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Product listing: XBP-1s (E8C2Z) Mouse mAb, UniProt ID P17861-2 #27901 to DDX5 Antibody, UniProt ID P17844 #4387

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Chromatin IP, Flow Cytometry, Immunofluorescence (Immunocytochemistry), Western Blotting

Background: Following protein synthesis, secretory, intra-organellar, and transmembrane proteins translocate into the endoplasmic reticulum (ER) where they are post-translationally modified and properly folded. The accumulation of unfolded proteins within the ER triggers an adaptive mechanism known as the unfolded protein response (UPR) that counteracts compromised protein folding (1). The transmembrane serine/threonine kinase IRE1, originally identified in Saccharomyces cerevisiae, is a proximal sensor for the UPR that transmits the unfolded protein signal across the ER membrane (2-4). The human homolog IRE1α was later identified and is ubiquitously expressed in human tissues (5). Upon activation of the unfolded protein response, IRE1α splices X-box binding protein 1 (XBP-1) mRNA through an unconventional mechanism using its endoribonuclease activity (6). This reaction converts XBP-1 from an unspliced XBP-1u isoform to the spliced XBP-1s isoform, which is a potent transcriptional activator that induces expression of many UPR responsive genes (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: Following protein synthesis, secretory, intra-organellar, and transmembrane proteins translocate into the endoplasmic reticulum (ER) where they are post-translationally modified and properly folded. The accumulation of unfolded proteins within the ER triggers an adaptive mechanism known as the unfolded protein response (UPR) that counteracts compromised protein folding (1). The transmembrane serine/threonine kinase IRE1, originally identified in Saccharomyces cerevisiae, is a proximal sensor for the UPR that transmits the unfolded protein signal across the ER membrane (2-4). The human homolog IRE1α was later identified and is ubiquitously expressed in human tissues (5). Upon activation of the unfolded protein response, IRE1α splices X-box binding protein 1 (XBP-1) mRNA through an unconventional mechanism using its endoribonuclease activity (6). This reaction converts XBP-1 from an unspliced XBP-1u isoform to the spliced XBP-1s isoform, which is a potent transcriptional activator that induces expression of many UPR responsive genes (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: 5'-3' exoribonuclease 2 (XRN2) is a nuclear exonuclease that degrades RNA containing a 5’-monophosphate to component mononucleotides. XRN2 also plays an important role in the termination of transcription at the 3’-end of genes by displacing RNA polymerase II (RNAPII) from the DNA strand (1,2). According to the ‘torpedo’ model of transcription termination, XRN2 gains access to the 5’ phosphate of the nascent RNA during co-transcriptional polyadenylation site cleavage. XRN2 degrades RNA at a faster rate than RNAPII-mediated RNA synthesis, resulting in the eviction of RNAPII from the template (3-5). In addition, XRN2 is essential for maturation of 5.8S and 28S ribosomal RNA and small nucleolar RNA molecules (2). Several research studies suggest that XRN2 plays a role in the quality control check of RNA molecules. XRN2 co-transcriptionally degrades aberrant nuclear mRNA transcripts that result from defective 5’mRNA capping, splicing, or 3’end formation (6). XRN2 exonuclease rapidly degrades hypomodified tRNA and excess miRNA molecules, indicating that XRN2 likely regulates tRNA and miRNA quality control as well (7-9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The zinc finger protein ZPR1 (ZNF259) binds to epidermal growth factor receptor (EGFR) and is localized to both cytoplasm and nucleus. The zinc fingers found in ZPR1 and the tyrosine kinase domain of EGFR mediate the interaction between ZPR1 and the receptor (1). ZPR1 translocates from the cytoplasm to nucleus following mitogen (i.e. EGF) stimulation (2,3). ZPR1 also interacts with translation elongation factor eEF1A in vivo following EGF treatment (3). The interaction between the zinc finger protein and elongation factor is important for cell proliferation. Cells lacking ZPR1 exhibit abnormal nucleolar function, suggesting that ZPR1 is required for cell viability and nucleolar function in dividing cells (3). ZPR1 knockout mice exhibit significant neurodegeneration, and reduced or altered expression of ZPR1 may contribute to spinal muscular atrophy, a disorder characterized by degeneration of spinal cord neurons (4).

