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Product listing: Perforin (E3W4I) Rabbit mAb, UniProt ID P10820 #31647 to SignalSilence® VASP siRNA II, UniProt ID P50552 #7658

$269
100 µl
APPLICATIONS
REACTIVITY
Mouse

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

Background: Granzymes are a family of serine proteases expressed by cytotoxic T lymphocytes and natural killer (NK) cells and are key components of immune responses to pathogens and transformed cells (1). Granzymes are synthesized as zymogens and are processed into mature enzymes by cleavage of a leader sequence. They are released by exocytosis in lysosome-like granules containing perforin, a membrane pore-forming protein. Granzyme B has the strongest apoptotic activity of all the granzymes as a result of its caspase-like ability to cleave substrates at aspartic acid residues thereby activating procaspases directly and cleaving downstream caspase substrates (2,3).

$269
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, IHC-Leica® Bond™, Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

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).

$269
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

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

Background: IDH2 is one of three isocitrate dehydrogenases (IDH1-3) that catalyze the oxidative decarboxylation of isocitrate to produce CO2 and α-ketoglutarate (α-KG). These enzymes belong to two distinct subclasses that utilize either NAD or NADP+ as an electron acceptor. IDH2 is an NADP+-dependent isocitrate dehydrogenase expressed primarily in the mitochondria, where it also functions in the TCA cycle (1,2). Mutations in IDH2 or its cytoplasmic counterpart (IDH1) have been reported in glioblastoma multiforme (3), acute myeloid leukemia (4,5), and other malignancies (6). Research studies have shown that gain-of-function mutations in IDH2 can lead to the accumulation and secretion of the oncometabolite R-2-hydroxyglutarate (2HG) in cancer cells (6,7).

$269
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: IDH1 is one of three isocitrate dehydrogenases that catalyze the oxidative decarboxylation of isocitrate to α-ketoglutarate (α-KG). These enzymes exist in two distinct subclasses that utilize either NAD or NADP+ respectively, as an electron acceptor (1). IDH1 is the NADP+-dependent isocitrate dehydrogenase found in the cytoplasm and peroxisomes. IDH2 and 3 are mitochondrial enzymes that also function in the Krebs cycle. IDH1 is inactivated by phosphorylation at Ser113 and contains a clasp-like domain wherein both polypeptide chains in the dimer interlock (2,3). IDH1 is expressed in a wide range of species and also in organisms that lack a complete citric acid cycle. Mutations in IDH1 have been reported in glioblastoma (4), acute myeloid leukemia (5,6), and other malignancies (7). IDH1 appears to function as a tumor suppressor that, when mutationally inactivated, contributes to tumorigenesis in part through induction of the HIF-1 pathway (8).

$269
100 µl
APPLICATIONS
REACTIVITY
Mouse

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

Background: Granzymes are a family of serine proteases expressed by cytotoxic T lymphocytes and natural killer (NK) cells and are key components of immune responses to pathogens and transformed cells (1). Granzymes are synthesized as zymogens and are processed into mature enzymes by cleavage of a leader sequence. They are released by exocytosis in lysosome-like granules containing perforin, a membrane pore-forming protein. Granzyme B has the strongest apoptotic activity of all the granzymes as a result of its caspase-like ability to cleave substrates at aspartic acid residues thereby activating procaspases directly and cleaving downstream caspase substrates (2,3).

