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Product listing: VWF (D8L8G) XP® Rabbit mAb, UniProt ID P04275 #65707 to Phospho-p53 (Ser33) Antibody, UniProt ID P04637 #2526

$129
20 µl
$303
100 µl
APPLICATIONS
REACTIVITY
Human

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

Background: VWF (Von Willebrand factor) is a multimeric plasma glycoprotein that promotes adhesion of platelets to sites of vascular injury (1). Mature circulating VWF is made up of disulfide-bonded multimers that are in a complex with factor VIII (2). VWF is stored in secretory Weibel-Palade bodies in endothelial cells (3,4). It is synthesized as a large precursor protein and undergoes extensive posttranslational modifications including dimerization in the endoplasmic reticulum followed by cleavage of the pro-peptide and multimerization in the Golgi apparatus (3,4). VWF is important in hemostasis, and genetic defects in the structure and modification of VWF can cause von Willebrand disease (VWD), the most common congenital bleeding disorder in humans (5).  Alternatively, increased levels of VWF have been shown to be involved in acute coronary thrombosis and are a clinical risk marker for atherosclerosis (6). VWF has also been shown to have a role in inflammation, functioning as an adhesive site for a variety of leukocyte subsets (7). Through siRNA experiments and the use VWF-deficient mice, it has also been shown that VWF regulates angiogenesis (8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: GLI was first identified as a gene amplified in a malignant glioma (1) capable of transforming primary cells in cooperation with adenovirus E1A (2). GLI belongs to the Kruppel family of zinc finger proteins that includes three mammalian GLI proteins: GLI1, GLI2, and GLI3 (3). These GLI proteins are similar to the Drosophila homolog Cubitus interruptus (Ci) and function as transcription factors activated by the Hedgehog signaling pathway. Hedgehog signaling plays an important role in animal development, and research studies have shown that this pathway is aberrantly activated in many types of cancers (4,5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: 2’-5’-oligoadenylate synthetase 1 (OAS1) is an antiviral protein induced by type 1 interferon that plays a key role in the cellular innate immune response (1). The OAS family of proteins includes OAS1, OAS2, OAS3, and OASL in humans (2). The OAS1 enzyme produces the second messenger 2’-5’-linked oligoadenylate in response to cytosolic dsRNA. These 2’-5’-linked oligoadenylates bind to the ribonuclease RNase L, which then degrades viral and cellular RNA (3). Research studies indicate that the OAS1 system inhibits protein synthesis and induces apoptosis in virally infected cells, which limits viral infection (4). Alternative splicing generates multiple isoforms of human OAS1, including p41 and the canonical p46 (5,6). Polymorphisms in the corresponding OAS1 gene have been examined for possible association with increased susceptibility to type 1 diabetes mellitus, multiple sclerosis, and infection by viral pathogens (7,8).