$469
Reagents for 4 x 96 well plates
1 Kit
CST's PathScan® Phospho-4E-BP1 (Thr37/Thr46) Sandwich ELISA Antibody Pair is offered as an economical alternative to our PathScan® Phospho-4E-BP1 (Thr37/Thr46) Sandwich ELISA Kit #7216. Capture and Detection antibodies (100X stocks) and HRP-conjugated secondary antibody (1000X stock) are supplied. Sufficient reagents are supplied for 4 x 96 well ELISAs. The Phospho-4E-BP1 (Thr37/Thr46) Capture Antibody is coated in PBS overnight in a 96 well microplate. After blocking, cell lysates are added followed by a 4E-BP1 Detection Antibody and anti-Mouse IgG, HRP conjugated antibody. HRP substrate, TMB, is added for color development. The magnitude of the absorbance for this developed color is proportional to the quantity of Phospho-4E-BP1 (Thr37/Thr46) protein.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Monkey, Mouse, Rat

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$489
96 assays
1 Kit
CST's PathScan® Phospho-4E-BP1 (Thr37/46) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of 4E-BP1 when phosphorylated at Thr37/46. A Phospho-4E-BP1 (Thr37/46) Rabbit Antibody has been coated onto the microwells. After incubation with cell lysates, phospho-4E-BP1 (Thr37/46) is captured by the coated antibody. Following extensive washing, a 4E-BP1 Mouse Detection Antibody is added to detect the captured phospho-4E-BP1 protein. Anti-mouse IgG, HRP-linked Antibody #7076 is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of absorbance for this developed color is proportional to the quantity of 4E-BP1 phosphorylated at Thr37/46.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Monkey, Mouse, Rat

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$489
96 assays
1 Kit
The PathScan® Phospho-eIF2α (Ser51) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of eIF2α phosphorylated at Ser51. A eIF2α rabbit antibody has been coated onto the microwells. After incubation with cell lysates, eIF2α protein is captured by the coated antibody. Following extensive washing, a phospho-eIF2α (Ser51) mouse detection antibody is added to detect captured phospho-eIF2α protein. Anti-mouse IgG, HRP-linked antibody is then used to recognize the bound mouse detection antibody. HRP substrate TMB is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of eIF2α phosphorylated at Ser51.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: Phosphorylation of the eukaryotic initiation factor 2 (eIF2) α subunit is a well-documented mechanism to downregulate protein synthesis under a variety of stress conditions. eIF2 binds GTP and Met-tRNAi and transfers Met-tRNA to the 40S subunit to form the 43S preinitiation complex (1,2). eIF2 promotes a new round of translation initiation by exchanging GDP for GTP, a reaction catalyzed by eIF2B (1,2). Kinases that are activated by viral infection (PKR), endoplasmic reticulum stress (PERK/PEK), amino acid deprivation (GCN2), or heme deficiency (HRI) can phosphorylate the α subunit of eIF2 (3,4). This phosphorylation stabilizes the eIF2-GDP-eIF2B complex and inhibits the turnover of eIF2B. Induction of PKR by IFN-γ and TNF-α induces potent phosphorylation of eIF2α at Ser51 (5,6).

$489
96 assays
1 Kit
The PathScan® Phospho-eIF4E (Ser209) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of eIF4E when phosphorylated at Ser209. An eIF4E mouse antibody has been coated onto the microwells. After incubation with cell lysates, eIF4E (phospho and nonphospho) is captured by the coated antibody. Following extensive washing, a Phospho-eIF4E (Ser209) rabbit detection antibody is added to the captured phospho and nonphospho eIF4E protein. Anti-rabbit IgG, HRP-linked Antibody #7074 is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of phospho-eIF4E (Ser209).Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human

Background: Eukaryotic initiation factor 4E (eIF4E) binds to the mRNA cap structure to mediate the initiation of translation (1,2). eIF4E interacts with eIF4G, a scaffold protein that promotes assembly of eIF4E and eIF4A into the eIF4F complex (2). eIF4B is thought to assist the eIF4F complex in translation initiation. Upon activation by mitogenic and/or stress stimuli mediated by Erk and p38 MAPK, Mnk1 phosphorylates eIF4E at Ser209 in vivo (3,4). Two Erk and p38 MAPK phosphorylation sites in mouse Mnk1 (Thr197 and Thr202) are essential for Mnk1 kinase activity (3). The carboxy-terminal region of eIF4G also contains serum-stimulated phosphorylation sites, including Ser1108, Ser1148, and Ser1192 (5). Phosphorylation at these sites is blocked by the PI3 kinase inhibitor LY294002 and by the FRAP/mTOR inhibitor rapamycin.

