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Product listing: GSK-3α (D80D1) XP® Rabbit mAb, UniProt ID P49840 #4818 to SimpleChIP® Human NPM1 Intron 1 Primers, UniProt ID P06748 #4779

$293
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunofluorescence (Immunocytochemistry)

Background: Glycogen synthase kinase-3 (GSK-3) was initially identified as an enzyme that regulates glycogen synthesis in response to insulin (1). GSK-3 is a ubiquitously expressed serine/threonine protein kinase that phosphorylates and inactivates glycogen synthase. GSK-3 is a critical downstream element of the PI3K/Akt cell survival pathway whose activity can be inhibited by Akt-mediated phosphorylation at Ser21 of GSK-3α and Ser9 of GSK-3β (2,3). GSK-3 has been implicated in the regulation of cell fate in Dictyostelium and is a component of the Wnt signaling pathway required for Drosophila, Xenopus, and mammalian development (4). GSK-3 has been shown to regulate cyclin D1 proteolysis and subcellular localization (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Striatal enriched phosphatase (STEP, also known as PTPN5), is a protein tyrosine phosphatase expressed in dopaminoceptive neurons of the central nervous system (1). Alternative splicing produces the cytosolic STEP46 and the membrane-associated STEP61 isoforms of STEP. Dopamine activates D1 receptors and PKA, which in turn phosphorylate both isoforms of STEP. Phosphorylation of STEP61 occurs at Ser160 and Ser221, while STEP46 is phosphorylated at Ser49 (equivalent to Ser221 of STEP61) (2). NMDA-mediated activation of STEP is an important mechanism for regulation of Erk activity in neurons (3). Furthermore, STEP is involved in the regulation of both NMDAR and AMPAR trafficking (4,5). Due to its importance in cognitive function, STEP may play a role in Alzheimer's disease (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: RANK (receptor activator of NF-κB) is a member of the tumor necrosis factor (TNF) receptor subfamily that is activated by its ligand, RANKL (TRANCE/OPGL/ODF), to promote survival of dendritic cells and differentiation of osteoclasts (1-4). Although RANK is widely expressed, its cell surface expression may be more restricted to dendritic cells and foreskin fibroblasts (1). RANK contains a 383-amino acid intracellular domain that associates with specific members of the TRAF family to NF-κB and JNK activiation (1,5). RANKL/RANK signaling may also lead to survival signaling through activation of the Akt pathway and an upregulation of survival proteins, including Bcl-xL (2,6). RANK signaling has been implicated as a potential therapeutic to inhibit bone loss and arthritis (7,8).

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

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

Background: The NF-κB/Rel transcription factors are present in the cytosol in an inactive state complexed with the inhibitory IκB proteins (1-3). Activation occurs via phosphorylation of IκBα at Ser32 and Ser36 followed by proteasome-mediated degradation that results in the release and nuclear translocation of active NF-κB (3-7). IκBα phosphorylation and resulting Rel-dependent transcription are activated by a highly diverse group of extracellular signals including inflammatory cytokines, growth factors, and chemokines. Kinases that phosphorylate IκB at these activating sites have been identified (8).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Ubiquitinating enzymes (UBEs) catalyze protein ubiquitination, a reversible process countered by deubiquitinating enzyme (DUB) action. Five DUB subfamilies are recognized, including the USP, UCH, OTU, MJD and JAMM enzymes (1,2). USP18 (also known as UBP43) is a deubiquitinase best known for catalyzing the removal of ISG15, an interferon-regulated ubibiquitin-like protein, from conjugated proteins (3). Removal of ISG15 from target proteins by the USP18 peptidase maintains the critical cellular balance of ISG15-conjugated proteins important for normal development and brain function (4,5). Following induction by IFN or LPS (6), USP18 binds the INF receptor subunit IFNAR2 and inhibits signal transduction through the JAK-STAT pathway (7). USP18 regulation of IFN signaling inhibits IFN-mediated apoptosis and does not necessarily rely on USP18 peptidase activity (8). As the therapeutic use of recombinant IFN can lead to refractory IFN signaling and a less effective response, the combination of IFN treatment and regulation of USP18 expression may produce a more positive outcome (9).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: The NF-κB/Rel transcription factors are present in the cytosol in an inactive state complexed with the inhibitory IκB proteins (1-3). Activation occurs via phosphorylation of IκBα at Ser32 and Ser36 followed by proteasome-mediated degradation that results in the release and nuclear translocation of active NF-κB (3-7). IκBα phosphorylation and resulting Rel-dependent transcription are activated by a highly diverse group of extracellular signals including inflammatory cytokines, growth factors, and chemokines. Kinases that phosphorylate IκB at these activating sites have been identified (8).