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

Application Methods: Western Blotting

Background: Nod1/CARD4 is a cytosolic protein structually related to Apaf-1 and plant drug-resistance proteins that has been implicated in apoptosis and inflammatory responses to certain pathogenic bacteria (1-3). It contains an amino-terminal caspase recruitment domain (CARD) that is linked to a central nucleotide-binding domain (NBD; also known as a NOD domain) and is followed by carboxy-terminal leucine-rich repeats (LRR) (1). Like Apaf-1, Nod1 induces apoptosis by a CARD/NBD-dependent activation of caspase-9 (1). The primary function of Nod1 is thought to be as a sensor for certain pathogenic microbes and triggering inflammatory responses including the activation of NF-κB and JNK pathways (4-6). The LRR of Nod1 appears to be involved in recognition of microbial components and the CARD domain induces NF-κB activation in cooperation with the CARD containing kinase, RICK/RIP2/CARDIAK (1,5,6). Mutations in Nod1 have been linked increased susceptibility to asthma (7) and inflammatory bowel disease (8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Low density lipoprotein receptor related protein 1 ( LRP1) is a type I transmembrane receptor that mediates the endocytosis of various ligands (1). LRP1 plays important roles in lipid homeostasis, signaling transduction, embryonic development, and glucose metabolism (2-6). In addition, LRP1 regulates APP processing and facilitates the clearance of beta-amyloid (7-9). This finding makes LRP1 a potential therapeutic target for Alzheimer’s disease. LRP1 preprotein is proteolytically processed by furin to generate a 515 kDa extracellular α subunit and a membrane-anchored 85 kDa β subunit, which together form the mature receptor (10).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Activating molecule in Beclin1-regulated autophagy (Ambra1) is a WD40-containing protein expressed during neurodevelopment that is required for neural tube development and autophagy (1). Several studies have identified interactions between Ambra1 with regulators of autophagy and apoptosis (reviewed in 2). Ambra1 was originally found to interact with Beclin-1, a key protein responsible for activating the class III PI3K Vps34 (1). Further studies showed that Ambra1 tethers the Beclin-1-Vps34 complex to the cytoskeletal network through dynein light chains and that during autophagy ULK1 phosphorylates Ambra1, resulting in disassociation with dynein and translocation of the Beclin-Vps34 complex to the endoplasmic reticulum to initiate autophagosome formation (3,4). In addition, it has been found that Ambra1 binds to mitochondrial Bcl-2 and that this interaction is regulated by either apoptosis or autophagy (5,6). Ambra1 also interacts with Parkin, an E3 ubiquitin ligase important for mitophagy, a selective autophagic process of mitochondrial clearance (7,8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Bad is a proapoptotic member of the Bcl-2 family that promotes cell death by displacing Bax from binding to Bcl-2 and Bcl-xL (1,2). Survival factors, such as IL-3, inhibit the apoptotic activity of Bad by activating intracellular signaling pathways that result in the phosphorylation of Bad at Ser112 and Ser136 (2). Phosphorylation at these sites promotes binding of Bad to 14-3-3 proteins to prevent an association between Bad with Bcl-2 and Bcl-xL (2). Akt phosphorylates Bad at Ser136 to promote cell survival (3,4). Bad is phosphorylated at Ser112 both in vivo and in vitro by p90RSK (5,6) and mitochondria-anchored PKA (7). Phosphorylation at Ser155 in the BH3 domain by PKA plays a critical role in blocking the dimerization of Bad and Bcl-xL (8-10).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: The 26S proteasome is a highly abundant proteolytic complex involved in the degradation of ubiquitinated substrate proteins. It consists largely of two sub-complexes, the 20S catalytic core particle (CP) and the 19S/PA700 regulatory particle (RP) that can cap either end of the CP. The CP consists of two stacked heteroheptameric β-rings (β1-7) that contain three catalytic β-subunits and are flanked on either side by two heteroheptameric α-rings (α1-7). The RP includes a base and a lid, each having multiple subunits. The base, in part, is composed of a heterohexameric ring of ATPase subunits belonging to the AAA (ATPases Associated with diverse cellular Activities) family. The ATPase subunits function to unfold the substrate and open the gate formed by the α-subunits, thus exposing the unfolded substrate to the catalytic β-subunits. The lid consists of ubiquitin receptors and DUBs that function in recruitment of ubiquitinated substrates and modification of ubiquitin chain topology (1,2). Other modulators of proteasome activity, such as PA28/11S REG, can also bind to the end of the 20S CP and activate it (1,2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: PTPN22 (Lyp/PEP) is a cytoplasmic phosphatase expressed by hematopoietic cells (1,2). PTPN22 associates with the tyrosine kinase Csk to inhibit T cell receptor signaling through inactivation of Src kinases (3,4). Csk phosphorylates Src kinases on an inhibitory tyrosine, while PTPN22 dephosphorylates an activating site (4). PTPN22(-/-) mice have higher levels of activated Lck than wild-type, resulting in greater T cell expansion and increased serum antibody levels (5). Research studies have shown that a single-nucleotide polymorphism, 1858T of the PTPN22 gene which encodes the amino acid substitution R620W, confers increased risk for multiple autoimmune diseases including type I diabetes, rheumatoid arthritis, systemic lupus erythematosus, and Graves disease (6-9). Interestingly, although the R620W substitution disrupts the interaction between Csk and PTPN22, it is actually a gain-of-function mutation resulting in increased phosphatase activity (6,10,11). Recent evidence suggests that the autoimmune phenotype associated with the R620W variant is the result of increased calpain-mediated degradation and decreased protein levels of PTPN22 (12).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