$269
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: The protein product of the DEK oncogene is a nuclear phosphoprotein that is highly conserved among higher eukaryotic organisms and preferentially expressed in actively proliferating and/or malignant cells (1,2). DEK is an abundant, non-histone chromosomal protein that establishes and maintains heterochromatin by interacting with HP1a, enhancing HP1a binding to tri-methyl histone H3 Lys9 and stabilizing local tri-methyl histone H3 Lys9 levels (3). DEK localized to euchromatin represses transcription by interacting with transcription factors such as RelA/p65 (4). The DEK protein also associates with mRNA processing factors to regulate splicing and nuclear export (5,6).The DEK proto-oncogene functions as a negative regulator of cellular differentiation, senescence, and apoptosis. DEK is translocated and/or over-expressed in a number of different cancers, including acute myeloid leukemia, breast cancer, cervical cancer, hepatocellular carcinoma, melanoma, and small cell lung cancer (1,2). In addition to the role of DEK in cancer biology, which is mainly related to its intracellular functions, extracellular DEK is implicated in the pathogenesis of autoimmune disorders (1,2). Circulating autoantibodies to DEK have been identified in the serum of patients with autoimmune diseases, including juvenile idiopathic arthritis, sarcoidosis, and systemic lupus erythematosus. DEK is secreted by human monocyte-derived macrophages and apoptotic T-lymphocytes and can act as a chemotactic, pro-inflammatory factor (7,8). Exogenous DEK can penetrate neighboring cells, and translocate to the nucleus to carry out its endogenous nuclear functions (9). IL-8 induced secretion of DEK from macrophages serves as a chemoattractant for peripheral blood leukocytes (7).

$269
100 µl
APPLICATIONS
REACTIVITY
Mouse

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

Background: CD40, also known as tumor necrosis factor receptor superfamily member 5 (TNFRSF5), is a type I transmembrane protein expressed on the surface of B cells and professional antigen-presenting cells of the immune system, as well as on several non-hematopoietic cell types and cancers (1-4). CD40 interacts with CD40 ligand (CD40L/TNFSF5), which is expressed primarily on activated T cells but has also been reported on blood platelets, mast cells, basophils, NK cells, and B cells (5). Upon engagement with CD40L, CD40 signals through TNF receptor associated factors and MAP kinase signaling pathways, resulting in a wide variety of immune and inflammatory responses, including dendritic cell activation and cross-presentation, T cell-dependent immunoglobulin class switching, memory B cell development, and germinal center formation (6-8). The CD40/CD40L axis is essential for the initiation and progression of cellular and humoral adaptive immunity, and is an important area of interest in the study of tumor immunology, neurodegenerative diseases, vascular diseases, and inflammatory disorders (9-12).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: Myeloperoxidase (MPO) is a peroxidase enzyme that is part of the host defense system of polymorphonuclear leukocytes (reviewed in 1). The gene for MPO was cloned independently from several laboratories (2-5). A decrease in MPO expression was noticed upon differentiation of HL-60 cells (5). MPO catalyzes the reaction of hydrogen peroxide and chloride (or other halides) to produce hypochlorous acid and other potent antimicrobial oxidants. Knockout mice of MPO are impaired in clearing select microbial infections (6). Processing of mature MPO from an initial 80-90 kDa translation product involves insertion of a heme moiety, glycosylation, and proteolytic cleavage. The mature protein is a tetramer of two heavy chains (60 kDa) and two light chains (12 kDa). It is abundantly expressed in neutrophils and monocytes and secreted during their activation. Heightened MPO levels have been associated with tissue damage and a number of pathological conditions (1).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Serum albumin is the most abundant protein in plasma. It accounts for over 50% of total human plasma protein content, having a concentration of approximately 40 g/L. Albumin is predominantly synthesized in the liver and is a major transportation component for many endogenous and exogenous compounds, including fatty acids, steroid hormones, metabolites and drugs. It is also responsible for maintaining colloid osmotic pressure and may affect microvascular integrity (1).

