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Product listing: APC Antibody, UniProt ID P25054 #2504 to TRIF Antibody, UniProt ID Q8IUC6 #4596

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: The Adenomatous Polyposis Coli (APC) tumor suppressor gene is mutated in most familial and sporadic colorectal cancers and encodes a large cytoplasmic protein that is implicated in cell migration, cell adhesion, and proliferation (1). APC binds directly to microtubules and lack of APC leads to defective mitotic spindles and aneuploidy due to missegregation of chromosomes (2). APC is well characterized as a scaffolding protein, binds to β-catenin, and is involved in the regulation of its intracellular concentration. In the absence of a Wnt signal, GSK-3β phosphorylates all three members of the APC-β-catenin-axin complex and this phosphorylation of β-catenin creates a recognition site for ubiquitin, the signal for proteasome-mediated degradation. In the presence of a Wnt signal, dishevelled inactivates GSK-3β and β-catenin coordinates gene transcription of proteins important for the control of cell cycle progression and proliferation, such as cyclin D1 and c-Myc (3).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: Adenine nucleotide translocase 2 (ANT2/SLC25A5) is a member of the adenine nucleotide translocase family of mitochondrial inner membrane proteins that function differently in metabolic and apoptotic pathways (1). Research studies indicate that ANT2 expression in undifferentiated, proliferating cells correlates with the rate of glycolytic metabolism and may be an indicator of carcinogenesis (2). Suppression of ANT2/SLC25A5 expression by specific RNA interference in human breast cancer cells promotes apoptosis and inhibits tumor cell growth (2), which suggests a cytoprotective role of ANT2/SLC25A5 (1,3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: Actin proteins are major components of the eukaryotic cytoskeleton. At least six vertebrate actin isoforms have been identified. The cytoplasmic β- and γ-actin proteins are referred to as “non-muscle” actin proteins as they are predominantly expressed in non-muscle cells where they control cell structure and motility (1). The α-cardiac and α-skeletal actin proteins are expressed in striated cardiac and skeletal muscles, respectively. The smooth muscle α-actin and γ-actin proteins are found primarily in vascular smooth muscle and enteric smooth muscle, respectively. The α-smooth muscle actin (ACTA2) is also known as aortic smooth muscle actin. These actin isoforms regulate the contractile potential of muscle cells (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Members of the Toll-like receptor (TLR) family, named for the closely related Toll receptor in Drosophila, play a pivotal role in innate immune responses (1-4). TLRs recognize conserved motifs found in various pathogens and mediate defense responses (5-7). Triggering of the TLR pathway leads to the activation of NF-κB and subsequent regulation of immune and inflammatory genes (4). The TLRs and members of the IL-1 receptor family share a conserved stretch of approximately 200 amino acids known as the Toll/Interleukin-1 receptor (TIR) domain (1). Upon activation, TLRs associate with a number of cytoplasmic adaptor proteins containing TIR domains, including myeloid differentiation factor 88 (MyD88), MyD88-adaptor-like/TIR-associated protein (MAL/TIRAP), Toll-receptor-associated activator of interferon (TRIF), and Toll-receptor-associated molecule (TRAM) (8-10). This association leads to the recruitment and activation of IRAK1 and IRAK4, which form a complex with TRAF6 to activate TAK1 and IKK (8,11-14). Activation of IKK leads to the degradation of IκB, which normally maintains NF-κB in an inactive state by sequestering it in the cytoplasm.