$305
100 µl
This Cell Signaling Technology antibody is conjugated to biotin under optimal conditions. The biotinylated antibody is expected to exhibit the same species cross-reactivity as the unconjugated AMPKα (D5A2) Rabbit mAb #5831.
APPLICATIONS
REACTIVITY
Bovine, Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: AMP-activated protein kinase (AMPK) is highly conserved from yeast to plants and animals and plays a key role in the regulation of energy homeostasis (1). AMPK is a heterotrimeric complex composed of a catalytic α subunit and regulatory β and γ subunits, each of which is encoded by two or three distinct genes (α1, 2; β1, 2; γ1, 2, 3) (2). The kinase is activated by an elevated AMP/ATP ratio due to cellular and environmental stress, such as heat shock, hypoxia, and ischemia (1). The tumor suppressor LKB1, in association with accessory proteins STRAD and MO25, phosphorylates AMPKα at Thr172 in the activation loop, and this phosphorylation is required for AMPK activation (3-5). AMPKα is also phosphorylated at Thr258 and Ser485 (for α1; Ser491 for α2). The upstream kinase and the biological significance of these phosphorylation events have yet to be elucidated (6). The β1 subunit is post-translationally modified by myristoylation and multi-site phosphorylation including Ser24/25, Ser96, Ser101, Ser108, and Ser182 (6,7). Phosphorylation at Ser108 of the β1 subunit seems to be required for the activation of AMPK enzyme, while phosphorylation at Ser24/25 and Ser182 affects AMPK localization (7). Several mutations in AMPKγ subunits have been identified, most of which are located in the putative AMP/ATP binding sites (CBS or Bateman domains). Mutations at these sites lead to reduction of AMPK activity and cause glycogen accumulation in heart or skeletal muscle (1,2). Accumulating evidence indicates that AMPK not only regulates the metabolism of fatty acids and glycogen, but also modulates protein synthesis and cell growth through EF2 and TSC2/mTOR pathways, as well as blood flow via eNOS/nNOS (1).

$122
20 µl
$303
100 µl
$717
300 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: Transcription factors of the nuclear factor κB (NF-κB)/Rel family play a pivotal role in inflammatory and immune responses (1,2). There are five family members in mammals: RelA, c-Rel, RelB, NF-κB1 (p105/p50), and NF-κB2 (p100/p52). Both p105 and p100 are proteolytically processed by the proteasome to produce p50 and p52, respectively. Rel proteins bind p50 and p52 to form dimeric complexes that bind DNA and regulate transcription. In unstimulated cells, NF-κB is sequestered in the cytoplasm by IκB inhibitory proteins (3-5). NF-κB-activating agents can induce the phosphorylation of IκB proteins, targeting them for rapid degradation through the ubiquitin-proteasome pathway and releasing NF-κB to enter the nucleus where it regulates gene expression (6-8). NIK and IKKα (IKK1) regulate the phosphorylation and processing of NF-κB2 (p100) to produce p52, which translocates to the nucleus (9-11).

$303
50 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunohistochemistry (Paraffin)

