeptide bond formation), and extensive phosphorylation at multiple residues. The calculated molecular weight of the unmodified protein is approximately 12.5 kDa, with migration on SDS-PAGE often observed around 13–15 kDa depending on phosphorylation state.
• eIF4EBP1 is widely expressed and plays a central role in controlling cell growth, proliferation, and survival. Dysregulation of its phosphorylation is implicated in cancer and metabolic disorders.

Experimental Guidance and Technical Tips

• The immunogen used is a synthetic phospho-peptide spanning Thr45, indicating that this antibody is designed to specifically recognize the phosphorylated Thr45 form of eIF4EBP1. Cross-reactivity with unphosphorylated eIF4EBP1 or other family members is unlikely but should be assessed in relevant model systems.
• For Western blotting, ensure that protein lysates are prepared in the presence of phosphatase inhibitors to preserve the phosphorylation state. A band at approximately 13–15 kDa is expected for human eIF4EBP1; the apparent molecular weight may shift slightly depending on overall phosphorylation levels.
• Include appropriate controls to validate antibody specificity, such as untreated versus phosphatase-treated lysates, or lysates from cells with modulated mTORC1 activity (e.g., serum starvation/insulin stimulation).
• The antibody’s performance in other applications (e.g., IHC, IF, IP) has not been described; preliminary testing is recommended if used outside of WB.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio specializes in empowering diagnostic manufacturers and research institutions with a comprehensive portfolio of IVD raw materials. This anti-phospho-eIF4EBP1 antibody supports research in translational control and mTOR signaling, areas critical for oncology and metabolic disease diagnostics. As your integrated sourcing partner, CamelBio offers validated antibody pairs, optimized monoclonal/polyclonal antibodies, bulk ancillary reagents, and flexible access to rare-target raw materials—streamlining your workflow from concept to clinic.