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Autophagy is a catabolic process for the autophagosomic-lysosomal degradation of bulk cytoplasmic contents (1,2). Autophagy is generally activated by conditions of nutrient deprivation but is also associated with a number of physiological processes including development, differentiation, neurodegeneration, infection and cancer (3). The molecular machinery of autophagy was largely discovered in yeast and is directed by a number of autophagy-related (Atg) genes. These proteins are involved in the formation of autophagosomes, cytoplasmic vacuoles that are delivered to lysosomes for degradation. The class III type phosphoinositide 3-kinase (PI3K) Vps34 regulates vacuolar trafficking and autophagy (4,5). Multiple proteins associate with Vsp34, including p105/Vsp15, Beclin-1, UVRAG, Atg14, and Rubicon, to determine Vsp34 function (6-12). Atg14 and Rubicon were identified based on their ability to bind to Beclin-1 and participate in unique complexes with opposing functions (9-12). Rubicon, which localizes to the endosome and lysosome, inhibits Vps34 lipid kinase activity; knockdown of Rubicon enhances autophagy and endocytic trafficking (11,12). In contrast, Atg14 localizes to autophagosomes, isolation membranes and ER, and can enhance Vps34 activity. Knockdown of Atg14 inhibits starvation-induced autophagy (11,12).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Tenascin C is a large hexameric extracellular matrix glycoprotein that exhibits de-adhesive effects on cell-matrix interaction, enhancing cell proliferation and motility in most cell types. It is highly expressed in remodeling tissues during embryonic development and under pathological conditions in adults, and research studies have shown markedly increased expression in cancerous tissues (1,2). Tenascin C has been implicated in a variety of cellular processes relevant to atherosclerosis, including cell proliferation, migration, and apoptosis. Expression of Tenascin C is tightly controlled in adults and is upregulated in tissues undergoing wound healing (3). In development, the expression of Tenascin C is known to be associated with epithelial-mesenchymal transition (EMT) events including gastrulation and formation of the neural crest, endocardial cushion, and secondary palate (1). Investigators have shown that Tenascin C is a key determinant of the tumor stroma and that it is involved in the initiation of tumorigenesis and progression to metastasis (2). Immature and mature astrocytes, radial glial cells, Schwann cells, and a subset of neurons express Tenascin C. Upon CNS trauma or exposure of neurons to excitotoxic agents, Tenascin C expression is upregulated by glial cells. Research studies have shown that Tenascin C is involved in guidance of migrating axons and neurons, synaptic plasticity, and neuronal regeneration, promoting spinal cord regeneration after injury (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: The prohibitins PHB1 and PHB2 are highly conserved, multifunctional proteins present in eukaryotic nuclear and mitochondrial compartments (1). Prohibitin-2 (PHB2, REA) was originally identified as an estrogen receptor-specific coregulator. PHB2 directly interacts with hormone-bound estrogen receptor and represses its transcriptional activity through competitive inhibition of Src-1 coactivation of the estrogen receptor (2,3). Together with COUP transcription factors, PHB2 interacts with histone deacetylases HDAC1 and HDAC5 to mediate transcriptional regulation by the estrogen receptor through coupling the deacetylase to the transcription activation complex (4). Prohibitin PHB1/PHB2 heterodimers form large ring complexes on the mitochondrial membrane (5) and act as chaperones to stabilize mitochondrial proteins, such as OPA1 and Hax1, to support mitochondrial morphogenesis and protect against apoptosis (6-8).

