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Product listing: PD-1 (D7D5W) XP® Rabbit mAb (Mouse Specific) (Alexa Fluor® 647 Conjugate), UniProt ID Q02242 #61237 to FoxP3 (D2W8E™) Rabbit mAb (IHC Specific), UniProt ID Q9BZS1 #98377

$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 647 fluorescent dye and tested in-house for direct immunofluorescent analysis in mouse cells and tissues. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated PD-1 (D7D5W) XP® Rabbit mAb (Mouse Specific) #84651.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Immunofluorescence (Frozen), Immunofluorescence (Immunocytochemistry)

Background: The programmed cell death 1 protein (PD-1, PDCD1, CD279) is a member of the CD28 family of immunoreceptors that regulate T cell activation and immune responses (1-3). The PD-1 protein contains an extracellular Ig V domain, a transmembrane domain, and a cytoplasmic tail that includes an immunoreceptor tyrosine-based inhibitory motif (ITIM) and an immunoreceptor tyrosine-based switch motif (ITSM). PD-1 is activated by the cell surface ligands PD-L1 and PD-L2 (4). Upon activation, PD-1 ITIM and ITSM phosphorylation leads to the recruitment of the protein tyrosine phosphatases SHP-1 and SHP-2, which suppress TCR signaling (5-7). In addition to activated T-cells, PD-1 is expressed in activated B-cells and monocytes, although its function in these cell types has not been fully characterized (8). The PD-1 pathway plays an important role in immune tolerance (3); however, research studies show that cancer cells often adopt this pathway to escape immune surveillance (9). Consequently, blockade of PD-1 and its ligands is proving to be a sound strategy for neoplastic intervention (10).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: The triggering receptor expressed on myeloid cells 2 (TREM2) protein is an innate immune receptor that is expressed on the cell surface of microglia, macrophages, osteoclasts, and immature dendritic cells (1). The TREM2 receptor is a single-pass type I membrane glycoprotein that consists of an extracellular immunoglobulin-like domain, a transmembrane domain, and a cytoplasmic tail. TREM2 interacts with the tyrosine kinase-binding protein DAP12 to form a receptor-signaling complex (2). The TREM2 protein plays a role in innate immunity and a rare functional variant (R47H) of TREM2 is associated with the late-onset risk of Alzheimer’s disease (1,3). Research studies using mouse models of Alzheimer’s disease indicate that deficiency and haploinsufficiency of TREM2 can lead to increased β-amyloid (Aβ) accumulation as a result of dysfunctional microglia response (4). These results agree with the distribution of TREM2 in human brain regions (e.g., white matter, the hippocampus, and neocortex) that are involved in Alzheimer's disease pathology (2). In addition, amyloid plaque formation induces expression of TREM2 and amyloid phagocytosis (5). Loss-of-function mutations in the corresponding TREM2 or DAP12 genes can result in Nasu-Hakola disease, a rare form of progressive presenile dementia that results from polycystic osseous lesions (6). TREM2 membrane shedding occurs by cleavage at the extracellular site between H157/S158 generating an N-terminal shedded fragment and a membrane bound C-terminal fragment (7, 8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Western Blotting

Background: RALY is a member of the large family of heterogeneous nuclear ribonucleoproteins (hnRNPs). RALY was initially discovered in lethal yellow mice, a condition where heterozygotes display an all yellow coat, obesity, diabetes, and tumors. In this condition, mRNA to the 5’ untranslated region of RALY fuses to the agouti transcript (1,2). RALY binds to U-rich elements in coding and non-coding mRNAs undergoing translation (3). RALY has been implicated certain cancer types, as it can control transcriptional regulation and splicing of E2F1 and PRMT1 mRNAs (4,5).

Premium Methanol from Cell Signaling Technology is submicron filtered and 99.9% pure. It is recommended for use as a fixative or permeabilization agent in immunofluorescence and flow cytometry assays.Important: Not all CST primary antibodies require samples to be prepared with methanol fixation or permeabilization prior to immunostaining. Please refer to the antibody datasheet to determine if methanol is recommended.
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Chromatin IP, Western Blotting

Background: Hypoxia-inducible factor (HIF) is essential for the cellular response to hypoxia (1,2). Under normoxia conditions, the α subunit of HIF is ubiquitinated by von Hippel-Lindau (VHL) protein and is degraded in the ubiquitin/proteasome pathway (1,2). Hypoxia inhibits the degradation of the α subunit, which leads to its stabilization (1,2). HIF, in turn, regulates the transcription of a variety of genes that respond to hypoxia conditions (1,2). There are several isoforms of the HIF α subunit (2). Studies have found that HIF-1α and HIF-2α expression is increased in some human cancers (2). HIF-1α has both pro- and anti-proliferative activities, whereas HIF-2α does not possess anti-proliferative activity (2). Therefore, HIF-2α likely plays an important role in tumorigenesis (2,3).

