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Download Product Insert (PDF) PRODUCT INFORMATION eIF4E (human recombinant) Item No. 15137 Overview and Properties Synonyms: eIF-4F 25 kDa subunit, Eukaryotic Translation Initiation Factor 4E, mRNA Cap-binding Protein Source: Recombinant protein expressed in E. coli Amino Acids: 2-217 (full length) Uniprot No.: P06730 Molecular Weight: 25.2 kDa Storage: -80°C (as supplied) Stability: ≥1 year Purity: batch specific (≥55% estimated by SDS-PAGE) Supplied in: 20 mM HEPES, pH 7.5, containing 100 mM potassium chloride, 2 mM DTT, and 10% glycerol Protein Concentration: batch specific mg/ml Image 1 2 3 4 250 kDa · · · · · · · 150 kDa · · · · · · · 100 kDa · · · · · · · 75 kDa · · · · · · · 50 kDa · · · · · · · 37 kDa · · · · · · · 25 kDa · · · · · · · 20 kDa · · · · · · · 15 kDa · · · · · · · Lane 1: MW Markers Lane 2: eIF4E (human recombinant) (4 µg) Lane 3: eIF4E (human recombinant) (2 µg) Lane 4: eIF4E (human recombinant) (1 µg) Representaõve gel image shown; actual purity may vary between each batch. WARNING CAYMAN CHEMICAL THIS PRODUCT IS FOR RESEARCH ONLY - NOT FOR HUMAN OR VETERINARY DIAGNOSTIC OR THERAPEUTIC USE. 1180 EAST ELLSWORTH RD SAFETY DATA ANN ARBOR, MI 48108 · USA This material should be considered hazardous until further information becomes available. Do not ingest, inhale, get in eyes, on skin, or on clothing. Wash thoroughly after handling. Before use, the user must review the complete Safety Data Sheet, which has been sent via email to your institution. PHONE: [800] 364-9897 WARRANTY AND LIMITATION OF REMEDY [734] 971-3335 Buyer agrees to purchase the material subject to Cayman’s Terms and Conditions. Complete Terms and Conditions including Warranty and Limitation of Liability information can be found on our website. FAX: [734] 971-3640 [email protected] Copyright Cayman Chemical Company, 06/17/2021 WWW.CAYMANCHEM.COM PRODUCT INFORMATION Description Eukaryotic translation is a complex biochemical process requiring several initiation factors. The first step in the initiation of mRNA translation involves binding of the small ribosomal subunit to mRNA.1 The central component in the recruitment of the pre-initiation complex during translation is the eukaryotic initiation factor 4F (eIF4F) complex, composed of eIF4A, eIF4E, and eIF4G1/eIF4G3.2 The 5’-terminal end of eukaryotic mRNA has a common cap structure that is important for stabilizing mRNA and ribosome binding.3 The eIF4E component binds specifically to the mRNA cap structure to initiate protein synthesis by recognizing methyl-7-guanosine.2,4 eIFA is a DEAD-box helicase, responsible for unwinding the mRNA, while eIF4G acts as a scaffold protein with binding sites for the poly(A)-binding protein and eIF3. eIF4G also possesses central and C-terminal eIF4A binding sites and a C-terminal binding site for the protein kinase Mnk1 (mitogen-activated protein kinase-interacting kinase).5 Mnk1 phosphorylates eIF4E at Ser209, which is believed to be essential for eIF4E’s oncogenic potential.6-8 Further, overexpression of eIF4e is seen in many human malignancies, including breast, colon, head and neck carcinomas, and others.9-10 References 1. Tomoo, K., Shen, X., Okabe, K., et al. Crystal structures of 7-methylguanosine 5’-triphosphate (m7GTP)- and P1-7-methylguanosine-P3-adenosine-5’,5’-triphosphate (m7GpppA)-bound human full-length eukaryotic initiation factor 4E: Biological importance of the C-terminal flexible region. Biochem. J. 362(pt 3), 539-544 (2002). 2. Marcotrigiano, J., Gingras, A.C., Sonenberg, N., et al. Cocrystal structure of the messenger RNA 5’ cap-binding protein (eIF4E) bound to 7-methyl-GDP. Cell 89(6), 951-961 (1997). 3. Morino, S., Hazama, H., Ozaki, M., et al. Analysis of the mRNA cap-binding ability of human eukaryotic initiation factor-4E by use of recombinant wild-type and mutant forms. Eur. J. Biochem. 239(3), 597-601 (1996). 4. Haghighat, A. and Sonenberg, N. eIF4G dramatically enhances the binding of eIF4E to the mRNA 5’-cap structure. J. Biol. Chem. 272(35), 21677-21680 (1997). 5. Schütz, P., Bumann, M., Oberholzer, A.E., et al. Crystal structure of the yeast eIF4A-eIF4G complex: An RNA-helicase controlled by protein-protein interactions. Proc. Natl. Acad. Sci. USA 105(28), 9564-9569 (2008). 6. Shveygert, M., Kaiser, C., Bradrick, S.S., et al. Regulation of eukaryotic initiation factor 4E (eIF4E) phosphorylation by mitogen-activated protein kinase occurs through modulation of Mnk1-eIF4G interaction. Mol. Cell Biol. 30(21), 5160-5167 (2010). 7. Silva, R.L. and Wendel, H.G. MNK, EIF4E and targeting translation for therapy. Cell Cycle 7(5), 553-555 (2008). 8. Furic, L., Rong, L., Larsson, O., et al. eIF4E phosphorylation promotes tumorigenesis and is associated with prostate cancer progression. Proc. Natl. Acad. Sci. USA 107(32), 14134-14139 (2010). 9. Carroll, M. and Borden, K.L. The oncogene eIF4E: Using biochemical insights to target cancer. J. Interferon Cytokine Res. 33(5), 227-238 (2013). 10. Yin, X., Kim, R.H., Sun, G., et al. Overexpression of eukaryotic initiation factor 4E is correlated with increased risk for systemic dissemination in node-positive breast cancer patients. J. Am. Coll. Surg. (2014). CAYMAN CHEMICAL 1180 EAST ELLSWORTH RD ANN ARBOR, MI 48108 · USA PHONE: [800] 364-9897 [734] 971-3335 FAX: [734] 971-3640 [email protected] WWW.CAYMANCHEM.COM.
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