Background: Transcription factors of the nuclear factor κB (NF-κB)/Rel family play a pivotal role in inflammatory and immune responses (1,2). There are five family members in mammals: RelA, c-Rel, RelB, NF-κB1 (p105/p50), and NF-κB2 (p100/p52). Both p105 and p100 are proteolytically processed by the proteasome to produce p50 and p52, respectively. Rel proteins bind p50 and p52 to form dimeric complexes that bind DNA and regulate transcription. In unstimulated cells, NF-κB is sequestered in the cytoplasm by IκB inhibitory proteins (3-5). NF-κB-activating agents can induce the phosphorylation of IκB proteins, targeting them for rapid degradation through the ubiquitin-proteasome pathway and releasing NF-κB to enter the nucleus where it regulates gene expression (6-8). NIK and IKKα (IKK1) regulate the phosphorylation and processing of NF-κB2 (p100) to produce p52, which translocates to the nucleus (9-11).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Stat5 is activated in response to a wide variety of ligands including IL-2, GM-CSF, growth hormone and prolactin. Phosphorylation at Tyr694 is obligatory for Stat5 activation (1,2). This phosphorylation is mediated by Src upon erythropoietin stimulation (3). Stat5 is constitutively active in some leukemic cell types (4). Phosphorylated Stat5 is found in some endothelial cells treated with IL-3, which suggests its involvement in angiogenesis and cell motility (5). Stat5a and Stat5b are independently regulated and activated in various cell types. For instance, interferon treatment predominantly activates Stat5a in U-937 cells and Stat5b in HeLa cells (6).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Transcription factors of the nuclear factor κB (NF-κB)/Rel family play a pivotal role in inflammatory and immune responses (1,2). There are five family members in mammals: RelA, c-Rel, RelB, NF-κB1 (p105/p50), and NF-κB2 (p100/p52). Both p105 and p100 are proteolytically processed by the proteasome to produce p50 and p52, respectively. Rel proteins bind p50 and p52 to form dimeric complexes that bind DNA and regulate transcription. In unstimulated cells, NF-κB is sequestered in the cytoplasm by IκB inhibitory proteins (3-5). NF-κB-activating agents can induce the phosphorylation of IκB proteins, targeting them for rapid degradation through the ubiquitin-proteasome pathway and releasing NF-κB to enter the nucleus where it regulates gene expression (6-8). NIK and IKKα (IKK1) regulate the phosphorylation and processing of NF-κB2 (p100) to produce p52, which translocates to the nucleus (9-11).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: Structural maintenance of chromosomes 1 (SMC1) protein is a chromosomal protein member of the cohesin complex that enables sister chromatid cohesion and plays a role in DNA repair (1,2). ATM/NBS1-dependent phosphorylation of SMC1 occurs at Ser957 and Ser966 in response to ionizing radiation (IR) as part of the intra-S-phase DNA damage checkpoint (3). SMC1 phosphorylation is ATM-independent in cells subjected to other forms of DNA damage, including UV light and hydroxyurea treatment (4). While phosphorylation of SMC1 is required for activation of the IR-induced intra-S-phase checkpoint, the precise mechanism is not well understood and may involve a conformational change that affects SMC1-SMC3 interaction (3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: DCBLD2 (discoidin, CUB and LCCL domain-containing 2; also known as ESDN and CLCP1) is a type I transmembrane protein that is structurally similar to neuropilin family proteins and contains the longest known amino-terminal secretory signal sequence among eukaryotic proteins (1). Highly expressed in nerve bundles, vascular smooth muscle cells and upregulated following vascular injury, DCBLD2 may be involved in a wide range of functions in the nervous and vascular systems (1,2). Studies have found DCBLD2 to be upregulated in several types of lung cancer with an especially high frequency in metastatic lesions and lymph node metastasis, implicating a role in the process of tumor progression and metastatic capability (3). DCBLD2 has also been identified as part of a complex EGF phosphotyrosine signaling network, serving as a novel tyrosine phosphorylation target of EGF signaling in human cancer cells (4).

$364
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-S6 Ribosomal Protein (Ser235/236) (D57.2.2E) XP® Rabbit mAb #4858.
APPLICATIONS
REACTIVITY
Human, Mink, Monkey, Mouse, Rat, S. cerevisiae

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry)

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
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: Structural maintenance of chromosomes 1 (SMC1) protein is a chromosomal protein member of the cohesin complex that enables sister chromatid cohesion and plays a role in DNA repair (1,2). ATM/NBS1-dependent phosphorylation of SMC1 occurs at Ser957 and Ser966 in response to ionizing radiation (IR) as part of the intra-S-phase DNA damage checkpoint (3). SMC1 phosphorylation is ATM-independent in cells subjected to other forms of DNA damage, including UV light and hydroxyurea treatment (4). While phosphorylation of SMC1 is required for activation of the IR-induced intra-S-phase checkpoint, the precise mechanism is not well understood and may involve a conformational change that affects SMC1-SMC3 interaction (3).