The BAF Complex Antibody Sampler Kit II provides an economical means of detecting levels of various BAF complex components. The kit contains enough primary antibodies to perform at least two western blot experiments.
$42
50 ml
FastScan™ ELISA Cell Extraction Buffer (5X) is used with FastScan™ ELISA Cell Extraction Enhancer Solution (50X) #25243 (not supplied) to prepare and dilute cell extracts for use in FastScan™ ELISA Kits.
Senescence Associated Secretory Phenotype (SASP) Antibody Sampler Kit provides an economical means of detecting multiple components of the SASP. The kit includes enough antibody to perform two western blot experiments with each primary antibody.

Background: Senescence is characterized by stable stress-induced proliferative arrest and resistance to mitogenic stimuli, as well as the secretion of proteins such as cytokines, growth factors and proteases. These secreted proteins comprise the senescence-associated secretory phenotype (SASP). Senescent cells are thought to accumulate as an organism ages, and contribute to age-related diseases, including cancer, through promotion of inflammation and disruption of normal cellular function (1,2). The composition of the SASP varies, and SASP components can be either beneficial or deleterious in human disease, depending on the context (3).Senescence Associated Secretory Phenotype (SASP) Antibody Sampler Kit provides a collection of antibodies to various SASP components, including TNF-alpha, interleukin-6 (IL-6), the multifunctional cytokine IL-1beta, the chemokines CXCL10, RANTES/CCL5 and MCP-1, the matrix metalloprotease MMP3, and the serine-protease inhibitor PAI-1.

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Transcription factor EB (TFEB) is a member of the Myc-related, bHLH leucine-zipper family of transcription factors that drives the expression of a network of genes known as the Coordinated Lysosomal Expression and Regulation (CLEAR) network (1,2). TFEB specifically recognizes and binds regulatory sequences within the CLEAR box (GTCACGTGAC) of lysosomal and autophagy genes, resulting in the up-regulated expression of genes involved in lysosome biogenesis and function, and regulation of autophagy (1,2). TFEB is activated in response to nutrient deprivation, stimulating translocation to the nucleus where it forms homo- or heterooligomers with other members of the microphthalmia transcription factor (MiTF) subfamily and resulting in up-regulation of autophagosomes and lysosomes (3-5). Recently, it has been shown that TFEB is a component of mammalian target of rapamycin (mTOR) complex 1 (mTORC1), which regulates the phosphorylation and nuclear translocation of TFEB in response to cellular starvation and stress (6-9). During normal growth conditions, TFEB is phosphorylated at Ser211 in an mTORC1-dependent manner. Phosphorylation promotes association of TFEB with 14-3-3 family proteins and retention in the cytosol. Inhibition of mTORC1 results in a loss of TFEB phosphorylation, dissociation of the TFEB/14-3-3 complex, and rapid transport of TFEB to the nucleus where it increases transcription of CLEAR and autophagy genes (10). TFEB has also been shown to be activated in a nutrient-dependent manner by p42 MAP kinase (Erk2). TFEB is phosphorylated at Ser142 by Erk2 in response to nutrient deprivation, resulting in nuclear localization and activation, and indicating that pathways other than mTOR contribute to nutrient sensing via TFEB (3).

$63
125 ml
ELISA Wash Buffer (20X) is specifically formulated for use with both FastScan™ and PathScan® ELISA Kits. It is the recommended buffer to be used for all wash steps within the protocols for both kits.
$269
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: IHC-Leica® Bond™, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Western Blotting

Background: CD80 (B7-1, BB1) and CD86 (B7-2, B70) are members of the B7 family of cell surface ligands that regulate T cell activation and immune responses. CD80 is expressed on activated antigen presenting cells, including dendritic cells, B cells, monocytes, and macrophages. CD86 is expressed on resting monocytes, dendritic cells, activated B lymphocytes, and can be further upregulated in the presence of inflammation (1-3). CD80 and CD86 are ligands for CD28, which functions as a T cell costimulatory receptor. Interaction of CD28 with CD80 or CD86 provides the second signal required for naïve T cell activation, T cell proliferation, and acquisition of effector functions (3-7). Alternatively, CD80 and CD86 also act as ligands to CTLA-4, which results in the downregulation of T cell activity (3,7-9).