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

Application Methods: Western Blotting

Background: Glucose-6-phosphate dehydrogenase (G6PD) catalyses the first, and rate-limiting, step of the pentose phosphate pathway (1). The NADPH generated from this reaction is essential to protect cells from oxidative stress (1). Research studies have shown that p53 interacts with G6PD and inhibits its activity, therefore suppressing glucose consumption through the pentose phosphate pathway (2). In cancer cells with p53 mutations, the increased glucose consumption is directed towards increased biosynthesis, which is critical for cancer cell proliferation (2).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: Dishevelled (Dsh) proteins are important intermediates of Wnt signaling pathways. Dsh inhibits glycogen synthase kinase-3β promoting β-catenin stabilization. Dsh proteins also participate in the planar cell polarity pathway by acting through JNK (1,2). There are three Dsh homologs, Dvl1, Dvl2 and Dvl3 in mammals. Upon treatment with Wnt proteins, Dvls become hyperphosphorylated (3) and accumulate in the nucleus (4). Dvl proteins also associate with actin fibers and cytoplasmic vesicular membranes (5) and mediate endocytosis of the Fzd receptor after Wnt protein stimulation (6). Overexpression of Dvl has been reported in certain cancers (7,8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: AMPA- (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid), kainate-, and NMDA- (N-methyl-D-aspartate) receptors are the three main families of ionotropic glutamate-gated ion channels. AMPA receptors (AMPARs) are comprised of four subunits (GluR 1-4), which assemble as homo- or hetero-tetramers to mediate the majority of fast excitatory transmissions in the central nervous system. AMPARs are implicated in synapse formation, stabilization, and plasticity (1). In contrast to GluR 2-containing AMPARs, AMPARs that lack GluR 2 are permeable to calcium (2). Post-transcriptional modifications (alternative splicing, nuclear RNA editing) and post-translational modifications (glycosylation, phosphorylation) result in a very large number of permutations, fine-tuning the kinetic properties of AMPARs. Research studies have implicated activity changes in AMPARs in a variety of diseases including Alzheimer’s, amyotrophic lateral sclerosis (ALS), stroke, and epilepsy (1).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: The X-linked RNA binding motif protein (RBMX, hnRNP G) is a multi-functional protein that is part of a heterogeneous nuclear ribonucleoprotein complex (1,2). This widely expressed protein is involved in the control of pre-mRNA splicing as part of the spliceosome. RBMX is important for the alternative splicing of many pre-mRNAs, including those that encode for dystrophin, tropomyosin, and survival motor neuron protein (SMN) in skeletal muscle and cardiac muscle (3,4). The RBMX protein is essential for the maintenance of proper sister chromatid cohesion prior to sister chromosome segregation during mitosis (5). Research studies show that RBMX accumulates at sites of DNA damage and that the presence of RBMX is required for homologous recombination repair (6).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry)

Background: SSEA4 (stage-specific embryonic antigen 4) is a glycolipid carbohydrate epitope expressed on the surface of human teratocarcinoma stem cells, human embryonic germ cells, and human embryonic stem cells (1). Expression of human SSEA4 decreases following differentiation of human embryonal carcinoma cells. Expression of the SSEA4 antigen is absent in murine pluripotent cells, but increases following differentiation (1,2).

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

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

Background: Ubiquitinating enzymes (UBEs) catalyze protein ubiquitination, a reversible process countered by deubiquitinating enzyme (DUB) action (1,2). Five DUB subfamilies are recognized, including the USP, UCH, OTU, MJD, and JAMM enzymes. USP10 possesses amino acid sequences that match the consensus cysteine and histidine boxes representative of the USP family of deubiquitinating enzymes. At the posttranslational level, USP10 appears to be regulated through both protein-protein interactions and phosphorylation. Indeed, interaction of USP10 with Ras-GAP SH3 domain binding protein (G3BP) has been found to inhibit its ability to catalyze the disassembly of ubiquitin chains (3). Furthermore, ATM-mediated phosphorylation of USP10 at Thr42 and Ser337 was shown to promote USP10 stabilization and redistribution from the cytoplasm to the nucleus, where it functions in p53 deubiquitination, stabilization, and activation in response to genotoxic stress (4). Recently, it was shown that USP10 works in concert with USP13 and Vps34 complexes. USP10, along with USP13, appears to deubiquitinate Vps34 complexes to regulate the levels of this class III PI3K. Beclin-1, another component of these complexes, functions to regulate the stability of USP13, which can deubiquitinate and stabilize the levels of USP10. Therefore, Beclin-1, can indirectly regulate p53 stability by controlling the DUB activity of USP10 (5). USP10 also functions in the endosomal compartment, where it has been shown to deubiquitinate CFTR in order to enhance its endocytic recycling and cell surface expression (6,7).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: Notch signaling is activated upon engagement of the Notch receptor with its ligands, the DSL (Delta, Serrate, Lag2) proteins of single-pass type I membrane proteins. The DSL proteins contain multiple EGF-like repeats and a DSL domain that is required for binding to Notch (1,2). Five DSL proteins have been identified in mammals: Jagged1, Jagged2, Delta-like (DLL) 1, 3 and 4 (3). Ligand binding to the Notch receptor results in two sequential proteolytic cleavages of the receptor by the ADAM protease and the γ-secretase complex. The intracellular domain of Notch is released and then translocates to the nucleus where it activates transcription. Notch ligands may also be processed in a way similar to Notch, suggesting a bi-directional signaling through receptor-ligand interactions (4-6).

