Microsize antibodies for $99 | Learn More >>

Product listing: RYBP Antibody, UniProt ID Q8N488 #33924 to Di-Methyl-Histone H3 (Lys4) (C64G9) Rabbit mAb (PE Conjugate), UniProt ID P68431 #31777

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Western Blotting

Background: Ring1 and YY1-binding protein (RYBP) is a widely expressed nuclear protein that functions as a modulator of Ring1A/Ring1B-dependent histone H2A monoubiquitylation (1-3). Ring1A and Ring1B proteins function as the catalytic core subunits of polyclomb repressor complex 1 (PRC1), which acts to repress gene expression in part through monoubiquitination of histone H2A on Lys119 (4). By binding to both the YY1 DNA-binding transcription factor and Ring1A/Ring1B, RYPB is able to recruit the PRC1 complex to target loci independent of prior tri-methylation of histone H3 Lys27 by the EZH2-dependent PRC2 complex (2,3). RYBP also binds monoubiquitinated H2A Lys119 and may act to stabilize or spread binding of PRC1 across large domains of repressed chromatin (5). In addition, RYBP directly stimulates the ubiquitination activity of Ring1A/Ring1B and is required for proper differentiation of stem cells along multiple cell lineages (2,3,6,7). RYBP has also been shown to bind MDM2 and block ubiquitination and degradation of p53, leading to cell cycle arrest and apoptosis in response to DNA damage (8). Many studies demonstrate that RYBP functions as a tumor suppressor protein. RYBP expression is decreased in multiple cancers, including non-small cell lung cancer, hepatocellular carcinoma, and glioblastoma with decreased expression correlating with metastasis and poor prognosis (8-11).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Chromatin IP, Western Blotting

Background: Activating transcription factor 3 (ATF-3) is a basic leucine zipper-type transcription factor belonging to the ATF/cAMP responsive element binding protein family. ATF-3 can form homodimers or heterodimers with other family members and depending on the cell types and promoter context, it can suppress or activate the transcription of its target genes (1,2). Expression of ATF-3 is induced by a variety of factors including cytokines, genotoxic agents, and physiological stress. For example, both metformin and high-density lipoprotein (HDL) can induce ATF-3 expression in macrophages (1,3-5). Research studies also indicate that ATF-3 can function as an oncogene or a tumor suppressor depending on the context (6,7).

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

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

Background: The methylation state of lysine residues in histone proteins is a major determinant of the formation of active and inactive regions of the genome and is crucial for proper programming of the genome during development (1,2). Jumonji C (JmjC) domain-containing proteins represent the largest class of potential histone demethylase proteins (3). The JmjC domain can catalyze the demethylation of mono-, di-, and tri-methyl lysine residues via an oxidative reaction that requires iron and α-ketoglutarate (3). Based on homology, both humans and mice contain at least 30 such proteins, which can be divided into 7 separate families (3). The three members of the UTX/UTY family include the ubiquitously transcribed X chromosome tetratricopeptide repeat protein (UTX), the ubiquitously transcribed Y chromosome tetratricopeptide repeat protein (UTY) and JmjC domain-containing protein 3 (JMJD3) (3). This family of proteins has been shown to demethylate both di- and tri-methyl histone H3 Lys 27 (4-8). The UTX gene escapes X inactivation in females and is ubiquitously expressed (9). UTX functions to regulate HOX gene expression during development (4-6). JMJD3 functions to regulate gene expression in macrophages responding to various inflammatory stimuli and has been shown to be upregulated in prostate cancer (7,8). Both UTX and JMJD3 interact with mixed-lineage leukemia (MLL) complexes 2 and 3, both of which have been shown to methylate histone H3 at Lys4 (6,7). The UTY gene is expressed in most tissues in the male mouse (10).

$305
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. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated Ikaros (D6N9Y) Rabbit mAb #14859.
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Flow Cytometry