$199
100 µg
This Cell Signaling Technology antibody is conjugated to redFluor™ 710 and tested in-house for direct flow cytometric analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: Major histocompatibility complex class II (MHC class II) molecules are heterodimeric, transmembrane glycoproteins expressed on the surface of antigen-presenting cells such as macrophages, dendritic cells, and B cells. Expression can also be induced on other cell types through interferon-γ signaling (1). Prior to being displayed on the cell membrane, MHC class II molecules are loaded with exogenous peptide antigens approximately 15-24 amino acids in length that were derived from endocytosed extracellular proteins digested in the lysosome (2). Antigen-presentation through MHC class II is required for T cell activation during the immune response to extracellular pathogens (2). In humans, the MHC class II protein complex is encoded by the human leukocyte antigen gene complex (HLA). HLAs corresponding to MHC class II are HLA-DP, HLA-DM, HLA-DOA, HLA-DOB, HLA-DQ, and HLA-DR (3).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: TBK1 (TANK-binding kinase 1)/NAK (NF-κB activating kinase) is an IκB kinase (IKK)-activating kinase and can activate IKK through direct phosphorylation (1). TBK1 was identified through association with the TRAF binding protein, TANK, and found to function upstream of NIK and IKK in the activation of NF-κB (2). TBK1 induces IκB degradation and NF-κB activity through IKKβ. TBK1 may mediate IKK and NF-κB activation in response to growth factors that stimulate PKCε activity (1). TBK1 plays a pivotal role in the activation of IRF3 in the innate immune response (3).

$303
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Western Blotting

Background: The receptor-interacting protein (RIP) family of serine-threonine kinases (RIP, RIP2, RIP3, and RIP4) are important regulators of cellular stress that trigger pro-survival and inflammatory responses through the activation of NF-κB, as well as pro-apoptotic pathways (1). In addition to the kinase domain, RIP contains a death domain responsible for interaction with the death domain receptor Fas and recruitment to TNF-R1 through interaction with TRADD (2,3). RIP-deficient cells show a failure in TNF-mediated NF-κB activation, making the cells more sensitive to apoptosis (4,5). RIP also interacts with TNF-receptor-associated factors (TRAFs) and can recruit IKKs to the TNF-R1 signaling complex via interaction with NEMO, leading to IκB phosphorylation and degradation (6,7). Overexpression of RIP induces both NF-κB activation and apoptosis (2,3). Caspase-8-dependent cleavage of the RIP death domain can trigger the apoptotic activity of RIP (8).

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

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

Background: Rab5 is a member of the Ras superfamily of small Rab GTPases. Rab5 is localized at the plasma membrane and early endosomes and functions as a key regulator of vesicular trafficking during early endocytosis (1). The conformational change between Rab5 GTP/GDP states is essential for its biological function as a rate limiting regulator at multiple steps during endocytosis (1,2). Rab5 exerts its function by interacting with several Rab5-specific effectors (1-3). These proteins form complexes with Rab5 on a specialized Rab domain of the endosome and promote recycling of Rab5-cargo targets between endosome and the plasma membrane.

$305
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 647 fluorescent dye and tested in-house for direct flow cytometric analysis in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated p16 INK4A (D7C1M) Rabbit mAb #80772.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Members of the INK4 family of cyclin dependent kinase inhibitors include p16INK4A, p15INK4B, p18INK4C and p19INK4D. The INK4 family members inhibit cyclin dependent kinases 4 and 6 (CDK4 and CDK6), causing cell cycle arrest in G1 phase. The INK4A-ARF-INK4B locus on chromosome 9p21, frequently lost in human cancer, encodes the INK4 family members p16INK5A and p15INK4B, as well as the unrelated protein, ARF (1).p16 INK4A expression, typically repressed in the absence of stress, is thought to drive cells into senescence, and p16 INK4A expression is a commonly used marker of senescent cells (2). p16INK4A protein expression is often altered in human cancer (3,4), and high expression is currently used as a predictive biomarker in cervical cancer (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: SLIT2 is an extracellular matrix-associated SLIT family member that functions as a ligand for roundabout (ROBO) family receptors (1). Activation of ROBO receptors by SLIT2 regulates various biological processes, including promoting cellular senescence via WNT inhibition (2), suppressing migration by enhanced β-catenin/E-cadherin association, regulating actin polymerization (4, 5), and suppressing cell proliferation induced by SDF1 and MCP1 (6, 7). In development, the SLIT-ROBO pathways play important roles in neuronal axon guidance, angiogenesis, and both kidney and mammary gland organogenesis. SLIT2 expression has been reported to suppress cancer cell growth, invasion, and metastasis, suggesting that modulation of SLIT2-ROBO signaling may have therapeutic potential in cancer biology (8, 9).