The ULK1 Antibody Sampler Kit provides an economical way to investigate ULK1 signaling. The kit contains enough primary antibody to perform two western blots with each primary antibody.

Background: Two related serine/threonine kinases, UNC-51-like kinase 1 and 2 (ULK1, ULK2), were discovered as mammalian homologs of the C. elegans gene UNC-51 in which mutants exhibited abnormal axonal extension and growth (1-4). Both proteins are widely expressed and contain an amino-terminal kinase domain followed by a central proline/serine rich domain and a highly conserved carboxy-terminal domain. The roles of ULK1 and ULK2 in axon growth have been linked to studies showing that the kinases are localized to neuronal growth cones and are involved in endocytosis of critical growth factors, such as NGF (5). Yeast two-hybrid studies found ULK1/2 associated with modulators of the endocytic pathway, SynGAP and syntenin (6). Structural similarity of ULK1/2 has also been recognized with the yeast autophagy protein Atg1/Apg1 (7). Knockdown experiments using siRNA demonstrated that ULK1 is essential for autophagy (8), a catabolic process for the degradation of bulk cytoplasmic contents (9,10). It appears that Atg1/ULK1 can act as a convergence point for multiple signals that control autophagy (11), and can bind to several autophagy-related (Atg) proteins, regulating phosphorylation states and protein trafficking (12-16).

The Angiogenesis Antibody Sampler Kit provides an economical means to investigate the angiogenic pathway downstream of VEGFR2. The kit contains enough primary antibody to perform two western blots per primary antibody.
$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-Syk (Tyr525/526) (C87C1) Rabbit mAb #2710.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Syk is a protein tyrosine kinase that plays an important role in intracellular signal transduction in hematopoietic cells (1-3). Syk interacts with immunoreceptor tyrosine-based activation motifs (ITAMs) located in the cytoplasmic domains of immune receptors (4). It couples the activated immunoreceptors to downstream signaling events that mediate diverse cellular responses, including proliferation, differentiation, and phagocytosis (4). There is also evidence of a role for Syk in nonimmune cells and investigators have indicated that Syk is a potential tumor suppressor in human breast carcinomas (5). Tyr323 is a negative regulatory phosphorylation site within the SH2-kinase linker region in Syk. Phosphorylation at Tyr323 provides a direct binding site for the TKB domain of Cbl (6,7). Tyr352 of Syk is involved in the association of PLCγ1 (8). Tyr525 and Tyr526 are located in the activation loop of the Syk kinase domain; phosphorylation at Tyr525/526 of human Syk (equivalent to Tyr519/520 of mouse Syk) is essential for Syk function (9).

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-p38 MAPK (Thr180/Tyr182) (3D7) Rabbit mAb #9215.
APPLICATIONS
REACTIVITY
D. melanogaster, Human, Monkey, Mouse, Pig, Rat, S. cerevisiae

Application Methods: Flow Cytometry

Background: p38 MAP kinase (MAPK), also called RK (1) or CSBP (2), is the mammalian orthologue of the yeast HOG kinase that participates in a signaling cascade controlling cellular responses to cytokines and stress (1-4). Four isoforms of p38 MAPK, p38α, β, γ (also known as Erk6 or SAPK3), and δ (also known as SAPK4) have been identified. Similar to the SAPK/JNK pathway, p38 MAPK is activated by a variety of cellular stresses including osmotic shock, inflammatory cytokines, lipopolysaccharide (LPS), UV light, and growth factors (1-5). MKK3, MKK6, and SEK activate p38 MAPK by phosphorylation at Thr180 and Tyr182. Activated p38 MAPK has been shown to phosphorylate and activate MAPKAP kinase 2 (3) and to phosphorylate the transcription factors ATF-2 (5), Max (6), and MEF2 (5-8). SB203580 (4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-imidazole) is a selective inhibitor of p38 MAPK. This compound inhibits the activation of MAPKAPK-2 by p38 MAPK and subsequent phosphorylation of HSP27 (9). SB203580 inhibits p38 MAPK catalytic activity by binding to the ATP-binding pocket, but does not inhibit phosphorylation of p38 MAPK by upstream kinases (10).