Background: The Ikaros family of zinc-finger DNA-binding proteins belongs to the Kruppel transcription factor superfamily. Ikaros proteins are characterized by the presence of an amino-terminal zinc finger DNA-binding domain and a carboxy-terminal dimerization domain. Members of the Ikaros family include Ikaros, Aiolos, Helios, EOS, and Pegasus (1). All family members can form homodimers and heterodimers with other members of the Ikaros family. Most also contain multiple isoforms that are generated as a result of differential splicing, with some isoforms behaving in a dominant negative manner upon dimerization (2).Ikaros (IKZF1, LYF1) is the prototypical Ikaros family zinc-finger transcription factor and is expressed abundantly in lymphoid cells. Genetic studies in mice demonstrate that Ikaros is a tumor suppressor that is important for the normal development of B, T, natural killer, and dendritic cells (3,4). Additional studies show that imbalanced expression of different Ikaros isoforms, as well as mutations in the corresponding IKAROS gene, can be associated with a number of hematologic malignancies in humans (2,5,6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: Acetylation of the histone tail causes chromatin to adopt an "open" conformation, allowing increased accessibility of transcription factors to DNA. The identification of histone acetyltransferases (HATs) and their large multiprotein complexes has yielded important insights into how these enzymes regulate transcription (1,2). HAT complexes interact with sequence-specific activator proteins to target specific genes. In addition to histones, HATs can acetylate nonhistone proteins, suggesting multiple roles for these enzymes (3). In contrast, histone deacetylation promotes a "closed" chromatin conformation and typically leads to repression of gene activity (4). Mammalian histone deacetylases can be divided into three classes on the basis of their similarity to various yeast deacetylases (5). Class I proteins (HDACs 1, 2, 3, and 8) are related to the yeast Rpd3-like proteins, those in class II (HDACs 4, 5, 6, 7, 9, and 10) are related to yeast Hda1-like proteins, and class III proteins are related to the yeast protein Sir2. Inhibitors of HDAC activity are now being explored as potential therapeutic cancer agents (6,7).

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to allophycocyanin (APC) 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-p44/42 MAPK (Erk1/2) (Thr202/Tyr204) (197G2) Rabbit mAb #4377.
APPLICATIONS
REACTIVITY
D. melanogaster, Human, Mink, Monkey, Mouse, Pig, Rat, Zebrafish

Application Methods: Flow Cytometry

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

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

Application Methods: Chromatin IP, Immunoprecipitation, Western Blotting

Background: The modulation of chromatin structure is an essential component in the regulation of transcriptional activation and repression. Modifications can be made by at least two evolutionarily conserved strategies, through the disruption of histone-DNA contacts by ATP-dependent chromatin remodelers, or by histone tail modifications including methylation and acetylation. One of the four classes of ATP-dependent histone remodelers is the SWI/SNF complex, the central catalytic subunit of which is Brg1 or the highly related protein hBRM (1). This SWI/SNF complex contains varying subunits but its association with either Brg1 or hBRM remains constant (1). SWI/SNF complexes have been shown to regulate gene activation, cell growth, the cell cycle and differentiation (1). Brg1/hBRM have been shown to regulate transcription through enhancing transcriptional activation of glucocorticoid receptors (2). Although usually associated with transcriptional activation, Brg1/hBRM have also been found in complexes associated with transcriptional repression including with HDACs, Rb and Tif1β (3-5). Brg1/hBRM plays a vital role in the regulation of gene transcription during early mammalian embryogenesis. In addition, Brg1/hBRM also play a role as a tumor suppressors and Brg1 is mutated in several tumor cell lines (6-8).

$305
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 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 Granzyme B (D2H2F) Rabbit mAb #17215.
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Flow Cytometry

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).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: The solute carrier family 39 (zinc transporter) member 7 (SLC39A7, ZIP7) is an ER and Golgi membrane protein that regulates cellular zinc homeostasis by controlling release of zinc from these organelles to the cytoplasm (1,2). Zinc release mediated by ZIP7 results in activation of protein kinases that are involved in cell proliferation and migration (3,4). The protein kinase CK2 phosphorylates and activates ZIP7 in response to extracellular signals, such as growth factor stimulation (4,5). Increased expression of ZIP7 is observed in breast cancer tissues (6). Research studies indicate that ZIP7 is responsible for activation of multiple tyrosine kinases in aggressive, tamoxifen-resistant breast cancer (7,8).

The Inflammasome Antibody Sampler Kit provides an economical means of detecting multiple inflammasome components. The kit contains enough primary antibodies to perform at least two western blot experiments.