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

Application Methods: Western Blotting

Background: RalA and RalB are members of the Ras family of small GTPases and are highly homologous in protein sequence. The functions of RalA and RalB are distinct yet overlapping. By binding to various effector proteins, RalA and RalB serve as important GTP sensors for exocytosis and membrane trafficking (1-3). RalA is required for Ras-related tumorigenesis (4) and RalB is important for tumor survival (5). In addition to tumor formation, Ral proteins also play a role in cancer cell migration and metastatic tumor invasion (6,7).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: Clathrin-coated vesicles provide for the intracellular transport of cargo proteins following endocytosis and during multiple vesicle trafficking pathways. Vesicles form at specialized areas of the cell membrane where clathrin and associated proteins form clathrin-coated pits. Invagination of these cell membrane-associated pits internalizes proteins and forms an intracellular clathrin-coated vesicle (1,2). Clathrin is the most abundant protein in these vesicles and is present as a basic assembly unit called a triskelion. Each clathrin triskelion is composed of three clathrin heavy chains and three clathrin light chains. Clathrin heavy chain proteins are composed of several functional domains, including a carboxy-terminal region that permits interaction with other heavy chain proteins within a triskelion, and a globular amino-terminal region that associates with other vesicle proteins (2). Adaptor proteins, such as AP2, epsin and EPS15, are responsible for the recruitment of vesicle proteins to sites of pit formation and the assembly of the clathrin-coated vesicle. Following vesicle invagination, the GTPase dynamin constricts the neck of the nascent vesicle to complete formation of the free, cytosolic vesicle (3,4).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: Research studies have implicated the HER/ErbB receptor tyrosine kinase family in normal development, cardiac function and cancer (1,2). HER4/ErbB4, like other family members, has four ectodomains, a single transmembrane domain and a cytoplasmic tail containing the active tyrosine kinase domain (3). By binding to neuregulins and/or EGF family ligands, ErbB4 forms either a homodimer or heterodimer with other ErbB family members, which results in receptor activation and signaling (3). ErbB4 is ubiquitously expressed with the highest expression occurring in brain and heart. The expression of ErbB4 in breast cancer, pediatric brain cancer and other types of carcinomas has been reported in research studies suggesting that ErbB4 expression is involved in both normal tissue development and carcinogenesis (3).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: CDC37 is an important component of the HSP90 chaperone complex (1,2). It was initially identified for its involvement in cell-cycle progression and was later found to have a much broader role as a chaperone for a wide variety of kinases and other proteins (1-3). CDC37 protein has an amino-terminal kinase binding domain followed by a central HSP90 binding domain. It recruits and stabilizes kinases in the HSP90 complex by protecting the newly synthesized kinase peptide chain from degradation and promoting the next step of protein maturation (4,5). CDC37 also suppresses the ATPase activity of HSP90, thereby leading to conformational changes in the complex that preclude target kinase loading (6). CDC37 has been proposed as a therapeutic target because of its important role in multiple kinase pathways involved in proliferation and cancer cell survival, including Raf, Akt, Src, and ErbB2 pathways (7,8).

$307
100 µl
$719
300 µl
APPLICATIONS
REACTIVITY
Human, Mouse

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

Background: HER3/ErbB3 is a member of the ErbB receptor protein tyrosine kinase family, but it lacks tyrosine kinase activity. Tyrosine phosphorylation of ErbB3 depends on its association with other ErbB tyrosine kinases. Upon ligand binding, heterodimers form between ErbB3 and other ErbB proteins, and ErbB3 is phosphorylated on tyrosine residues by the activated ErbB kinase (1,2). There are at least 9 potential tyrosine phosphorylation sites in the carboxy-terminal tail of ErbB3. These sites serve as consensus binding sites for signal transducing proteins, including Src family members, Grb2, and the p85 subunit of PI3 kinase, which mediate ErbB downstream signaling (3). Both Tyr1222 and Tyr1289 of ErbB3 reside within a YXXM motif and participate in signaling to PI3K (4).Investigators have found that ErbB3 is highly expressed in many cancer cells (5) and activation of the ErbB3/PI3K pathway is correlated with malignant phenotypes of adenocarcinomas (6). Research studies have demonstrated that in tumor development, ErbB3 may function as an oncogenic unit together with other ErbB members (e.g. ErbB2 requires ErbB3 to drive breast tumor cell proliferation) (7). Thus, investigators view inhibiting interaction between ErbB3 and ErbB tyrosine kinases as a novel strategy for anti-tumor therapy.