$489
96 assays
1 Kit
The PathScan® Phospho-mTOR (Ser2448) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of mTOR protein phosphorylated at Ser2448. A mTOR mouse antibody has been coated onto the microwells. After incubation with cell lysates, mTOR (phospho and nonphospho) protein is captured by the coated antibody. Following extensive washing, a phospho-mTOR (Ser2448) rabbit antibody is added to detect the captured phospho-mTOR protein. Anti-rabbit IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of mTOR phosphorylated at Ser2448.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Monkey, Mouse, Rat

Background: The mammalian target of rapamycin (mTOR, FRAP, RAFT) is a Ser/Thr protein kinase (1-3) that functions as an ATP and amino acid sensor to balance nutrient availability and cell growth (4,5). When sufficient nutrients are available, mTOR responds to a phosphatidic acid-mediated signal to transmit a positive signal to p70 S6 kinase and participate in the inactivation of the eIF4E inhibitor, 4E-BP1 (6). These events result in the translation of specific mRNA subpopulations. mTOR is phosphorylated at Ser2448 via the PI3 kinase/Akt signaling pathway and autophosphorylated at Ser2481 (7,8). mTOR plays a key role in cell growth and homeostasis and may be abnormally regulated in tumors. For these reasons, mTOR is currently under investigation as a potential target for anti-cancer therapy (9).

$489
96 assays
1 Kit
The PathScan® Phospho-S6 Ribosomal Protein (Ser235/236) Chemiluminescent Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of phospho-S6 ribosomal protein (Ser235/236) with a chemiluminescent readout. Chemiluminescent ELISAs often have a wider dynamic range and higher sensitivity than conventional chromogenic detection. This chemiluminescent ELISA, which is offered in low volume microplates, shows increased signal and sensitivity while using smaller samples. A Phospho-S6 Ribosomal Protein (Ser235/236) Rabbit mAb has been coated on the microwells. After incubation with cell lysates, phospho-S6 ribosomal protein is captured by the coated antibody. Following extensive washing, a total S6 Ribosomal Protein Mouse mAb is added to detect the captured phospho-S6 ribosomal protein (Ser235/236). Anti-mouse IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. Chemiluminescent reagent is added for signal development. The magnitude of light emission, measured in relative light units (RLU), is proportional to the quantity of phospho-S6 ribosomal protein (Ser235/236).Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$489
96 assays
1 Kit
The PathScan® Phospho-S6 Ribosomal Protein (Ser235/236) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of phospho-S6 ribosomal protein (Ser235/236). A Phospho-S6 Ribosomal Protein (Ser235/236) Antibody has been coated onto the microwells. After incubation with cell lysates, only phospho-S6 ribosomal protein is captured by the coated antibody. Following extensive washing, a Total S6 Ribosomal Protein Mouse mAb is added to detect the captured phospho-S6 ribosomal protein (Ser235/236). Anti-Mouse IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of optical density for this developed color is proportional to the quantity of phospho-S6 ribosomal protein (Ser235/236).Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$489
96 assays
1 Kit
PathScan® Phospho-S6 Ribosomal Protein (Ser240/244) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of phosphorylated S6 ribosomal protein at Ser240/244. A Phospho-S6 Ribosomal Protein (Ser240/244) Rabbit mAb has been coated onto the microwells. After incubation with cell lysates, phospho-S6 ribosomal protein (Ser240/244) is captured by the coated antibody. Following extensive washing, an S6 Ribosomal Protein Mouse Detection mAb is added to detect the captured phospho-S6 ribosomal protein. Anti-mouse IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of absorbance for the developed color is proportional to the quantity of S6 ribosomal protein phosphorylated at Ser240/244.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$489
96 assays
1 Kit
CST's PathScan® Total 4E-BP1 Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of 4E-BP1. A 4E-BP1 Rabbit Antibody has been coated onto the microwells. After incubation with cell lysates, 4E-BP1 (phospho and nonphospho) is captured by the coated antibody. Following extensive washing, a 4E-BP1 Mouse Detection Antibody is added to detect the captured 4E-BP1 protein. Anti-mouse IgG, HRP-linked Antibody #7076 is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of absorbance for this developed color is proportional to the quantity of total 4E-BP1.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$489
96 assays
1 Kit
The PathScan® Total eIF2α Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of eIF2α protein. A eIF2α rabbit antibody has been coated onto the microwells. After incubation with cell lysates, eIF2α (phospho and nonphospho) is captured by the coated antibody. Following extensive washing, a eIF2α mouse antibody is added to detect captured eIF2α protein. Anti-rabbit IgG, HRP-linked antibody is then used to recognize the bound detection antibody. HRP substrate (TMB) is added to develop color. The magnitude of the absorbance for this developed color is proportional to the quantity of total eIF2α protein.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human