Background: The innate immune system works as the first line of defense in protection from pathogenic microbes and host-derived signals of cellular distress. One way in which these “danger” signals trigger inflammation is through activation of inflammasomes, which are multiprotein complexes that assemble in the cytosol after exposure to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs) and result in the activation of caspase-1 and subsequent cleavage of proinflammatory cytokines IL-1β and IL-18 (Reviewed in 1-6). Inflammasome complexes typically consist of a cytosolic pattern recognition receptor (PRR; a nucleotide-binding domain and leucine-rich-repeat [NLR] or AIM2-like receptor [ALR] family member), an adaptor protein (ASC/TMS1), and pro-caspase-1. A number of distinct inflammasome complexes have been identified, each with a unique PRR and activation triggers. The best characterized is the NLRP3 complex, which contains NLRP3, ASC/TMS1, and pro-caspase-1. The NLRP3 inflammasome is activated in a two-step process. First, NF-κB signaling is induced through PAMP- or DAMP-mediated activation of TLR4 or TNFR, resulting in increased expression of NLRP3, pro-IL-1β, and pro-IL-18 (priming step, signal 1). Next, indirect activation of NLRP3 occurs by a multitude of signals (whole pathogens, PAMPs/DAMPs, potassium efflux, lysosomal-damaging environmental factors [uric acid, silica, alum] and endogenous factors [amyloid-β, cholesterol crystals], and mitochondrial damage), leading to complex assembly and activation of caspase-1 (signal 2). The complex inflammasome structure is built via domain interactions among the protein components. Other inflammasomes are activated by more direct means: double-stranded DNA activates the AIM2 complex, anthrax toxin activates NLRP1, and bacterial flagellin activates NLRC4. Activated caspase-1 induces secretion of proinflammatory cytokines IL-1β and -18, but also regulates metabolic enzyme expression, phagosome maturation, vasodilation, and pyroptosis, an inflammatory programmed cell death. Inflammasome signaling contributes to the onset of a number of diseases, including atherosclerosis, type II diabetes, Alzheimer’s disease, and autoimmune disorders.

PTMScan® Technology employs a proprietary methodology from Cell Signaling Technology (CST) for peptide enrichment by immunoprecipitation using a specific bead-conjugated antibody in conjunction with liquid chromatography (LC) tandem mass spectrometry (MS/MS) for quantitative profiling of post-translational modification (PTM) sites in cellular proteins. These include phosphorylation (PhosphoScan®), ubiquitination (UbiScan®), acetylation (AcetylScan®), and methylation (MethylScan®), among others. PTMScan® Technology enables researchers to isolate, identify, and quantitate large numbers of post-translationally modified cellular peptides with a high degree of specificity and sensitivity, providing a global overview of PTMs in cell and tissue samples without preconceived biases about where these modified sites occur. For more information on PTMScan® Proteomics Services, please visit https://www.cellsignal.com/services/index.html.
$489
96 assays
1 Kit
The PathScan® Total YAP Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of YAP protein. A YAP rabbit mAb has been coated onto the microwells. After incubation with cell lysates, the YAP protein is captured by the coated antibody. Following extensive washing, YAP mouse detection mAb is added to detect captured YAP protein. Anti-mouse, HRP-linked antibody is then used to recognize the bound detection antibody. HRP substrate, TMB, is added to develop color. The magnitude of absorbance for the developed color is proportional to the quantity of YAP protein.Antibodies in the kit are custom formulations specific to the kit.
REACTIVITY
Human, Mouse

Background: YAP (Yes-associated protein, YAP65) was identified based on its ability to associate with the SH3 domain of Yes. It also binds to other SH3 domain-containing proteins such as Nck, Crk, Src, and Abl (1). In addition to the SH3 binding motif, YAP contains a PDZ interaction motif, a coiled-coil domain, and WW domains (2-4). While initial studies of YAP all pointed towards a role in anchoring and targeting to specific subcellular compartments, subsequent studies showed that YAP is a transcriptional co-activator by virtue of its WW domain interacting with the PY motif (PPxY) of the transcription factor PEBP2 and other transcription factors (5). In its capacity as a transcriptional co-activator, YAP is now widely recognized as a central mediator of the Hippo Pathway, which plays a fundamental and widely conserved role in regulating tissue growth and organ size. Phosphorylation at multiple sites (e.g., Ser109, Ser127) by LATS kinases promotes YAP translocation from the nucleus to the cytoplasm, where it is sequestered through association with 14-3-3 proteins (6-8). These LATS-driven phosphorylation events serve to prime YAP for subsequent phosphorylation by CK1δ/ε in an adjacent phosphodegron, triggering proteosomal degradation of YAP (9).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human

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

Background: The annexin superfamily consists of 13 calcium or calcium and phospholipid binding proteins with high biological and structural homology (1). Annexin-1 (ANXA1) is the first characterized member of the annexin family of proteins and is able to bind to cellular membranes in a calcium-dependent manner, promoting membrane fusion and endocytosis (2-4). Annexin A1 has anti-inflammatory properties and inhibits phospholipase A2 activity (5,6). Annexin A1 can accumulate on internalized vesicles after EGF-stimulated endocytosis and may be required for a late stage in inward vesiculation (7). Phosphorylation by PKC, EGFR, and Chak1 results in inhibition of annexin A1 function (8-10). Annexin A1 has also been identified as one of the 'eat-me' signals on apoptotic cells that are to be recognized and ingested by phagocytes (11). Annexin A1, as an endogenous anti-inflammatory mediator, has roles in many diverse cellular functions, such as membrane aggregation, inflammation, phagocytosis, proliferation, apoptosis, and tumorigenesis and cancer development (12-14).

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

Application Methods: Western Blotting

Background: Heme oxygenases (HMOX or HO) catalyze the rate-limiting step of the oxidative degradation of heme into iron, carbon monoxide, and biliverdin (1). Biliverdin is then converted to bilirubin (2). Heme is a strong pro-oxidant whereas bilirubin is a strong antioxidant (2). Research studies suggest disregulation of heme oxygenases may contribute to oxidative stress-related diseases (2). There are three isozymes of heme oxygenases: HMOX1/HO-1, HMOX2/HO-2, and HMOX3/HO-3 (1,2). HMOX1/HO-1 is inducible by heme and other stress stimuli (1,3). HMOX2/HO-2 and HMOX3/HO-3 are constitutively expressed (1,3).

$108
250 PCR reactions
500 µl
SimpleChIP® Human KLK3 Promoter Primers contain a mix of forward and reverse PCR primers that are specific to a region of the human kallikrein-related peptidase 3 promoter. These primers can be used to amplify DNA that has been isolated using chromatin immunoprecipitation (ChIP). Primers have been optimized for use in SYBR® Green quantitative real-time PCR and have been tested in conjunction with SimpleChIP® Enzymatic Chromatin IP Kits #9002 and #9003 and ChIP-validated antibodies from Cell Signaling Technology®.
REACTIVITY
Human

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

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunofluorescence (Immunocytochemistry)

Background: Mammalian cells synthesize serine de novo by diverting a portion of the glycolytic intermediate 3-phosphoglycerate into the phosphorylated pathway of serine synthesis. This shift supports anabolism by providing precursors for the biosynthesis of proteins, nucleotides, creatine, porphyrins, phospholipids, and glutathione. Phosphoglycerate dehydrogenase (PHGDH) catalyzes the first step in the serine biosynthesis pathway by converting 3-phosphoglycerate into phosphohydroxy pyruvate (1).Research studies demonstrate that an increase in serine biosynthesis supports growth and proliferation of cancer cells (2-4), which is supported by amplification and overexpression of PHGDH in a subset of melanoma and breast cancers (5,6). Suppression of PHGDH expression in cell lines with elevated PHGDH levels causes a strong decrease in cell proliferation and inhibits tumor growth in vivo (5). Additional evidence suggests that PHGDH interacts with and stabilizes FoxM1, which promotes the proliferation, invasion, and tumorigenicity of glioma cells (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: Aminopeptidase N (APN, CD13) is a widely expressed, membrane-bound proteolytic enzyme that breaks down peptides during digestion, cleaves cell surface antigens during antigen presentation, and acts as a receptor for human viruses, including several coronaviruses. This multifunctional protein is implicated in the regulation of many biological processes, including angiogenesis, cell proliferation, cell migration, inflammation and immune response (1,2). APN was originally identified as the cell surface antigen CD13, which is expressed in myeloid lineage hematopoietic cells and myeloid leukemia (3). Identified substrates of aminopeptidase N include the angiotensin I-III peptide hormones, the opioid peptide met-enkephalin, and cytokines MCP-1 and MIP-1 (4). Abnormal APN protein expression is seen in various forms of cancer, with high APN expression associated with poor survival in colon cancer and non-small cell lung cancer and silenced APN expression related to poor prognosis in prostate cancer (5-7).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Immunohistochemistry (Paraffin), Western Blotting