$262
3 nmol
300 µl
SignalSilence® mTOR siRNA I (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit mTOR expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Mouse

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

$262
3 nmol
300 µl
SignalSilence® MDR1/ABCB1 siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit MDR1/ABCB1 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: MDR1/ABCB1 belongs to the Mdr/Tap subfamily of the ATP-binding cassette transporter superfamily (1). Multidrug resistance 1 (MDR1) serves as an efflux pump for xenobiotic compounds with broad substrate specificity. MDR1 substrates include therapeutic agents such as actinomycin D, etoposide, imatinib, and doxorubicin, as well as endogenous molecules including β-amyloids, steroid hormones, lipids, phospholipids, cholesterol, and cytokines (2). Research studies have shown that MDR1 reduces drug accumulation in cancer cells, allowing the development of drug resistance (3-5). On the other hand, MDR1 expressed in the plasma membrane of cells in the blood-brain, blood-cerebral spinal fluid, or blood-placenta barriers restricts the permeability of drugs into these organs from the apical or serosal side (6,7). MDR1 is also expressed in normal tissues with excretory function such as small intestine, liver, and kidney (7). Intracellular MDR1 has been detected in the ER, vesicles, and nuclear envelope, and has been associated with cell trafficking machinery (8). Other reported functions of MDR1 include viral resistance, cytokine trafficking (9,10), and lipid homeostasis in the peripheral and central nervous system (11-13).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Gasdermin D (GSDMD), a member of the gasdermin family that includes GSDMA, GSDMB, and GSMDC, has been reported to have a critical role as a downstream effector of pyroptosis (1,2). Pyroptosis is a lytic type of cell death triggered by inflammasomes, multiprotein complexes assembled in response to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs) that result in the activation of caspase-1 and subsequent cleavage of pro-inflammatory cytokines IL-1β and IL-18 (3). Gasdermin D was identified by two independent groups as a substrate of inflammatory caspases, caspase-1 and caspase-11/4/5, producing two fragments: GSDMD-N and GSDMD-C. Cleavage results in release of an intramolecular inhibitory interaction between the N- and C-terminal domains, allowing the N-terminal fragment GSMDM-N to initiate pyroptosis through the formation of pores on the plasma membrane (4-7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunofluorescence (Frozen), Western Blotting

Background: Amyloid β (Aβ) precursor protein (APP) is a 100-140 kDa transmembrane glycoprotein that exists as several isoforms (1). The amino acid sequence of APP contains the amyloid domain, which can be released by a two-step proteolytic cleavage (1). The extracellular deposition and accumulation of the released Aβ fragments form the main components of amyloid plaques in Alzheimer's disease (1). APP can be phosphorylated at several sites, which may affect the proteolytic processing and secretion of this protein (2-5). Phosphorylation at Thr668 (a position corresponding to the APP695 isoform) by cyclin-dependent kinase is cell-cycle dependent and peaks during G2/M phase (4). APP phosphorylated at Thr668 exists in adult rat brain and correlates with cultured neuronal differentiation (5,6).

$260
100 µl

Background: N6-methyladenosine (m6A) is a post-transcriptional modification found in various RNA subtypes. While the presence of m6A in RNA was described decades ago, the lack of tools has made interrogating the epitranscriptomic landscape challenging (1,2). With the emergence of new technologies such as miCLIP and NG-RNA-seq, researchers have been able to show that m6A is a biologically relevant mark in mRNA that is enriched in 3’ UTRs and stop codons (3,4). The m6A writer complex consists of a core heterodimer of methyltransferase-like protein 3 (METTL3) and methytransferase-like protein 14 (METTL14), and the additional regulatory proteins Virlizer/VIRMA and Wilms tumor 1-associated protein (WTAP) (5). METTL3 is the catalytic methyltransferase subunit and METTL14 is the target recognition subunit that binds to RNA (6). The Virilzer/VIRMA protein directs m6A methylation to the 3’ UTRs and stop codons, and WTAP targets the complex to nuclear speckles, which are sites of RNA processing (7). Less is known about readers and erasers of m6A, and while the fat mass and obesity-associated protein FTO was the first discovered m6A demethylase, subsequent studies demonstrated that this enzyme may prefer the closely related m6Am mark in vivo (8,9). ALKBH5 was later shown to be a bona fide m6A demethylase enzyme, contributing to the idea that the m6A modification is dynamically regulated (10). Readers of the m6A mark include the YTH protein family, which can bind to m6A and influence mRNA stability and translation efficiency (3,11-13). The m6A mark and machinery have been shown to regulate a variety of cellular functions, including RNA splicing, translational control, pluripotency and cell fate determination, neuronal function, and disease (1, 14-17). The m6A writer complex has been linked to various cancer types including AML and endometrial cancers (18,19). Additionally, m6A has been implicated in resistance to chemotherapy (20).