$303
100 µl
APPLICATIONS
REACTIVITY
All Species Expected, Human, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Peptide ELISA (DELFIA), Western Blotting

Background: The MAPK and CDK families of serine/threonine protein kinases play important roles in cell signaling and cell cycle control. These kinases phosphorylate threonine or serine followed by a proline residue (1-6). To facilitate the study and discovery of new MAPK and CDK substrates, Cell Signaling Technology has developed antibodies that bind to phospho-threonine or phospho-serine followed by proline.

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Tau is a heterogeneous microtubule-associated protein that promotes and stabilizes microtubule assembly, especially in axons. Six isoforms with different amino-terminal inserts and different numbers of tandem repeats near the carboxy terminus have been identified, and tau is hyperphosphorylated at approximately 25 sites by Erk, GSK-3, and CDK5 (1,2). Phosphorylation decreases the ability of tau to bind to microtubules. Neurofibrillary tangles are a major hallmark of Alzheimer's disease; these tangles are bundles of paired helical filaments composed of hyperphosphorylated tau. In particular, phosphorylation at Ser396 by GSK-3 or CDK5 destabilizes microtubules. Furthermore, research studies have shown that inclusions of tau are found in a number of other neurodegenerative diseases, collectively known as tauopathies (1,3).

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

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

Background: MKK3 and MKK6 are two closely related dual-specificity protein kinases that activate p38 MAP kinase (1-5). MKK3 and MKK6 both phosphorylate and activate p38 MAP kinase at its activation site, Thr-Gly-Tyr, but do not phosphorylate or activate Erk1/2 or SAPK/JNK. Phosphorylation of p38 MAP kinase dramatically stimulates its ability to phosphorylate protein substrates such as ATF-2 and Elk-1. MKK3 and MKK6 are both activated by different forms of cellular stress and inflammatory cytokines (4,5). Activation of MKK3 and MKK6 occurs through phosphorylation at Ser189 and Thr222 on MKK3 (2) and Ser207 and Thr211 on MKK6 (4,5).

$293
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Western Blotting

Background: Interleukin-10 (IL-10) is an anti-inflammatory cytokine that is produced by T cells, NK cells, and macrophages (1,2). IL-10 initiates signal transduction by binding to a cell surface receptor complex consisting of IL-10 RI and IL-10 RII (1), leading to the activation of Jak1 and Tyk2 and phosphorylation of Stat3 (1,3). The anti-inflammatory activity of IL-10 is due to its ability to block signaling through other cytokine receptors, notably IFN-γ receptor, by upregulating expression of SOCS1 (1,3). In addition, IL-10 promotes T cell tolerance by inhibiting tyrosine phosphorylation of CD28 (4,5). IL-10 is an important negative regulator of the immune response, which allows for maintenance of pregnancy (1). In contrast, increased IL-10 levels contribute to persistent Leishmania major infections (6).

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

Application Methods: Chromatin IP, Chromatin IP-seq, Flow Cytometry, Immunoprecipitation, Western Blotting

Background: Helios (Ikaros family zinc finger 2, IZKF2) is an Ikaros family transcription factor composed of several zinc fingers that mediate DNA binding and homodimerization or heterodimerization with other Ikaros family proteins (1,2). In the hematopoietic system, Helios expression is restricted to T cells and early hematopoietic progenitors (1,2). In regulatory T cells, expression of Helios contributes to an anergic phenotype by binding to the IL-2 promoter and suppressing IL-2 transcription (3). In addition, alteration of the corresponding Helios gene IZKF2 is one hallmark of low-hypodiploid acute lymphoblastic leukemia (4).