Background: Phosphorylation of the eukaryotic initiation factor 2 (eIF2) α subunit is a well-documented mechanism to downregulate protein synthesis under a variety of stress conditions. eIF2 binds GTP and Met-tRNAi and transfers Met-tRNA to the 40S subunit to form the 43S preinitiation complex (1,2). eIF2 promotes a new round of translation initiation by exchanging GDP for GTP, a reaction catalyzed by eIF2B (1,2). Kinases that are activated by viral infection (PKR), endoplasmic reticulum stress (PERK/PEK), amino acid deprivation (GCN2), or heme deficiency (HRI) can phosphorylate the α subunit of eIF2 (3,4). This phosphorylation stabilizes the eIF2-GDP-eIF2B complex and inhibits the turnover of eIF2B. Induction of PKR by IFN-γ and TNF-α induces potent phosphorylation of eIF2α at Ser51 (5,6).

$489
96 assays
1 Kit
The PathScan® Total S6 Ribosomal Protein Chemiluminescent Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of total S6 ribosomal protein with a chemiluminescent readout. Chemiluminescence ELISAs often have a wider dynamic range and higher sensitivity than conventional chromogenic detection. This chemiluminescent ELISA, which is offered in low volume microplates, shows increased signal and sensitivity while using smaller sample size. A S6 Ribosomal Protein Mouse mAb has been coated on the microwells. After incubation with cell lysates, the S6 ribosomal protein is captured by the coated antibody. Following extensive washing, S6 Ribosomal Protein Rabbit Antibody is added to detect the captured total S6 ribosomal protein. Anti-rabbit IgG, HRP-linked Antibody is then used to recognize the bound detection antibody. Chemiluminescent reagent is added for signal development. The magnitude of light emission, measured in relative light units (RLU), is proportional to the quantity of total S6 ribosomal protein.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$489
96 assays
1 Kit
The PathScan® Total S6 Ribosomal Protein Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of total S6 ribosomal protein. An S6 Ribosomal Protein Mouse mAb has been coated onto the microwells. After incubation with cell lysates, both phospho- and nonphospho-S6 ribosomal proteins are captured by the coated antibody. Following extensive washing, S6 Ribosomal Protein Antibody is added to detect phospho- and nonphospho-S6 ribosomal proteins. HRP-linked Anti-rabbit Antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of optical density is proportional to the quantity of total ribosomal protein.Antibodies in kit are custom formulations specific to kit.
REACTIVITY
Human, Mouse

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$320
100 µg
This peptide is used to block Phospho-4E-BP1 (Thr37/46) (236B4) Rabbit mAb #2855 reactivity.
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunohistochemistry (Paraffin)

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

This peptide is used to block Phospho-eIF2alpha (Ser51) (119A11) Rabbit mAb (#3597) and Phospho-eIF2α (Ser51) (D9G8) XP® Rabbit mAb (#3398).

Background: Phosphorylation of the eukaryotic initiation factor 2 (eIF2) α subunit is a well-documented mechanism to downregulate protein synthesis under a variety of stress conditions. eIF2 binds GTP and Met-tRNAi and transfers Met-tRNA to the 40S subunit to form the 43S preinitiation complex (1,2). eIF2 promotes a new round of translation initiation by exchanging GDP for GTP, a reaction catalyzed by eIF2B (1,2). Kinases that are activated by viral infection (PKR), endoplasmic reticulum stress (PERK/PEK), amino acid deprivation (GCN2), or heme deficiency (HRI) can phosphorylate the α subunit of eIF2 (3,4). This phosphorylation stabilizes the eIF2-GDP-eIF2B complex and inhibits the turnover of eIF2B. Induction of PKR by IFN-γ and TNF-α induces potent phosphorylation of eIF2α at Ser51 (5,6).

$320
100 µg
This peptide is used to block Phospho-S6 Ribosomal Protein (Ser235/236) Antibody #2211 reactivity.
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

PhosphoPlus® Duets from Cell Signaling Technology (CST) provide a means to assess protein activation status. Each Duet contains an activation-state and total protein antibody to your target of interest. These antibodies have been selected from CST's product offering based upon superior performance in specified applications.

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$260
100 µl
$630
300 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Bovine, Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry, Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: During translation, eIF4E binds to the 5' cap structure of mRNA and helps mRNA bind to the ribosome. There are several factors that associate with eIF4E. One of these factors is eIF4E-Transporter (4E-T) (1). 4E-T has an eIF4E binding site, a nuclear localization signal and two nuclear export signals (1). Studies demonstrate that 4E-T functions as a nucleocytoplasmic shuttling protein mediating the import of eIF4E into the nucleus (1). Recent findings indicate that 4E-T, along with eIF4E, is concentrated in the processing bodies (P-bodies) in the cytoplasm (2). Furthermore, 4E-T decreases mRNA stability (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Small non-coding RNAs are important regulators of gene expression in higher eukaryotes (1,2). Several classes of small RNAs, including short interfering RNAs (siRNAs) (3), microRNAs (miRNAs) (4), and Piwi-interacting RNAs (piRNAs) (5), have been identified. MicroRNAs are about 21 nucleotides in length and have been implicated in many cellular processes such as development, differentiation, and stress response (1,2). MicroRNAs regulate gene expression by modulating mRNA translation or stability (2). MicroRNAs function together with the protein components in the complexes called micro-ribonucleoproteins (miRNPs) (2). Among the most important components in these complexes are Argonaute proteins (1,2). There are four members in the mammalian Argonaute family and only Argonaute 2 (Ago2) possesses the Slicer endonuclease activity (1,2). Argonaute proteins participate in the various steps of microRNA-mediated gene silencing, such as repression of translation and mRNA turnover (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: Butyrate response factor 1 (BRF1; also known as EGF response factor 1 [ERF1], TIS11B, ZFP36L1) and butyrate response factor 2 (BRF2; also known as EGF response factor 2 [ERF2], TIS11D, ZFP36L2) both belong to the TIS11 family of CCCH zinc-finger proteins (1). This family of proteins, which also includes tristetraprolin (TTP), bind to AU-rich elements (ARE) found in the 3'-untranslated regions of mRNAs and promote de-adenylation and rapid degradation by the exosome (2,3). These proteins play a critical role in cell growth control by regulating the mRNA turnover of multiple cytokines, growth factors and cell cycle regulators, including GM-CSF, TNFα, IL-2, IL-3 and IL-6 (4,5). Deregulated ARE-mRNA stability can contribute to both inflammation and oncogenic transformation (6-8). Insulin-induced stabilization of ARE-containing transcripts is mediated by Akt/PKB phosphorylation of BRF1 at Ser92, which results in binding by 14-3-3 protein and inactivation of BRF1 (9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: Phosphorylated CTD Interacting Factor 1 (PCIF1), also known as CAPAM, is a WW domain-containing protein that was initially discovered to interact with phosphorylated RNA Polymerase II, where it inhibits CTD phosphatase activity of SCP1 to negatively affect gene expression (1,2). CAPAM/PCIF1 has shown to be the methyltransferase responsible for methylating the adenosine at the second position of mRNAs, promoting their translation (3,4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: The cdc2-like kinase (CLK) family contains at least four highly conserved isoforms: CLK1, CLK2, CLK3 and CLK4 (1,2). CLKs are dual specificity kinases that autophosphorylate on serine, threonine and tyrosine residues and phosphorylate exogenous substrates on serine and threonine residues (2). CLK family members exist as both a full-length catalytically active form and an alternatively-spliced, inactive truncated form (1). A family of highly phosphorylated proteins, called serine and arginine rich (SR) proteins, are phosphorylated by CLKs (3-5). SR proteins are splicing factors that regulate the assembly of the spliceosome, a macromolecular complex where RNA splicing occurs in the nucleus. They are also involved in the selection of splice sites. Thus, CLKs may play important roles in regulating RNA splicing.