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

Application Methods: Western Blotting

Background: Apoptosis induced through the CD95 receptor (Fas/APO-1) and tumor necrosis factor receptor 1 (TNFR1) activates caspase-8 and leads to the release of the caspase-8 active fragments, p18 and p10 (1-3). Activated caspase-8 cleaves and activates downstream effector caspases such as caspase-1, -3, -6, and -7. Caspase-3 ultimately elicits the morphological hallmarks of apoptosis, including DNA fragmentation and cell shrinkage.

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Nucleomethylin (NML), also known as ribosomal RNA-processing protein 8 (RRP8) and human cerebral protein 1 (Hucep-1), is a nucleolar protein (1,2). NML interacts with the histone de-acetylase protein SirT1 and histone methyl-transferase protein SUV39H1 to form the energy-dependent nucleolar silencing complex (eNoSC) that regulates ribosomal RNA (rRNA) transcription in response to changes in the energy state of the cell (2). As energy levels in the cell decrease due to caloric restriction, eNoSC binds to rRNA genes and represses transcription by SirT1-mediated de-acetylation of histones and SUV39H1-mediated methylation of histone H3 on Lys9. NML binds to di-methylated Lys9 of histone H3 and likely functions in the recruitment and spreading of eNoSC along the rRNA genes (2). NML also contains a methyltransferases-like domain, which binds to S-adenosyl-methionine (SAM) and is required for eNoSC function (2). By limiting the transcription of rRNA genes during caloric restriction, eNoSC promotes the restoration of energy balance and protects cells from energy-dependent apoptosis.

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Msh homeobox 1 (Msx1) is a Muscle Segment Homeobox (Msh) gene family member that acts as a transcriptional repressor during embryonic development, playing an important role in limb pattern formation, craniofacial development, and tooth development (1-3). Msx1 is expressed in the mesenchyme of the developing nail bed (2) and in fetal hair follicles, epidermis and fibroblasts; reduced expression is seen in adult epithelial-derived tissues (4). Msx1 acts in concert with the Wnt1 network to establish the midbrain dopaminergic progenator domain, a region that gives rise to neurons that are critical for normal brain function and are the cells affected in Parkinson disease (5). Mutation in the corresponding Msx1 gene correlates with abnormal tooth development in patients diagnosed with Wolf-Hirschhorn syndrome (6). Other genetic changes in the Msx1 gene result in Witkop Syndrome ("tooth and nail syndrome") and cases of abnormal tooth development associated with non-syndromic orofacial clefting (2,7).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: The process of SUMO-1 conjugation is similar to that seen with ubiquitin and other forms of post-translational protein modification (1). Like ubiquitin, SUMO-1 is conjugated to its target protein by the coordinated action of ubiquitin conjugation enzymes E1, E2 and E3 (2). Ubc9 (or ube2M) is a highly conserved, 158 amino acid protein that acts as a SUMO-1 conjugating enzyme (3). Ubc9 binds to target proteins through their SUMO-1-CS (consensus sequence) domains and interacts with SUMO via the structurally conserved amino-terminal domain (3,4). Localization of Ubc9 to the nucleus and the nuclear envelope allows this enzyme to catalyze target protein sumoylation and regulate target protein nucleocytoplasmic transport and transcriptional activity (5,6). Ubc9 target proteins include a host of proteins (RAD51, RAD52, p53 and c-Jun) that regulate the cell cycle, DNA repair, and p53-dependent processes (7).