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

Background: Paired box (PAX) proteins are a family of transcription factors that play important and diverse roles in animal development (1). Nine PAX proteins (PAX1-9) have been described in humans and other mammals. They are defined by the presence of an amino-terminal "paired" domain, consisting of two helix-turn-helix motifs, with DNA binding activity (2). PAX proteins are classified into four structurally distinct subgroups (I-IV) based on the absence or presence of a carboxy-terminal homeodomain and a central octapeptide region. Subgroup I (PAX1 and 9) contains the octapeptide but lacks the homeodomain; subgroup II (PAX2, 5, and 8) contains the octapeptide and a truncated homeodomain; subgroup III (PAX3 and 7) contains the octapeptide and a complete homeodomain; and subgroup IV (PAX4 and 6) contains a complete homeodomain but lacks the octapeptide region (2). PAX proteins play critically important roles in development by regulating transcriptional networks responsible for embryonic patterning and organogenesis (3); a subset of PAX proteins also maintain functional importance during postnatal development (4). Research studies have implicated genetic mutations that result in aberrant expression of PAX genes in a number of cancer subtypes (1-3), with members of subgroups II and III identified as potential mediators of tumor progression (2).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Autophagy is a catabolic process for the autophagosomic-lysosomal degradation of bulk cytoplasmic contents. Control of autophagy was largely discovered in yeast and involves proteins encoded by a set of autophagy-related genes (Atg) (1). Formation of autophagic vesicles requires a pair of essential ubiquitin-like conjugation systems, Atg12-Atg5 and Atg8-phosphatidylethanolamine (Atg8-PE), which are widely conserved in eukaryotes (2). Numerous mammalian counterparts to yeast Atg proteins have been described, including three Atg8 proteins (GATE-16, GABARAP, and LC3) and four Atg4 homologs (Atg4A/autophagin-2, Atg4B/autophagin-1, Atg4C/autophagin-3, and Atg4D/autophagin-4) (3-5). The cysteine protease Atg4 is pivotal to autophagosome membrane generation and regulation. Atg4 primes the Atg8 homolog for lipidation by cleaving its carboxy terminus and exposing its glycine residue for E1-like enzyme Atg7. The Atg8 homolog is transferred to the E2-like enzyme Atg3 before forming the Atg8-PE conjugate. During later stages of autophagy, Atg4 can reverse this lipidation event by cleaving PE, thereby recycling the Atg8 homolog (6).

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

Application Methods: Western Blotting

Background: Pim proteins (Pim-1, Pim-2 and Pim-3) are oncogene-encoded serine/threonine kinases (1). Pim-1, a serine/threonine kinase highly expressed in hematopoietic cells, plays a critical role in the transduction of mitogenic signals and is rapidly induced by a variety of growth factors and cytokines (1-4). Pim-1 cooperates with c-Myc in lymphoid cell transformation and protects cells from growth factor withdrawal and genotoxic stress-induced apoptosis (5,6). Pim-1 also enhances the transcriptional activity of c-Myb through direct phosphorylation within the c-Myb DNA binding domain as well as phosphorylation of the transcriptional coactivator p100 (7,8). Hypermutations of the Pim-1 gene are found in B-cell diffuse large cell lymphomas (9). Phosphorylation of Pim-1 at Tyr218 by Etk occurs following IL-6 stimulation and correlates with an increase in Pim-1 activity (10). Various Pim substrates have been identified; Bad is phosphorylated by both Pim-1 and Pim-2 at Ser112 and this phosphorylation reverses Bad-induced cell apoptosis (11,12).