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Cleavage and polyadenylation of pre-mRNA is regulated by a core group of proteins called the cleavage and polyadenylation specificity factors (1,2). The CPSF factors interact with poly(A) polymerase (PAP) to recognize the AAUAAA sequence motif and add poly(A). CPSF can also interact with downstream cleavage factors to precisely cleave the 3’ end of pre-mRNA (2,3). CPSF is brought to 3’ ends by the carboxy-terminal domain of the Rpb1 subunit of the RNA Polymerase II complex, where it dissociates and initiates polyadenylation (4). CPSF has been shown to have numerous interactions with viral proteins. The influenza NS1 viral protein binds to CPSF4 to prevent 3’ end processing of viral RNAs, inhibiting nuclear export (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Hamster, Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The DEAD box family of RNA helicases is characterized in part by a common D-E-A-D amino acid motif. The family is composed of a growing number of proteins found in a wide range of organisms from bacteria to mammals. DEAD helicases have distinct biological functions in RNA metabolism and ribonucleoprotein (RNP) processing (reviewed in 1,2).DDX3 is a DEAD box family RNA helicase with diverse cellular functions. DDX3 is required for nuclear export of HIV-1 viral transcripts, possibly in a complex with the viral Rev protein and host cofactor CRM1 (3). DDX3 is required for hepatitis C virus (HCV) RNA replication (4) and its expression is downregulated in hepatitis B virus (HBV) associated hepatocellular carcinoma (HCC) (5).Recent evidence suggests that DDX3 functions as a tumor suppressor protein. Its expression inhibits tumor cell colony formation and increases expression of the cdk inhibitor p21 Waf1/Cip1. Low DDX3 expression has been shown in HCC (5,6), and aberrant subcellular localization occurs in many squamous cell carcinomas (6). Reduced DDX3 expression in cultured cells causes a diminished dependence on serum for cell proliferation and changes in cyclin D1 and p21 Waf1/Cip1 expression (5).DDX3 is phosphorylated at Thr204 and Thr323 by the mitotic cyclin dependent kinase, cyclin B/cdc2. This phosphorylation is thought to cause a loss of DDX3 function and a concomitant repression of ribosome biogenesis and translation in mitosis (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: DDX5 (DEAD box polypeptide 5), also known as p68, was first identified as a 68 kDa nuclear protein with similarity to translation initiation factor eIF-4A (1). DDX5 is a member of the DEAD box family of putative RNA helicases, defined by the presence of a conserved DEAD (Asp-Glu-Ala-Asp) motif that appears to function primarily in the regulation of RNA secondary structure. DDX5 exhibits ATP-dependent RNA helicase activity (2) and has been identified as a critical subunit of the DROSHA complex that regulates miRNA and rRNA processing (3,4). DDX may also regulate mRNA splicing (5) and has been shown to interact with HDAC1, where it can regulate promoter-specific transcription (6). DDX5 interacts with a diverse group of proteins, including Runx2, p53, Smad3, CBP, and p300 (7-10), suggesting an important role for DDX5 in a multitude of developmental processes. Notably, DDX5 may be involved in growth factor-induced epithelial mesechymal transition (EMT). Phosphorylation of DDX5 at Tyr593 following PDGF stimulation was shown to displace Axin from β-catenin; this prevented phosphorylation of β-catenin by GSK-3β, leading to Wnt-independent nuclear translocation of β-catenin (11) and increased transcription of c-Myc, cyclin D1, and Snai1 (12,13).