Catalog # EP4391

eEF2K (Ser-78), phospho-specific Antibody

Rabbit Polyclonal

Application / Dilution

Size 100 μl

Species Reactivity Hu, Rt, Ms

MW 105 kDa



Eukaryotic elongation factor 2 (eEF2) catalyzes the translocation of peptidyl-tRNA from the A site to the P site on the ribosome. eEF2 kinase (eEF2K) phosphorylates and inactivates eEF2, resulting in the inhibition of peptide-chain elongation. eEF2K is normally dependent on Ca2+ ions and calmodulin, and can be activated by PKA in response to elevated cAMP levels during cell stress- or starvation-related conditions. Regulation of eEF2K occurs through phosphorylation at multiple sites. Ser-78 phosphorylation is required for calmodulin binding and eEF2K activity, while phosphorylation of Ser-500 is required for Ca2+/calmodulin-independent kinase activity. Thr-348 is an autophosphorylation site that is required for kinase activity. Inhibitory phosphorylation may also regulate eEF2K, since phosphorylation at Ser-359 by SAPK4/p38δ causes inactivation of eEF2K. Thus, multisite phospho-regulation of eEF2K may be important for proper control of eEF2K activity and protein translation.


Tavares, C.D. et al. (2012) Biochemistry. 51(11):2232.
Smith, E.M. & Proud, C.G. (2008) EMBO J. 27(7):1005.
Ryazanov, A.G. et al. (1997) Proc Natl Acad Sci. USA. 94:4884.

Western blot image of C2C12 treated with calyculin A (100 nM) for 30 min. (lanes 1 & 3), then the blot was treated with lambda phosphatase (lanes 2 & 4). The blot was probed with anti-eEF2K (N-terminus) at 1:500 (lanes 1 & 2) and anti-eEF2K (Ser-78) (EP4391) at 1:1000.

Phospho-eEF2K (Ser-78) synthetic peptide (coupled to carrier protein) corresponds to amino acids surrounding Ser-78 in human eEF2K. This sequence is well conserved in rat and mouse eEF2K, and has low homology to other proteins.

*For more information, see UniProt Accession O00418
Rabbit polyclonal, affinity-purified antibody is supplied in 100µl phosphate-buffered saline, 50% glycerol, 1 mg/ml BSA, and 0.05% sodium azide. Store at –20°C. Stable for 1 year.

The products are are safely shipped at ambient temperature for both domestic and international shipments. Each product is guaranteed to match the specifications as indicated on the corresponding technical data sheet. Please store at -20C upon arrival for long term storage.

The antibody was affinity purified using phospho-eEF2K (Ser-78) peptide (without carrier). This antibody detects a 105 kDa* protein corresponding to the molecular mass of eEF2K on SDS-PAGE immunoblots of mouse C2C12 and Jurkat cells treated with Calyculin A, and this reactivity is removed after lambda phosphatase treatment.

*All molecular weights (MW) are confirmed by comparison to Bio-Rad Rainbow Markers and to western blot mobilities of known proteins with similar MW.

This kit contains: