Product: Phospho-4E-BP1 (Thr45) Antibody
Catalog: AF3432
Description: Rabbit polyclonal antibody to Phospho-4E-BP1 (Thr45)
Application: WB IHC IF/ICC
Reactivity: Human, Mouse, Rat
Prediction: Pig, Zebrafish, Bovine, Horse, Sheep, Rabbit, Dog, Chicken
Mol.Wt.: 18kDa; 13kD(Calculated).
Uniprot: Q13541
RRID: AB_2834874

View similar products>>

   Size Price Inventory
 100ul $280 In stock
 200ul $350 In stock

Lead Time: Same day delivery

For pricing and ordering contact:
Local distributors

Product Info

WB 1:500-1:2000, IHC 1:50-1:200, IF/ICC 1:100-1:500
*The optimal dilutions should be determined by the end user.

WB: For western blot detection of denatured protein samples. IHC: For immunohistochemical detection of paraffin sections (IHC-p) or frozen sections (IHC-f) of tissue samples. IF/ICC: For immunofluorescence detection of cell samples. ELISA(peptide): For ELISA detection of antigenic peptide.

Pig(100%), Zebrafish(100%), Bovine(100%), Horse(100%), Sheep(100%), Rabbit(100%), Dog(100%), Chicken(82%)
Phospho-4E-BP1 (Thr45) Antibody detects endogenous levels of 4E-BP1 only when phosphorylated at Threonine 45.
Cite Format: Affinity Biosciences Cat# AF3432, RRID:AB_2834874.
The antibody is from purified rabbit serum by affinity purification via sequential chromatography on phospho-peptide and non-phospho-peptide affinity columns.
Rabbit IgG in phosphate buffered saline , pH 7.4, 150mM NaCl, 0.02% sodium azide and 50% glycerol. Store at -20 °C. Stable for 12 months from date of receipt.


4E-BP1; 4EBP1; 4EBP1_HUMAN; BP 1; eIF4E binding protein 1; eIF4E-binding protein 1; Eif4ebp1; Eukaryotic translation initiation factor 4E-binding protein 1; PHAS-I; PHASI; Phosphorylated heat- and acid-stable protein regulated by insulin 1;


4E-BP1 binds to eIF4E, preventing its assembly into the EIF4F complex and inhibiting cap-dependent translation. Phosphorylation of 4E-BP1 disrupts this binding, activating cap-dependent translation.



Score>80(red) has high confidence and is suggested to be used for WB detection. *The prediction model is mainly based on the alignment of immunogen sequences, the results are for reference only, not as the basis of quality assurance.

Model Confidence:
High(score>80) Medium(80>score>50) Low(score<50) No confidence

PTMs - Q13541 As Substrate

Site PTM Type Enzyme
S2 Acetylation
S2 Phosphorylation
S5 Phosphorylation
S6 Phosphorylation
S8 Phosphorylation Q13315 (ATM)
T10 Phosphorylation
S12 Phosphorylation
Y34 Phosphorylation
S35 Phosphorylation
T36 Phosphorylation P51449 (RORC) , O75582 (RPS6KA5) , P31751 (AKT2) , P42345 (MTOR)
T37 Phosphorylation P49841 (GSK3B) , Q16539 (MAPK14) , P31749 (AKT1) , P42345 (MTOR) , P06493 (CDK1) , P28482 (MAPK1) , Q5S007 (LRRK2)
T41 Phosphorylation P42345 (MTOR) , P49674 (CSNK1E)
S44 Phosphorylation P42345 (MTOR)
T45 Phosphorylation O75582 (RPS6KA5) , P28482 (MAPK1) , P42345 (MTOR) , P31751 (AKT2) , P51449 (RORC)
T46 Phosphorylation P06493 (CDK1) , Q5S007 (LRRK2) , Q16539 (MAPK14) , P42345 (MTOR) , P31749 (AKT1) , P28482 (MAPK1) , P49841 (GSK3B)
T50 Phosphorylation P49674 (CSNK1E)
Y54 Phosphorylation
K57 Ubiquitination
C62 S-Nitrosylation
R63 Methylation
S65 Phosphorylation P27361 (MAPK3) , P42345 (MTOR) , P28482 (MAPK1) , O75582 (RPS6KA5) , Q8TAI7 (RHEBL1) , P31749 (AKT1) , Q92630 (DYRK2) , Q9P1W9 (PIM2) , P06493 (CDK1) , Q16539 (MAPK14)
T68 Phosphorylation
K69 Ubiquitination
T70 Phosphorylation P28482 (MAPK1) , P06493 (CDK1) , Q16539 (MAPK14) , P42345 (MTOR) , P41279 (MAP3K8)
T77 Phosphorylation
T82 Phosphorylation
S83 Phosphorylation P42345 (MTOR) , P06493 (CDK1) , P28482 (MAPK1)
S85 Phosphorylation
S86 Phosphorylation
S94 Phosphorylation Q13315 (ATM) , Q13535 (ATR)
S96 Phosphorylation
S101 Phosphorylation Q92630 (DYRK2) , P42345 (MTOR)
S112 Phosphorylation P19784 (CSNK2A2) , P68400 (CSNK2A1) , Q13315 (ATM)

Research Backgrounds


Repressor of translation initiation that regulates EIF4E activity by preventing its assembly into the eIF4F complex: hypophosphorylated form competes with EIF4G1/EIF4G3 and strongly binds to EIF4E, leading to repress translation. In contrast, hyperphosphorylated form dissociates from EIF4E, allowing interaction between EIF4G1/EIF4G3 and EIF4E, leading to initiation of translation. Mediates the regulation of protein translation by hormones, growth factors and other stimuli that signal through the MAP kinase and mTORC1 pathways.


Phosphorylated on serine and threonine residues in response to insulin, EGF and PDGF. Phosphorylation at Thr-37, Thr-46, Ser-65 and Thr-70, corresponding to the hyperphosphorylated form, is regulated by mTORC1 and abolishes binding to EIF4E.

Ubiquitinated: when eIF4E levels are low, hypophosphorylated form is ubiquitinated by the BCR(KLHL25) complex, leading to its degradation and serving as a homeostatic mechanism to maintain translation and prevent eIF4E inhibition when eIF4E levels are low. Not ubiquitinated when hyperphosphorylated (at Thr-37, Thr-46, Ser-65 and Thr-70) or associated with eIF4E.

Subunit Structure:

Hypophosphorylated EIF4EBP1 competes with EIF4G1/EIF4G3 to interact with EIF4E; insulin stimulated MAP-kinase (MAPK1 and MAPK3) or mTORC1 phosphorylation of EIF4EBP1 causes dissociation of the complex allowing EIF4G1/EIF4G3 to bind and consequent initiation of translation. Interacts (via TOS motif) with RPTOR; promoting phosphorylation by mTORC1.


The TOS motif mediates interaction with RPTOR, leading to promote phosphorylation by mTORC1 complex.

Belongs to the eIF4E-binding protein family.

Research Fields

· Cellular Processes > Cell growth and death > Cellular senescence.   (View pathway)

· Environmental Information Processing > Signal transduction > ErbB signaling pathway.   (View pathway)

· Environmental Information Processing > Signal transduction > HIF-1 signaling pathway.   (View pathway)

· Environmental Information Processing > Signal transduction > mTOR signaling pathway.   (View pathway)

· Environmental Information Processing > Signal transduction > PI3K-Akt signaling pathway.   (View pathway)

· Environmental Information Processing > Signal transduction > AMPK signaling pathway.   (View pathway)

· Genetic Information Processing > Translation > RNA transport.

· Human Diseases > Drug resistance: Antineoplastic > EGFR tyrosine kinase inhibitor resistance.

· Human Diseases > Infectious diseases: Viral > Human papillomavirus infection.

· Human Diseases > Cancers: Specific types > Acute myeloid leukemia.   (View pathway)

· Human Diseases > Cancers: Overview > Choline metabolism in cancer.   (View pathway)

· Organismal Systems > Aging > Longevity regulating pathway.   (View pathway)

· Organismal Systems > Endocrine system > Insulin signaling pathway.   (View pathway)


1). Functional characterization of DLK1/MEG3 locus on chromosome 14q32.2 reveals the differentiation of pituitary neuroendocrine tumors. Aging-US (PubMed: 33472171) [IF=5.2]

Application: WB    Species: Rat    Sample: GH3 cell

Figure 5 Effect of anit-DLK1 antibody on the bioactivity of PitNET cell lines. (A) Western blot assay measured the levels of DLK1 and PIT1 in GH3 cell line, MMQ cell line and ATT20 cell line. (B) Anti-DLK1 antibody inhibited the cell viability of GH3 cells in the dose- and time-dependent manner, not MMQ cells or ATT20 cells. (C) Anti-DLK1 antibody inhibited the secretion of GH/IGF-1 in GH3 cells, not PRL in MMQ cells and ACTH in ATT20 cells. (D) Clone forming experiment showed the anti-DLK1 antibody promoted the cell proliferation in GH3 cell line. (E) Confocal experiment showed DLK1 regulated the level of PIT1 in GH3 cell line. (F) Western blot experiment showed Anti-DLK1 antibody activated the mTOR pathway in GH3 cell line. *compare to control group P<0.05 **P<0.01 ***P<0.001.

2). Fluoxetine regulates mTOR signalling in a region-dependent manner in depression-like mice. Scientific Reports (PubMed: 26522512) [IF=4.6]

Application: WB    Species: mouse    Sample: mouse

Figure 5. Effect of fluoxetine (20mg/kg) and rapamycin (10mg/kg) on the level of phosphorylated-4E-BP-1 expression in the frontal cortex (A), the hippocampus (B), the amygdala (C) and the hypothalamus (D). The data represented the values of mean± S.E.M. from 5mice/group. # P< 0.05 and ##P< 0.01 vs Control-vehicle group. *P< 0.05 and **P< 0.01 vs CUMS-vehicle group. +P< 0.05 vs CUMS-fluoxetine group. The results of Two-way ANOVA are provided in supplemental materials.

3). The DLK1/MEG3 Locus is Related to the Differentiation of Pituitary Neuroendocrine Tumors. Research Square

Restrictive clause


Affinity Biosciences tests all products strictly. Citations are provided as a resource for additional applications that have not been validated by Affinity Biosciences. Please choose the appropriate format for each application and consult Materials and Methods sections for additional details about the use of any product in these publications.

For Research Use Only.
Not for use in diagnostic or therapeutic procedures. Not for resale. Not for distribution without written consent. Affinity Biosciences will not be held responsible for patent infringement or other violations that may occur with the use of our products. Affinity Biosciences, Affinity Biosciences Logo and all other trademarks are the property of Affinity Biosciences LTD.