$262
3 nmol
300 µl
SignalSilence® NDP52 siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit NDP52 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: NDP52 (CALCOCO2) is ubiquitously expressed and composed of an amino-terminal SKICH domain, followed by a coiled-coil domain, and two zinc finger domains (1). It has recently been reported to act as an autophagy receptor that binds cytosolic ubiquitinated bacteria, leading to autophagy activation and pathogen clearance (1-3). NDP52 binds ubiquitin through its zinc finger domain and simultaneously binds LC3, which directs the bacteria into autophagosomes. In addition, NDP52 interacts with Nap1 and SINTBAD to recruit TBK1 to ubiquitinated bacteria (1).

$262
3 nmol
300 µl
SignalSilence® MKK7 siRNA II from Cell Signaling Technology (CST) allows the researcher to specifically inhibit MKK7 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: MKK7 is a MAP kinase kinase that serves as a specific activator of the SAPK/JNK pathway (1,2). MKK7 is strongly activated by TNF-α, as well as other environmental stresses, whereas SEK1/MKK4, which activates both p38 and SAPK/JNK pathways, is not activated by TNF-α (2). Sequence alignment of the activation loop of the MAP kinase kinase family members indicates that Ser271 and Thr275 are potential phosphorylation sites that are crucial for the kinase acivity.

$262
3 nmol
300 µl
SignalSilence® IGF-I Receptor siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit IGF-I Receptor expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. IGF-I Receptor siRNA I is 100% homologous with IGF-I Receptor α and β mRNA. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: Type I insulin-like growth factor receptor (IGF-IR) is a transmembrane receptor tyrosine kinase that is widely expressed in many cell lines and cell types within fetal and postnatal tissues (1-3). Receptor autophosphorylation follows binding of the IGF-I and IGF-II ligands. Three tyrosine residues within the kinase domain (Tyr1131, Tyr1135, and Tyr1136) are the earliest major autophosphorylation sites (4). Phosphorylation of these three tyrosine residues is necessary for kinase activation (5,6). Insulin receptors (IRs) share significant structural and functional similarity with IGF-I receptors, including the presence of an equivalent tyrosine cluster (Tyr1146/1150/1151) within the kinase domain activation loop. Tyrosine autophosphorylation of IRs is one of the earliest cellular responses to insulin stimulation (7). Autophosphorylation begins with phosphorylation at Tyr1146 and either Tyr1150 or Tyr1151, while full kinase activation requires triple tyrosine phosphorylation (8).

$262
3 nmol
300 µl
SignalSilence® Cyclin D1 siRNA I (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit Cyclin D1 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Mouse