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

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

Background: Translation initiation requires a set of factors to facilitate the association of the 40S ribosomal subunit with mRNA. The eIF4F complex, consisting of eIF4E, eIF4A, and eIF4G, binds to the 5' cap structure of mRNA. eIF4F and eIF4B unwind the secondary structure of mRNA at its 5' untranslated region. The 40S ribosomal subunit, along with some initiation factors including eIF3, then binds to the 5' mRNA cap and searches along the mRNA for the initiation codon. eIF3 is a large translation initiation complex with 10 to 13 different subunits. eIF3A, eIF3B, eIF3C, eIF3E, eIF3F, and eIF3H are the core subunits critical for the function of this complex. eIF3 physically interacts with eIF4G, which may be responsible for the association of the 40S ribosomal subunit with mRNA (1). eIF3 also stabilizes the binding of Met-tRNAf.eIF2.GTP to the 40S ribosomal subunit and helps keep the integrity of the resulting complex upon addition of the 60S ribosomal subunit (2). Studies have shown that mTOR interacts with eIF3 directly (3,4). When cells are stimulated by hormones or mitogenic signals, mTOR binds to the eIF3 complex and phosphorylates S6K1 (3). This process results in the dissociation of S6K1 from eIF3 and S6K1 activation. The activated S6K1 then phosphorylates its downstream targets including ribosomal protein S6 and eIF4B, resulting in stimulation of translation. Further findings demonstrated that activated mTOR signaling induces the association of eIF3 with eIF4G upon stimulation with insulin (3).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Chromatin IP, Western Blotting

Background: The Fos family of nuclear oncogenes includes c-Fos, FosB, Fos-related antigen 1 (FRA1), and Fos-related antigen 2 (FRA2) (1). While most Fos proteins exist as a single isoform, the FosB protein exists as two isoforms: full-length FosB and a shorter form, FosB2 (Delta FosB), which lacks the carboxy-terminal 101 amino acids (1-3). The expression of Fos proteins is rapidly and transiently induced by a variety of extracellular stimuli including growth factors, cytokines, neurotransmitters, polypeptide hormones, and stress. Fos proteins dimerize with Jun proteins (c-Jun, JunB, and JunD) to form Activator Protein-1 (AP-1), a transcription factor that binds to TRE/AP-1 elements and activates transcription. Fos and Jun proteins contain the leucine-zipper motif that mediates dimerization and an adjacent basic domain that binds to DNA. The various Fos/Jun heterodimers differ in their ability to transactivate AP-1 dependent genes. In addition to increased expression, phosphorylation of Fos proteins by Erk kinases in response to extracellular stimuli may further increase transcriptional activity (4-6). Phosphorylation of c-Fos at Ser32 and Thr232 by Erk5 increases protein stability and nuclear localization (5). Phosphorylation of FRA1 at Ser252 and Ser265 by Erk1/2 increases protein stability and leads to overexpression of FRA1 in cancer cells (6). Following growth factor stimulation, expression of FosB and c-Fos in quiescent fibroblasts is immediate, but very short-lived, with protein levels dissipating after several hours (7). FRA1 and FRA2 expression persists longer, and appreciable levels can be detected in asynchronously growing cells (8). Deregulated expression of c-Fos, FosB, or FRA2 can result in neoplastic cellular transformation; however, Delta FosB lacks the ability to transform cells (2,3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