$307
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: HER3/ErbB3 is a member of the ErbB receptor protein tyrosine kinase family, but it lacks tyrosine kinase activity. Tyrosine phosphorylation of ErbB3 depends on its association with other ErbB tyrosine kinases. Upon ligand binding, heterodimers form between ErbB3 and other ErbB proteins, and ErbB3 is phosphorylated on tyrosine residues by the activated ErbB kinase (1,2). There are at least 9 potential tyrosine phosphorylation sites in the carboxy-terminal tail of ErbB3. These sites serve as consensus binding sites for signal transducing proteins, including Src family members, Grb2, and the p85 subunit of PI3 kinase, which mediate ErbB downstream signaling (3). Both Tyr1222 and Tyr1289 of ErbB3 reside within a YXXM motif and participate in signaling to PI3K (4).Investigators have found that ErbB3 is highly expressed in many cancer cells (5) and activation of the ErbB3/PI3K pathway is correlated with malignant phenotypes of adenocarcinomas (6). Research studies have demonstrated that in tumor development, ErbB3 may function as an oncogenic unit together with other ErbB members (e.g. ErbB2 requires ErbB3 to drive breast tumor cell proliferation) (7). Thus, investigators view inhibiting interaction between ErbB3 and ErbB tyrosine kinases as a novel strategy for anti-tumor therapy.

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Heterogeneous nuclear ribonucleoprotein L-like (hnRNP LL) is a nuclear RNA-binding protein that shares 69% amino acid homology with hnRNP L, a component of the hnRNP complex that regulates mRNA formation, packaging, and processing (1). hnRNP LL is induced in activated T cells and functions as a critical regulator of alternative splicing of CD45, a tyrosine phosphatase crucial for T cell development and activation (2). hnRNP LL also regulates the splicing of CD44 and Stat5a (2). The four isoforms of hnRNP LL are generated by alternative splicing and are widely expressed in human tissues (3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: The second messenger cyclic AMP (cAMP) activates cAMP-dependent protein kinase (PKA or cAPK) in mammalian cells and controls many cellular mechanisms such as gene transcription, ion transport, and protein phosphorylation (1). Inactive PKA is a heterotetramer composed of a regulatory subunit (R) dimer and a catalytic subunit (C) dimer. In this inactive state, the pseudosubstrate sequences on the R subunits block the active sites on the C subunits. Three C subunit isoforms (C-α, C-β, and C-γ) and two families of regulatory subunits (RI and RII) with distinct cAMP binding properties have been identified. The two R families exist in two isoforms, α and β (RI-α, RI-β, RII-α, and RII-β). Upon binding of cAMP to the R subunits, the autoinhibitory contact is eased and active monomeric C subunits are released. PKA shares substrate specificity with Akt (PKB) and PKC, which are characterized by an arginine at position -3 relative to the phosphorylated serine or threonine residue (2). Substrates that present this consensus sequence and have been shown to be phosphorylated by PKA are Bad (Ser155), CREB (Ser133), and GSK-3 (GSK-3α Ser21 and GSK-3β Ser9) (3-5). In addition, combined knock-down of PKA C-α and -β blocks cAMP-mediated phosphorylation of Raf (Ser43 and Ser259) (6). Autophosphorylation and phosphorylation by PDK-1 are two known mechanisms responsible for phosphorylation of the C subunit at Thr197 (7).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The second messenger cyclic AMP (cAMP) activates cAMP-dependent protein kinase (PKA or cAPK) in mammalian cells and controls many cellular mechanisms such as gene transcription, ion transport, and protein phosphorylation (1). Inactive PKA is a heterotetramer composed of a regulatory subunit (R) dimer and a catalytic subunit (C) dimer. In this inactive state, the pseudosubstrate sequences on the R subunits block the active sites on the C subunits. Three C subunit isoforms (C-α, C-β, and C-γ) and two families of regulatory subunits (RI and RII) with distinct cAMP binding properties have been identified. The two R families exist in two isoforms, α and β (RI-α, RI-β, RII-α, and RII-β). Upon binding of cAMP to the R subunits, the autoinhibitory contact is eased and active monomeric C subunits are released. PKA shares substrate specificity with Akt (PKB) and PKC, which are characterized by an arginine at position -3 relative to the phosphorylated serine or threonine residue (2). Substrates that present this consensus sequence and have been shown to be phosphorylated by PKA are Bad (Ser155), CREB (Ser133), and GSK-3 (GSK-3α Ser21 and GSK-3β Ser9) (3-5). In addition, combined knock-down of PKA C-α and -β blocks cAMP-mediated phosphorylation of Raf (Ser43 and Ser259) (6). Autophosphorylation and phosphorylation by PDK-1 are two known mechanisms responsible for phosphorylation of the C subunit at Thr197 (7).