Background: Activity of the cyclin-dependent kinases CDK4 and CDK6 is regulated by T-loop phosphorylation, by the abundance of their cyclin partners (the D-type cyclins), and by association with CDK inhibitors of the Cip/Kip or INK family of proteins (1). The inactive ternary complex of cyclin D/CDK4 and p27 Kip1 requires extracellular mitogenic stimuli for the release and degradation of p27 concomitant with a rise in cyclin D levels to affect progression through the restriction point and Rb-dependent entry into S-phase (2). The active complex of cyclin D/CDK4 targets the retinoblastoma protein for phosphorylation, allowing the release of E2F transcription factors that activate G1/S-phase gene expression (3). Levels of cyclin D protein drop upon withdrawal of growth factors through downregulation of protein expression and phosphorylation-dependent degradation (4).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: IFN-γ plays key roles in both the innate and adaptive immune response. IFN-γ activates the cytotoxic activity of innate immune cells, such as macrophages and NK cells (1,2). IFN-γ production by NK cells and antigen presenting cells (APCs) promotes cell-mediated adaptive immunity by inducing IFN-γ production by T lymphocytes, increasing class I and class II MHC expression, and enhancing peptide antigen presentation (1). The anti-viral activity of IFN-γ is due to its induction of PKR and other regulatory proteins. Binding of IFN-γ to the IFNGR1/IFNGR2 complex promotes dimerization of the receptor complexes to form the (IFNGR1/IFNGR2)2 -IFN-γ dimer. Binding induces a conformational change in receptor intracellular domains and signaling involves Jak1, Jak2, and Stat1 (3). The critical role of IFN-γ in amplification of immune surveillance and function is supported by increased susceptibility to pathogen infection by IFN-γ or IFNGR knockout mice and in humans with inactivating mutations in IFNGR1 or IFNGR2. IFN-γ also appears to have a role in atherosclerosis (4).

$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

Application Methods: Western Blotting

Background: Macrophage Scavenger receptor types I and II (MSR1, and also known as SCARA1) are members of the class A macrophage scavenger receptor family. These proteins bind large quantities of modified lipoproteins and promote endocytosis. Upregulation of MSR1 in infiltrating myeloid cells may mediate clearance of specific damage signals in response to tissue injury, including ischemic stroke (1). MSR1 germ line mutations are also associated with increased prostate cancer susceptibility in some patient cohorts (2). MSR1 is observed to be upregulated in differentiated THP-1 cells (3).

$263
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to violetFluor™ 450 and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Cluster of Differentiation 8 (CD8) is a disulphide-linked heterodimer consisting of the unrelated α and β subunits. Each subunit is a glycoprotein composed of a single extracellular Ig-like domain, a polypeptide linker, a transmembrane part and a short cytoplasmic tail. On T cells, CD8 is the coreceptor for the T cell receptor (TCR), and these two distinct structures recognize the Antigen–Major Histocompatibility Complex (MHC). Specifically, the Ig-like domain of CD8α interacts with the α3-domain of the MHC class I molecule. CD8 ensures specificity of the TCR–antigen interaction, prolongs the contact between the T cell and the antigen presenting cell, and the α chain recruits the tyrosine kinase Lck, which is essential for T cell activation (1).

$263
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to PerCP-Cy5.5® and tested in-house for direct flow cytometry analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Cluster of Differentiation 4 (CD4) is a glycoprotein composed of an amino-terminal extracellular domain (four domains: D1-D4 with Ig-like structures), a transmembrane part and a short cytoplasmic tail. CD4 is expressed on the surface of T helper cells, regulatory T cells, monocytes, macrophages and dendritic cells, and plays an important role in the development and activation of T cells. On T cells, CD4 is the co-receptor for the T cell receptor (TCR), and these two distinct structures recognize the Antigen–Major Histocompatibility Complex (MHC). Specifically, the D1 domain of CD4 interacts with the β2-domain of the MHC class II molecule. CD4 ensures specificity of the TCR–antigen interaction, prolongs the contact between the T cell and the antigen presenting cell and recruits the tyrosine kinase Lck, which is essential for T cell activation (1).

$263
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to violetFluor™ 450 and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: When T cells encounter antigens via the T cell receptor (TCR), information about the quantity and quality of antigens is relayed to the intracellular signal transduction machinery (1). This activation process depends mainly on CD3 (Cluster of Differentiation 3), a multiunit protein complex that directly associates with the TCR. CD3 is composed of four polypeptides: ζ, γ, ε and δ. Each of these polypeptides contains at least one immunoreceptor tyrosine-based activation motif (ITAM) (2). Engagement of TCR complex with foreign antigens induces tyrosine phosphorylation in the ITAM motifs and phosphorylated ITAMs function as docking sites for signaling molecules such as ZAP-70 and p85 subunit of PI-3 kinase (3,4). TCR ligation also induces a conformational change in CD3ε, such that a proline region is exposed and then associates with the adaptor protein Nck (5).