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

Background: The NFAT (nuclear factor of activated T cells) family of proteins consists of NFAT1 (NFATc2 or NFATp), NFAT2 (NFATc1 or NFATc), NFAT3 (NFATc4), and NFAT4 (NFATc3 or NFATx). All members of this family are transcription factors with a Rel homology domain and regulate gene transcription in concert with AP-1 (Jun/Fos) to orchestrate an effective immune response (1,2). NFAT proteins are predominantly expressed in cells of the immune system, but are also expressed in skeletal muscle, keratinocytes, and adipocytes, regulating cell differentiation programs in these cells (3). In resting cells, NFAT proteins are heavily phosphorylated and localized in the cytoplasm. Increased intracellular calcium concentrations activate the calcium/calmodulin-dependent serine phosphatase calcineurin, which dephosphorylates NFAT proteins, resulting in their subsequent translocation to the nucleus (2). Termination of NFAT signaling occurs upon declining calcium concentrations and phosphorylation of NFAT by kinases such as GSK-3 or CK1 (3,4). Cyclosporin A and FK506 are immunosuppressive drugs that inhibit calcineurin and thus retain NFAT proteins in the cytoplasm (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: Salt-inducible kinase 1 (SIK1) was originally identified as a serine/threonine kinase from adrenocortical tissues of rats on a high salt diet (1). SIK1 is a SNF1/AMPK family kinase capable of autophosphorylation (1). SIK2 is an isoform of SIK1 and is specifically expressed in adipose tissues where it is induced during adipocyte differentiation (2). Studies suggest that SIK2 can phosphorylate human insulin receptor substrate (IRS-1) at Ser794. Along with evidence that SIK2 expression and activity are increased in white adipocytes of diabetic mice, this finding suggests a possible role for SIK2 in regulating insulin signaling in adipocytes and in the development of insulin resistance (2,3). Insulin triggers Akt2-mediated phosphorylation of SIK2 at Ser358 and the resultant kinase activation during post-fasting feeding (4). The activated SIK2 then induces the phosphorylation of Torc2 at Ser171 resulting in translocation of this transcriptional coactivator from the nucleus to cytoplasm where it is degraded through the ubiquitin pathway, leading to inhibition of gluconeogenic gene expression (4).

$122
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

Application Methods: Western Blotting

Background: The Forkhead family of transcription factors is involved in tumorigenesis of rhabdomyosarcoma and acute leukemias (1-3). Within the family, three members (FoxO1, FoxO4, and FoxO3a) have sequence similarity to the nematode orthologue DAF-16, which mediates signaling via a pathway involving IGFR1, PI3K, and Akt (4-6). Active forkhead members act as tumor suppressors by promoting cell cycle arrest and apoptosis. Increased expression of any FoxO member results in the activation of the cell cycle inhibitor p27 Kip1. Forkhead transcription factors also play a part in TGF-β-mediated upregulation of p21 Cip1, a process negatively regulated through PI3K (7). Increased proliferation results when forkhead transcription factors are inactivated through phosphorylation by Akt at Thr24, Ser256, and Ser319, which results in nuclear export and inhibition of transcription factor activity (8). Forkhead transcription factors can also be inhibited by the deacetylase sirtuin (SirT1) (9).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Casein Kinase I (CK1 or CKI) is the name given to a family of kinases consisting of multiple isoforms (α, α', β, γ1-3, δ, and ε) with a conserved N-terminal kinase domain and a variable C-terminal sequence that determines subcellular localization and regulates enzyme activity (1-3). Indeed, multiple inhibitory autophosphorylation sites have been identified near the C terminus of CK1ε (3). This ubiquitously expressed family of protein kinases has been implicated in multiple processes including DNA repair, cell morphology, and Wnt signaling (4). Perhaps the best understood role of CK1 is to provide the priming phosphorylation of β-catenin at Ser45 to produce the consensus GSK-3 substrate motif (S/T-X-X-X-pS) (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Members of the Toll-like receptor (TLR) family, named for the closely related Toll receptor in Drosophila, play a pivotal role in innate immune responses (1-4). TLRs recognize conserved motifs found in various pathogens and mediate defense responses (5-7). Triggering of the TLR pathway leads to the activation of NF-κB and subsequent regulation of immune and inflammatory genes (4). The TLRs and members of the IL-1 receptor family share a conserved stretch of approximately 200 amino acids known as the Toll/Interleukin-1 receptor (TIR) domain (1). Upon activation, TLRs associate with a number of cytoplasmic adaptor proteins containing TIR domains, including myeloid differentiation factor 88 (MyD88), MyD88-adaptor-like/TIR-associated protein (MAL/TIRAP), Toll-receptor-associated activator of interferon (TRIF), and Toll-receptor-associated molecule (TRAM) (8-10). This association leads to the recruitment and activation of IRAK1 and IRAK4, which form a complex with TRAF6 to activate TAK1 and IKK (8,11-14). Activation of IKK leads to the degradation of IκB, which normally maintains NF-κB in an inactive state by sequestering it in the cytoplasm.