Background: VCAM-1 (vascular cell adhesion molecule-1) is a transmembrane glycoprotein containing multiple amino-terminal extracellular Ig-like domains, a transmembrane domain, and a short carboxy-terminal cytoplasmic domain (1). Alternative splicing generates two isoforms of VCAM-1 (2). The role of VCAM-1 during infection and inflammatory diseases is well characterized. Expression of VCAM-1 is induced in endothelial cells by inflammatory cytokines including TNF-α and IL-1β (1). VCAM-1 on endothelial cells interacts with the integrin VLA-4 (α4β1) on leukocytes to mediate migration of circulating leukocytes from the blood across the endothelium and into tissues (3).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

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

Background: PARP, a 116 kDa nuclear poly (ADP-ribose) polymerase, appears to be involved in DNA repair in response to environmental stress (1). This protein can be cleaved by many ICE-like caspases in vitro (2,3) and is one of the main cleavage targets of caspase-3 in vivo (4,5). In human PARP, the cleavage occurs between Asp214 and Gly215, which separates the PARP amino-terminal DNA binding domain (24 kDa) from the carboxy-terminal catalytic domain (89 kDa) (2,4). PARP helps cells to maintain their viability; cleavage of PARP facilitates cellular disassembly and serves as a marker of cells undergoing apoptosis (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse, Rat

Application Methods: Chromatin IP, Immunoprecipitation, 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).

$305
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct immuno fluorescence analysis in mouse tissue. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated TBR1 (D6C6X) Rabbit mAb #49661.
APPLICATIONS
REACTIVITY
Mouse

Application Methods: Immunofluorescence (Frozen)

Background: T-box, brain, 1 (TBR1) is a transcription factor important in vertebrate embryo development. As a member of T-Box family of transcription factors, TBR1 is expressed in postmitotic glutamatergic projection neurons (1). During cortical neurogenesis, sequential expression of transcription factors Pax6, TBR2, and TBR1 regulates discrete steps in projection neuron differentiation (2). TBR1 is enriched in layer 6 of the developing cortex. In the absence of TBR1, TBR1 mutants exhibit profound defects in frontal cortex and layer 6 differentiation, suggesting that TBR1 regulates regional and laminar identity of postmitotic cortical neurons (3). Therefore, TBR1 expression can be used as a marker for postmitotic glutamatergic neurons and cortical laminar specificity.

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: Sphingosine kinases (SPHKs) catalyze the phosphorylation of sphingosine to form sphingosine-1-phosphate (S1P), a lipid mediator with both intra- and extracellular functions. Together with other sphingolipid metabolizing enzymes, SPHKs regulate the balance of the lipid mediators, ceramide, sphingosine, and S1P (1-4). Two distinct SPHK isoforms, SPHK1 and SPHK2, have been cloned and characterized (5,6). SPHK1 and SPHK2 are highly conserved and diversely expressed (7,8). The SPHKs are activated by G protein-coupled receptors, receptor tyrosine kinases, immunoglobulin receptors, cytokines, and other stimuli (9-12). The molecular mechanisms by which SPHK1 and SPHK2 are specifically regulated are complex and only partially understood.

The Autophagy Vesicle Elongation (Atg12 Conjugation) Antibody Sampler Kit provides an economical means of detecting proteins related to autophagy vesicle elongation pathway. The kit contains enough antibody to perform two western blot experiments per primary antibody.
$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 700 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 CD45 (D9M8I) XP® Rabbit mAb #13917.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

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).

$305
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to PerCP-Cy5.5® and tested in-house for direct flow cytometric analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

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).

$305
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. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated CDK9 (C12F7) Rabbit mAb #2316.
APPLICATIONS
REACTIVITY
Bovine, Dog, Hamster, Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry

Background: P-TEFb is a general transcription factor that regulates transcription elongation through phosphorylation of the C-terminal tail domain (CTD) of RNA polymerase II (RNAP II). The P-TEFb complex is composed of a catalytic subunit, CDK9, and its regulatory cyclin partner, which can be cyclin T1, T2a, T2b or K (reviewed in 1,2). P-TEFb is recruited by the HIV Tat protein to allow transcriptional elongation, and subsequent replication of the viral genome. Inhibition of P-TEFb function therefore has potential for HIV therapy. CDK9 exists as two isoforms, an abundant 42 kDa isoform, and a less abundant 55 kDa isoform, which contains an amino-terminal extension (3). The two forms likely have distinct purposes based on differential expression during lymphocyte activation (4,5) and on their localization within the nucleus (5).Cyclin dependent kinases (CDKs) are activated in part by cyclin binding and by phosphorylation of a conserved threonine in the T-loop domain. Phosphorylation of CDK9 at the T-loop Thr186 by an unidentified nuclear kinase may be important in P-TEFb activation (6) and regulation of HIV transcription (7). Acetylation of CDK9 at Lys44 affects its ability to phosphorylate the RNAPII CTD (8).