$262
3 nmol
300 µl
SignalSilence® γ-Catenin siRNA II (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit γ-catenin expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis
REACTIVITY
Mouse

Background: Also known as plakoglobin, γ-catenin is a member of the Armadillo family of signaling molecules, which includes β-catenin and the Drosophila protein armadillo (1). This family of proteins is involved in Wnt signaling, which is important in embryonic development and in tumorigenesis (2-3). Although the two vertebrate proteins β- and γ-catenin display sequence homology, γ-catenin likely plays a role distinct from that of β-catenin (1, 4-6). γ-catenin localizes to desmosomes and adherens junctions, both sites of intercellular adhesion, and interacts with the cytoplasmic domains of classical and desmosomal cadherins. Interaction of γ- or β-catenin with α-catenin, desmoplakin and other junction proteins provides a link between intercellular junctions and the actin and intermediate filament cytoskeleton. Maintenance and/or modification of this link is vital for control of cell adhesion and migration (1). γ-catenin is modified by phosphorylation, affecting both adhesion and β-catenin dependent transcription (7), and by and O-glycosylation, affecting adhesion (8). Recent evidence suggests that γ-catenin regulates desmosomal adhesion in response to growth factor stimulation (9).

$262
3 nmol
300 µl
SignalSilence® γ-Catenin siRNA I (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit γ-catenin expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Mouse

Background: Also known as plakoglobin, γ-catenin is a member of the Armadillo family of signaling molecules, which includes β-catenin and the Drosophila protein armadillo (1). This family of proteins is involved in Wnt signaling, which is important in embryonic development and in tumorigenesis (2-3). Although the two vertebrate proteins β- and γ-catenin display sequence homology, γ-catenin likely plays a role distinct from that of β-catenin (1, 4-6). γ-catenin localizes to desmosomes and adherens junctions, both sites of intercellular adhesion, and interacts with the cytoplasmic domains of classical and desmosomal cadherins. Interaction of γ- or β-catenin with α-catenin, desmoplakin and other junction proteins provides a link between intercellular junctions and the actin and intermediate filament cytoskeleton. Maintenance and/or modification of this link is vital for control of cell adhesion and migration (1). γ-catenin is modified by phosphorylation, affecting both adhesion and β-catenin dependent transcription (7), and by and O-glycosylation, affecting adhesion (8). Recent evidence suggests that γ-catenin regulates desmosomal adhesion in response to growth factor stimulation (9).

$262
3 nmol
300 µl
SignalSilence® β-Catenin siRNA II (Mouse Specific) from Cell Signaling Technology (CST) allows the researcher to specifically inhibit β-catenin expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Mouse

Background: β-Catenin is a key downstream effector in the Wnt signaling pathway (1). It is implicated in two major biological processes in vertebrates: early embryonic development (2) and tumorigenesis (3). CK1 phosphorylates β-catenin at Ser45. This phosphorylation event primes β-catenin for subsequent phosphorylation by GSK-3β (4-6). GSK-3β destabilizes β-catenin by phosphorylating it at Ser33, Ser37, and Thr41 (7). Mutations at these sites result in the stabilization of β-catenin protein levels and have been found in many tumor cell lines (8).