$299
100 µg
This Cell Signaling Technology antibody is conjugated to APC-Cy7® and tested in-house for direct flow cytometry analysis in mouse cells.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Flow Cytometry

Background: Major histocompatibility complex class II (MHC class II) molecules are heterodimeric, transmembrane glycoproteins expressed on the surface of antigen-presenting cells such as macrophages, dendritic cells, and B cells. Expression can also be induced on other cell types through interferon-γ signaling (1). Prior to being displayed on the cell membrane, MHC class II molecules are loaded with exogenous peptide antigens approximately 15-24 amino acids in length that were derived from endocytosed extracellular proteins digested in the lysosome (2). Antigen-presentation through MHC class II is required for T cell activation during the immune response to extracellular pathogens (2). In humans, the MHC class II protein complex is encoded by the human leukocyte antigen gene complex (HLA). HLAs corresponding to MHC class II are HLA-DP, HLA-DM, HLA-DOA, HLA-DOB, HLA-DQ, and HLA-DR (3).

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

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

Background: α-Actinin belongs to the spectrin family of cytoskeletal proteins. It was first recognized as an actin cross-linking protein, forming an antiparallel homodimer with an actin binding head at the amino terminus of each monomer. The α-actinin protein interacts with a large number of proteins involved in signaling to the cytoskeleton, including those involved in cellular adhesion, migration, and immune cell targeting (1). The interaction of α-actinin with intercellular adhesion molecule-5 (ICAM-5) helps to promote neurite outgrowth (2). In osteoblasts, interaction of α-actinin with integrins stabilizes focal adhesions and may protect cells from apoptosis (3). The cytoskeletal α-actinin isoforms 1 and 4 (ACTN1, ACTN4) are non-muscle proteins that are present in stress fibers, sites of adhesion and intercellular contacts, filopodia, and lamellipodia. The muscle isoforms 2 and 3 (ACTN2, ACTN3) localize to the Z-discs of striated muscle and to dense bodies and plaques in smooth muscle (1).

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

Application Methods: Western Blotting

Background: Glutamate oxaloacetate transaminase 1 (GOT1) catalyzes the interconversion of aspartate and oxaloacetate (1). The increased transamination primarily catalyzed by GOT1 leads to elevated levels of 2-hydroxyglutarate, which promotes methylation of the Foxp3 gene locus, inhibits Foxp3 expression and activates T helper 17 (TH17) cell differentiation (2). In addition, GOT1 is critical to the survival of cells with electron transport chain inhibition by generating aspartate, a metabolite determining the proliferation of these cells (3-4). Studies also show that GOT1 plays a key role in the noncanonical glutamine pathway that supports liver tumorigenesis (5).

$269
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: IHC-Leica® Bond™, Immunofluorescence (Frozen), Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation

Background: The protein phosphatase (PTP) receptor CD45 is a type I transmembrane protein comprised of a pair of intracellular tyrosine phosphatase domains and a variable extracellular domain generated by alternative splicing (1). The catalytic activity of CD45 is a function of the first phosphatase domain (D1) while the second phosphatase domain (D2) may interact with and stabilize the first domain, or recruit/bind substrates (2,3). CD45 interacts directly with antigen receptor complex proteins or activates Src family kinases involved in the regulation of T- and B-cell antigen receptor signaling (1). Specifically, CD45 dephosphorylates Src-family kinases Lck and Fyn at their conserved negative regulatory carboxy-terminal tyrosine residues and upregulates kinase activity. Conversely, studies indicate that CD45 can also inhibit Lck and Fyn by dephosphorylating their positive regulatory autophosphorylation site. CD45 appears to be both a positive and a negative regulator that conducts signals depending on specific stimuli and cell type (1). Human leukocytes including lymphocytes, eosinophils, monocytes, basophils, and neutrophils express CD45, while erythrocytes and platelets are negative for CD45 expression (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: TNFRSF9 is a member of the tumor necrosis factor receptor superfamily (1, 2). It is also called 4-1BB or CD137 (1, 2). 4-1BB/CD137/TNFRSF9 is expressed in activated CD4+ and CD8+ T cells, natural killer cells and dendritic cells (2-5). The ligand 4-1BBL/CD137L/TNFSF9 on antigen presenting cells binds to 4-1BB/CD137/TNFRSF9 and costimulates the activation of T cells (5). The binding of agonistic antibodies to 4-1BB/CD137/TNFRSF9 also leads to costimulation for T cell activation (5). Studies have shown the effectiveness of targeting 4-1BB/CD137/TNFRSF9 by its agonistic antibodies in cancer immunotherapy (6).

The One-Carbon Metabolism Antibody Sampler Kit provides an economical means of detecting select components involved in one-carbon metabolism pathway. The kit contains enough primary antibodies to perform at least two western blot experiments per antibody.

Background: One-carbon metabolism includes various enzymatic reactions involving the transfer of one-carbon groups mediated by folate cofactor (1). The activated one-carbon groups are used by various metabolic pathways, including purine synthesis, thymidine synthesis, and remethylation of homocysteine to methionine (1). S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1) is a member of the S-adenosylhomocysteine hydrolase family, which participates in the metabolism of S-adenosyl-L-homocysteine (2). Cystathionine beta-synthase (CBS) is a key enzyme involved in sulfur amino acid metabolism as it catalyzes the formation of cystathionine from serine and homocysteine (3,4). Cystathionine γ-lyase (CGL) is an enzyme in the transsulfuration pathway, a route in the metabolism of sulfur-containing amino acids (5). Methylenetetrahydrofolate reductase (MTHFR), a key enzyme in one-carbon metabolism, catalyzes the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate (1). 5-methyltetrahydrofolate donates its methyl group for remethylation of homocysteine to methionine (1). Methionine is further converted to S-adenosylmethionine (SAM), a major reactive methyl carrier (1). NADP+ dependent methylenetetrahydrofolate dehydrogenase 1-like (MTHFD1L) is a mitochondrial enzyme that catalyzes the production of formate from 10-formyl-tetrahydrofolate in one-carbon flow from mitochondria to cytoplasm (6,7). MTHFD2 is a bifunctional methylenetetrahydrofolate dehydrogenase/cyclohydrolase involved in mitochondrial folate metabolism (8). Serine hydroxymethyltransferase 1 (SHMT1) is a cytoplasmic serine hydroxylmethyltransferase (9,10). It catalyzes the conversion of serine to glycine with the transfer of β-carbon from serine to tetrahydrofolate (THF) to form 5, 10-methylene-THF (9, 10). The methylation of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP) is an essential step in the formation of thymine nucleotides, a process catalyzed by thymidylate synthase (TS or TYMS) (11-13).

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometric analysis in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-Smad2 (Ser465/467) (E8F3R) Rabbit mAb #18338.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry

Background: Members of the Smad family of signal transduction molecules are components of a critical intracellular pathway that transmit TGF-β signals from the cell surface into the nucleus. Three distinct classes of Smads have been defined: the receptor-regulated Smads (R-Smads), which include Smad1, 2, 3, 5, and 8; the common-mediator Smad (co-Smad), Smad4; and the antagonistic or inhibitory Smads (I-Smads), Smad6 and 7 (1-5). Activated type I receptors associate with specific R-Smads and phosphorylate them on a conserved carboxy terminal SSXS motif. The phosphorylated R-Smad dissociates from the receptor and forms a heteromeric complex with the co-Smad (Smad4), allowing translocation of the complex to the nucleus. Once in the nucleus, Smads can target a variety of DNA binding proteins to regulate transcriptional responses (6-8).