$305
50 tests
100 µl
This Cell Signaling Technology (CST) antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated antibody (p44/42 MAPK (Erk1/2) (137F5) Rabbit mAb #4695).
APPLICATIONS
REACTIVITY
Bovine, C. elegans, D. melanogaster, Dog, Hamster, Human, Mink, Monkey, Mouse, Pig, Rat, Zebrafish

Application Methods: Flow Cytometry

Background: Mitogen-activated protein kinases (MAPKs) are a widely conserved family of serine/threonine protein kinases involved in many cellular programs, such as cell proliferation, differentiation, motility, and death. The p44/42 MAPK (Erk1/2) signaling pathway can be activated in response to a diverse range of extracellular stimuli including mitogens, growth factors, and cytokines (1-3), and research investigators consider it an important target in the diagnosis and treatment of cancer (4). Upon stimulation, a sequential three-part protein kinase cascade is initiated, consisting of a MAP kinase kinase kinase (MAPKKK or MAP3K), a MAP kinase kinase (MAPKK or MAP2K), and a MAP kinase (MAPK). Multiple p44/42 MAP3Ks have been identified, including members of the Raf family, as well as Mos and Tpl2/COT. MEK1 and MEK2 are the primary MAPKKs in this pathway (5,6). MEK1 and MEK2 activate p44 and p42 through phosphorylation of activation loop residues Thr202/Tyr204 and Thr185/Tyr187, respectively. Several downstream targets of p44/42 have been identified, including p90RSK (7) and the transcription factor Elk-1 (8,9). p44/42 are negatively regulated by a family of dual-specificity (Thr/Tyr) MAPK phosphatases, known as DUSPs or MKPs (10), along with MEK inhibitors, such as U0126 and PD98059.

$108
250 PCR reactions
500 µl
SimpleChIP® Human NPM1 Intron 1 Primers contain a mix of forward and reverse PCR primers that are specific to intron 1 of the human nucleophosmin (NPM1) gene. These primers can be used to amplify DNA that has been isolated using chromatin immunoprecipitation (ChIP). Primers have been optimized for use in SYBR® Green quantitative real-time PCR and have been tested in conjunction with SimpleChIP® Enzymatic Chromatin IP Kits #9002 and #9003 and ChIP-validated antibodies from Cell Signaling Technology®. The NPM1 gene is aberrantly expressed in certain cancer types and is regulated by c-Myc.
REACTIVITY
Human

Background: The chromatin immunoprecipitation (ChIP) assay is a powerful and versatile technique used for probing protein-DNA interactions within the natural chromatin context of the cell (1,2). This assay can be used to either identify multiple proteins associated with a specific region of the genome or to identify the many regions of the genome bound by a particular protein (3-6). ChIP can be used to determine the specific order of recruitment of various proteins to a gene promoter or to "measure" the relative amount of a particular histone modification across an entire gene locus (3,4). In addition to histone proteins, the ChIP assay can be used to analyze binding of transcription factors and co-factors, DNA replication factors, and DNA repair proteins. When performing the ChIP assay, cells are first fixed with formaldehyde, a reversible protein-DNA cross-linking agent that "preserves" the protein-DNA interactions occurring in the cell (1,2). Cells are lysed and chromatin is harvested and fragmented using either sonication or enzymatic digestion. Fragmented chromatin is then immunoprecipitated with antibodies specific to a particular protein or histone modification. Any DNA sequences that are associated with the protein or histone modification of interest will co-precipitate as part of the cross-linked chromatin complex and the relative amount of that DNA sequence will be enriched by the immunoselection process. After immunoprecipitation, the protein-DNA cross-links are reversed and the DNA is purified. Standard PCR or quantitative real-time PCR are often used to measure the amount of enrichment of a particular DNA sequence by a protein-specific immunoprecipitation (1,2). Alternatively, the ChIP assay can be combined with genomic tiling micro-array (ChIP on chip) techniques, high throughput sequencing (ChIP-Seq), or cloning strategies, all of which allow for genome-wide analysis of protein-DNA interactions and histone modifications (5-8). SimpleChIP® primers have been optimized for amplification of ChIP-isolated DNA using real-time quantitative PCR and provide important positive and negative controls that can be used to confirm a successful ChIP experiment.