$232
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 647 fluorescent dye and tested in-house for direct flow cytometry in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated PD-L1 (E1L3N®) XP® Rabbit mAb #13684.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: Programmed cell death 1 ligand 1 (PD-L1, B7-H1, CD274) is a member of the B7 family of cell surface ligands that regulate T cell activation and immune responses. The PD-L1 ligand binds the PD-1 transmembrane receptor and inhibits T cell activation. PD-L1 was discovered following a search for novel B7 protein homologs and was later shown to be expressed by antigen presenting cells, activated T cells, and tissues including placenta, heart, and lung (1-3). Similar in structure to related B7 family members, PD-L1 protein contains extracellular IgV and IgC domains and a short, cytoplasmic region. Research studies demonstrate that PD-L1 is expressed in several tumor types, including melanoma, ovary, colon, lung, breast, and renal cell carcinomas (4-6). Expression of PD-L1 in cancer is associated with tumor infiltrating lymphocytes, which mediate PD-L1 expression through the release of interferon gamma (7). Additional research links PD-L1 expression to cancers associated with viral infections (8,9).

$131
1 ml
This Cell Signaling Technology antibody is immobilized via covalent binding of primary amino groups to N-hydroxysuccinimide (NHS)-activated Sepharose® beads. Anti-rabbit IgG F(ab') 2 Fragment (Sepharose® Bead Conjugate) is useful for the immunoprecipitation of antibodies raised in rabbit.
APPLICATIONS

Application Methods: Immunoprecipitation

Each control slide contains formalin fixed, paraffin-embedded LNCaP cells, both untreated and treated with PI3-Kinase inhibitor LY294002, that serve as a control for Phospho-Akt (Ser473) immunostaining. Western blot analysis was performed on extracts derived from the same cells to verify the efficacy of the LY942002 treatment.To be used with antibodies: 2855, 9644, 4060, 3787, 2938, 4691, 4685, 2920, 9323, 5482, 5196, 2997, 2691, 4858, 4857, 2211, 5364, 2217, 2317.

Background: Akt, also referred to as PKB or Rac, plays a critical role in controlling survival and apoptosis (1-3). This protein kinase is activated by insulin and various growth and survival factors to function in a wortmannin-sensitive pathway involving PI3 kinase (2,3). Akt is activated by phospholipid binding and activation loop phosphorylation at Thr308 by PDK1 (4) and by phosphorylation within the carboxy terminus at Ser473. The previously elusive PDK2 responsible for phosphorylation of Akt at Ser473 has been identified as mammalian target of rapamycin (mTOR) in a rapamycin-insensitive complex with rictor and Sin1 (5,6). Akt promotes cell survival by inhibiting apoptosis through phosphorylation and inactivation of several targets, including Bad (7), forkhead transcription factors (8), c-Raf (9), and caspase-9. PTEN phosphatase is a major negative regulator of the PI3 kinase/Akt signaling pathway (10). LY294002 is a specific PI3 kinase inhibitor (11). Another essential Akt function is the regulation of glycogen synthesis through phosphorylation and inactivation of GSK-3α and β (12,13). Akt may also play a role in insulin stimulation of glucose transport (12). In addition to its role in survival and glycogen synthesis, Akt is involved in cell cycle regulation by preventing GSK-3β-mediated phosphorylation and degradation of cyclin D1 (14) and by negatively regulating the cyclin dependent kinase inhibitors p27 Kip1 (15) and p21 Waf1/Cip1 (16). Akt also plays a critical role in cell growth by directly phosphorylating mTOR in a rapamycin-sensitive complex containing raptor (17). More importantly, Akt phosphorylates and inactivates tuberin (TSC2), an inhibitor of mTOR within the mTOR-raptor complex (18,19).