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

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

Background: Endothelial nitric-oxide synthase (eNOS) is an important enzyme in the cardiovascular system. It catalyzes the production of nitric oxide (NO), a key regulator of blood pressure, vascular remodeling, and angiogenesis (1,2). The activity of eNOS is regulated by phosphorylation at multiple sites. The two most thoroughly studied sites are the activation site Ser1177 and the inhibitory site Thr495 (3). Several protein kinases including Akt/PKB, PKA, and AMPK activate eNOS by phosphorylating Ser1177 in response to various stimuli (4,5). In contrast, bradykinin and H2O2 activate eNOS activity by promoting both Ser1177 phosphorylation and Thr495 dephosphorylation (6,7).

$254
100 tests
500 µl
This Cell Signaling Technology antibody is conjugated to APC and tested in-house for direct flow cytometry analysis in human cells.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: CD19 is a 95 kDa coreceptor, which amplifies the signaling cascade in B cells (1). On the B cell surface, CD19 associates with CD21, CD81 and Leu-13 to exert its function. The cytoplasmic tail of CD19 has nine conserved tyrosine residues playing critical roles in CD19 mediated function by coupling signaling molecules to the receptor (1). After B cell receptor or CD19 ligation, Tyr531 and Tyr500 of CD19 are progressively phosphorylated. This phosphorylation enables the coupling of PI3 kinase and Src family tyrosine kinase to CD19 and activates the PI3K and Src signaling pathways (2,3). Coligation of B cell receptor and CD19 also promotes Tyr409 phosphorylation in CD19. The phosphorylation at these sites enables its binding to Vav and mediates elevated intracellular calcium response, as well as the JNK pathway (4,5).

$260
100 µl
APPLICATIONS
REACTIVITY
Mouse, Rat

Application Methods: Immunofluorescence (Frozen)

Background: Ghrelin, also known as appetite-regulating hormone, is a neuropeptide hormone belonging to the motilin family. It is the ligand for the growth hormone secretagogue receptor type 1 (GHS-R), expressed by cells in the hypothalamic ventromedial nucleus and arcuate nucleus (1). Ghrelin is synthesized as a preprohormone by ghrelinergic cells in the gastrointestinal tract; proteolytic cleavage yields a 28-amino acid peptide hormone, which undergoes obligate n-octanoylation at serine 3 by the enzyme ghrelin O-acetyltransferase (GOAT) (2). Binding of n-octanoyl ghrelin to GHS-R stimulates growth hormone release, while simultaneously exerting multiple neuroendocrine affects that influence appetite, gastric motility and energy balance (3).

$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 Di-Methyl-Histone H3 (Lys4) (C64G9) Rabbit mAb #9725.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry

Background: The nucleosome, made up of four core histone proteins (H2A, H2B, H3, and H4), is the primary building block of chromatin. Originally thought to function as a static scaffold for DNA packaging, histones have now been shown to be dynamic proteins, undergoing multiple types of post-translational modifications, including acetylation, phosphorylation, methylation, and ubiquitination (1). Histone methylation is a major determinant for the formation of active and inactive regions of the genome and is crucial for the proper programming of the genome during development (2,3). Arginine methylation of histones H3 (Arg2, 17, 26) and H4 (Arg3) promotes transcriptional activation and is mediated by a family of protein arginine methyltransferases (PRMTs), including the co-activators PRMT1 and CARM1 (PRMT4) (4). In contrast, a more diverse set of histone lysine methyltransferases has been identified, all but one of which contain a conserved catalytic SET domain originally identified in the Drosophila Su(var)3-9, Enhancer of zeste, and Trithorax proteins. Lysine methylation occurs primarily on histones H3 (Lys4, 9, 27, 36, 79) and H4 (Lys20) and has been implicated in both transcriptional activation and silencing (4). Methylation of these lysine residues coordinates the recruitment of chromatin modifying enzymes containing methyl-lysine binding modules such as chromodomains (HP1, PRC1), PHD fingers (BPTF, ING2), tudor domains (53BP1), and WD-40 domains (WDR5) (5-8). The discovery of histone demethylases such as PADI4, LSD1, JMJD1, JMJD2, and JHDM1 has shown that methylation is a reversible epigenetic marker (9).