$262
3 nmol
300 µl
SignalSilence® YB1 siRNA from Cell Signaling Technology (CST) allows the researcher to specifically inhibit YB1 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products are rigorously tested in-house and have been shown to reduce target protein expression in specified cell lines.
REACTIVITY
Human

Background: The Y-box binding protein 1 (YB1) belongs to a family of evolutionarily conserved, multifunctional Y-box proteins that bind single-stranded DNA and RNA and function as regulators of transcription, RNA metabolism, and protein synthesis (1). YB1 binds to Y-box sequences (TAACC) found in multiple gene promoters and can positively or negatively regulate transcription. YB1 activates genes associated with proliferation and cancer, such as cyclin A, cyclin B1, matrix metalloproteinase-2 (MMP-2), and the multi-drug resistance 1 (MDR1) gene (2-4). YB1 represses genes associated with cell death, including the Fas cell death-associated receptor and the p53 tumor suppressor gene (5-7). It also interacts with the RNA-splicing factor SRp30c and stabilizes interleukin-2 (IL-2) mRNA upon induction of T lymphocytes by IL-2 (8,9). The majority of YB1 protein localizes to the cytoplasm, with a minor pool found in the nucleus; however, nuclear localization appears to be critical for its role in promoting proliferation. Nuclear translocation is cell cycle regulated, with YB1 protein accumulating in the nucleus during G1/S phase (2). In addition, nuclear translocation is induced in response to extracellular stimuli such as hyperthermia and UV irradiation, or treatment of cells with thrombin, interferons, or insulin-like growth factor (IGF-I) (2,10). Treatment of the MCF7 breast cancer cell line with IGF-I results in Akt-mediated phosphorylation of YB1 at Ser102, which is required for nuclear translocation of YB1 and its ability to promote anchorage-independent growth (10). Research studies have shown that YB1 is overexpressed in many malignant tissues, including breast cancer, non-small cell lung carcinoma, ovarian adenocarcinomas, human osteosarcomas, colorectal carcinomas, and malignant melanomas. Investigators have shown that nuclear YB1 expression correlates with high levels of proliferation, drug resistance, and poor tumor prognosis (2,7,10).

$262
3 nmol
300 µl
SignalSilence® VPRBP siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit VPRBP expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: The HIV-1 viral protein R (Vpr)-binding protein (VPRBP, DCAF1) is a substrate-specific adaptor for the CUL4-based ubiquitin ligase complex that consists of CUL4A, RBX1, and DDB1 (1). VPRBP protein structure contains a central LIS1 homology (LisH) motif responsible for dimerization, and two carboxy-terminal WD-40 motifs involved in Vpr and DDB1 binding (2-4). Research studies demonstrate that VPRBP plays a role in hepatic lipid metabolism by promoting the ubiquitin-dependent proteasomal degradation of the TR4 nuclear receptor, which is involved in lipid homeostasis (5). The VPRBP protein plays a role in mammalian germ cell development through regulation of TET methylcytosine dioxygenase activation (6). Additional studies show that VPRBP exhibits kinase activity and phosphorylates histone H2A at Ser120, which blocks tumor suppressor gene transcription (7). The tumor suppressor Merlin/NF2 inhibits tumorigenesis through interaction with and suppression of the CUL4A-RBX1-DDB1-VPRBP complex (8).

$262
3 nmol
300 µl
SignalSilence® VASP siRNA II from Cell Signaling Technology (CST) allows the researcher to specifically inhibit VASP expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: Vasodilator-stimulated phosphoprotein (VASP) was originally characterized as a substrate of both cGMP- and cAMP-dependent kinases (PKG and PKA, or cGPK and cAPK, respectively) (1). It is now believed that VASP belongs to the Ena/VASP family of adaptor proteins linking the cytoskeletal system to the signal transduction pathways and that it functions in cytoskeletal organization, fibroblast migration, platelet activation and axon guidance (2,3). Three phosphorylation sites, Ser157, Ser239, and Thr278, have been identified. Ser239 is the major PKG phosphorylation site while Ser157 is the major PKA phosphorylation site (4). Evidence suggests that VASP phosphorylation reduces its association with actin and has a negative effect on actin polymerization (5). Phosphorylation at Ser239 of VASP is a useful marker for monitoring PKG activation and signaling (6,7).