The 4E-BP Antibody Sampler Kit provides an economical means to investigate regulation of cap-dependent translation within the cell. The kit contains primary and secondary antibodies to perform two Western blots with each antibody.

Background: Translation repressor protein 4E-BP1 (also known as PHAS-1) inhibits cap-dependent translation by binding to the translation initiation factor eIF4E. Hyperphosphorylation of 4E-BP1 disrupts this interaction and results in activation of cap-dependent translation (1). Both the PI3 kinase/Akt pathway and FRAP/mTOR kinase regulate 4E-BP1 activity (2,3). Multiple 4E-BP1 residues are phosphorylated in vivo (4). While phosphorylation by FRAP/mTOR at Thr37 and Thr46 does not prevent the binding of 4E-BP1 to eIF4E, it is thought to prime 4E-BP1 for subsequent phosphorylation at Ser65 and Thr70 (5).

$305
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Neurofilament-L (C28E10) Rabbit mAb #2837.
APPLICATIONS
REACTIVITY
Mouse, Rat

Application Methods: Immunofluorescence (Frozen)

Background: The cytoskeleton consists of three types of cytosolic fibers: actin microfilaments, intermediate filaments, and microtubules. Neurofilaments are the major intermediate filaments found in neurons and consist of light (NFL), medium (NFM), and heavy (NFH) subunits (1). Similar in structure to other intermediate filament proteins, neurofilaments have a globular amino-terminal head, a central α-helical rod domain, and a carboxy-terminal tail. A heterotetrameric unit (NFL-NFM and NFL-NFH) forms a protofilament, with eight protofilaments comprising the typical 10 nm intermediate filament (2). While neurofilaments are critical for radial axon growth and determine axon caliber, microtubules are involved in axon elongation. PKA phosphorylates the head domain of NFL and NFM to inhibit neurofilament assembly (3,4). Research studies have shown neurofilament accumulations in many human neurological disorders including Parkinson's disease (in Lewy bodies along with α-synuclein), Alzheimer's disease, Charcot-Marie-Tooth disease, and Amyotrophic Lateral Sclerosis (ALS) (1).

$364
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin in combination with cyanine 7 (PE-Cy®7) 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 Phospho-S6 Ribosomal Protein (Ser235/236) (D57.2.2E) XP® Rabbit mAb #4858.
APPLICATIONS
REACTIVITY
Human, Mink, Monkey, Mouse, Rat, S. cerevisiae

Application Methods: Flow Cytometry

Background: One way that growth factors and mitogens effectively promote sustained cell growth and proliferation is by upregulating mRNA translation (1,2). Growth factors and mitogens induce the activation of p70 S6 kinase and the subsequent phosphorylation of the S6 ribosomal protein. Phosphorylation of S6 ribosomal protein correlates with an increase in translation of mRNA transcripts that contain an oligopyrimidine tract in their 5' untranslated regions (2). These particular mRNA transcripts (5'TOP) encode proteins involved in cell cycle progression, as well as ribosomal proteins and elongation factors necessary for translation (2,3). Important S6 ribosomal protein phosphorylation sites include several residues (Ser235, Ser236, Ser240, and Ser244) located within a small, carboxy-terminal region of the S6 protein (4,5).

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-SAPK/JNK (Thr183/Tyr185) (G9) Mouse mAb #9255. 
APPLICATIONS
REACTIVITY
Hamster, Human, Mouse, Rat, S. cerevisiae