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: DARPP-32 (dopamine and cyclic AMP-regulated phosphoprotein, relative molecular mass 32,000) is a cytosolic protein highly enriched in medium-sized spiny neurons of the neostriatum (1). It is a bifunctional signaling molecule that controls serine/threonine kinase and serine/threonine phosphatase activity (2). Dopamine stimulates phosphorylation of DARPP-32 through D1 receptors and activation of PKA. PKA phosphorylation of DARPP-32 at Thr34 converts it into an inhibitor of protein phosphatase 1 (1). DARPP-32 is converted into an inhibitor of PKA when phosphorylated at Thr75 by cyclin-dependent kinase 5 (CDK5) (2). Mice containing a targeted deletion of the DARPP-32 gene exhibit an altered biochemical, electrophysiological, and behavioral phenotype (3).

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: 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).

$260
100 µg
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: The p53 tumor suppressor protein plays a major role in cellular response to DNA damage and other genomic aberrations. Activation of p53 can lead to either cell cycle arrest and DNA repair or apoptosis (1). p53 is phosphorylated at multiple sites in vivo and by several different protein kinases in vitro (2,3). DNA damage induces phosphorylation of p53 at Ser15 and Ser20 and leads to a reduced interaction between p53 and its negative regulator, the oncoprotein MDM2 (4). MDM2 inhibits p53 accumulation by targeting it for ubiquitination and proteasomal degradation (5,6). p53 can be phosphorylated by ATM, ATR, and DNA-PK at Ser15 and Ser37. Phosphorylation impairs the ability of MDM2 to bind p53, promoting both the accumulation and activation of p53 in response to DNA damage (4,7). Chk2 and Chk1 can phosphorylate p53 at Ser20, enhancing its tetramerization, stability, and activity (8,9). p53 is phosphorylated at Ser392 in vivo (10,11) and by CAK in vitro (11). Phosphorylation of p53 at Ser392 is increased in human tumors (12) and has been reported to influence the growth suppressor function, DNA binding, and transcriptional activation of p53 (10,13,14). p53 is phosphorylated at Ser6 and Ser9 by CK1δ and CK1ε both in vitro and in vivo (13,15). Phosphorylation of p53 at Ser46 regulates the ability of p53 to induce apoptosis (16). Acetylation of p53 is mediated by p300 and CBP acetyltransferases. Inhibition of deacetylation suppressing MDM2 from recruiting HDAC1 complex by p19 (ARF) stabilizes p53. Acetylation appears to play a positive role in the accumulation of p53 protein in stress response (17). Following DNA damage, human p53 becomes acetylated at Lys382 (Lys379 in mouse) in vivo to enhance p53-DNA binding (18). Deacetylation of p53 occurs through interaction with the SIRT1 protein, a deacetylase that may be involved in cellular aging and the DNA damage response (19).

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: 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).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Members of the INK4 family of cyclin dependent kinase inhibitors include p16INK4A, p15INK4B, p18INK4C and p19INK4D. The INK4 family members inhibit cyclin dependent kinases 4 and 6 (CDK4 and CDK6), causing cell cycle arrest in G1 phase. The INK4A-ARF-INK4B locus on chromosome 9p21, frequently lost in human cancer, encodes the INK4 family members p16INK5A and p15INK4B, as well as the unrelated protein, ARF (1).p16 INK4A expression, typically repressed in the absence of stress, is thought to drive cells into senescence, and p16 INK4A expression is a commonly used marker of senescent cells (2). p16INK4A protein expression is often altered in human cancer (3,4), and high expression is currently used as a predictive biomarker in cervical cancer (5).

$269
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: IHC-Leica® Bond™, Immunohistochemistry (Paraffin)

Background: Forkhead box (Fox) proteins are a family of evolutionarily conserved transcription factors containing a sequence known as Forkhead box or winged helix DNA binding domain (1). The human genome contains 43 Fox proteins that are divided into subfamilies. The FoxP subfamily has four members, FoxP1 - FoxP4, which are broadly expressed and play important roles in organ development, immune response and cancer pathogenesis (2-4). The FoxP subfamily has several characteristics that are atypical among Fox proteins: their Forkhead domain is located at the carboxy-terminal region and they contain motifs that promote homo- and heterodimerization. FoxP proteins usually function as transcriptional repressors (4,5).FoxP3 is crucial for the development of T cells with regulatory properties (Treg) (6). Mutations in FoxP3 are associated with immune dysregulation, polyendocrinopathy, enteropathy, and X-linked syndrome (IPEX) (7), while overexpression in mice causes severe immunodeficiency (8). Research studies have shown that FoxP3 functions as a tumor suppressor in several types of cancer (9-11).