Application Methods: Flow Cytometry

Background: The stress-activated protein kinase/Jun-amino-terminal kinase SAPK/JNK is potently and preferentially activated by a variety of environmental stresses including UV and gamma radiation, ceramides, inflammatory cytokines, and in some instances, growth factors and GPCR agonists (1-6). As with the other MAPKs, the core signaling unit is composed of a MAPKKK, typically MEKK1-MEKK4, or by one of the mixed lineage kinases (MLKs), which phosphorylate and activate MKK4/7. Upon activation, MKKs phosphorylate and activate the SAPK/JNK kinase (2). Stress signals are delivered to this cascade by small GTPases of the Rho family (Rac, Rho, cdc42) (3). Both Rac1 and cdc42 mediate the stimulation of MEKKs and MLKs (3). Alternatively, MKK4/7 can be activated in a GTPase-independent mechanism via stimulation of a germinal center kinase (GCK) family member (4). There are three SAPK/JNK genes each of which undergoes alternative splicing, resulting in numerous isoforms (3). SAPK/JNK, when active as a dimer, can translocate to the nucleus and regulate transcription through its effects on c-Jun, ATF-2, and other transcription factors (3,5).

$348
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 555 fluorescent dye and tested in-house for immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Vimentin (D21H3) XP® Rabbit mAb #5741.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry)

Background: The cytoskeleton consists of three types of cytosolic fibers: microfilaments (actin filaments), intermediate filaments, and microtubules. Major types of intermediate filaments are distinguished by their cell-specific expression: cytokeratins (epithelial cells), glial fibrillary acidic protein (GFAP) (glial cells), desmin (skeletal, visceral, and certain vascular smooth muscle cells), vimentin (mesenchyme origin), and neurofilaments (neurons). GFAP and vimentin form intermediate filaments in astroglial cells and modulate their motility and shape (1). In particular, vimentin filaments are present at early developmental stages, while GFAP filaments are characteristic of differentiated and mature brain astrocytes. Thus, GFAP is commonly used as a marker for intracranial and intraspinal tumors arising from astrocytes (2). Research studies have shown that vimentin is present in sarcomas, but not carcinomas, and its expression is examined in conjunction with that of other markers to distinguish between the two (3). Vimentin's dynamic structural changes and spatial re-organization in response to extracellular stimuli help to coordinate various signaling pathways (4). Phosphorylation of vimentin at Ser56 in smooth muscle cells regulates the structural arrangement of vimentin filaments in response to serotonin (5,6). Remodeling of vimentin and other intermediate filaments is important during lymphocyte adhesion and migration through the endothelium (7).During mitosis, CDK1 phosphorylates vimentin at Ser56. This phosphorylation provides a PLK binding site for vimentin-PLK interaction. PLK further phosphorylates vimentin at Ser82, which might serve as memory phosphorylation site and play a regulatory role in vimentin filament disassembly (8,9). Additionally, studies using various soft-tissue sarcoma cells have shown that phosphorylation of vimentin at Ser39 by Akt1 enhances cell migration and survival, suggesting that vimentin could be a potential target for soft-tissue sarcoma targeted therapy (10,11).

$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 cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated FoxO1 (C29H4) Rabbit mAb #2880.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry

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

$293
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: Keratins (cytokeratins) are intermediate filament proteins that are mainly expressed in epithelial cells. Keratin heterodimers composed of an acidic keratin (or type I keratin, keratins 9 to 23) and a basic keratin (or type II keratin, keratins 1 to 8) assemble to form filaments (1,2). Keratin isoforms demonstrate tissue- and differentiation-specific profiles that make them useful as research biomarkers (1). Research studies have shown that mutations in keratin genes are associated with skin disorders, liver and pancreatic diseases, and inflammatory intestinal diseases (3-6).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

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

Background: Phosphoinositide-specific phospholipase C (PLC) plays a significant role in transmembrane signaling. In response to extracellular stimuli such as hormones, growth factors, and neurotransmitters, PLC hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) to generate two secondary messengers: inositol 1,4,5-triphosphate (IP3) and diacylglycerol (DAG) (1). At least four families of PLCs have been identified: PLCβ, PLCγ, PLCδ, and PLCε. Phosphorylation is one of the key mechanisms that regulate the activity of PLC. PLCγ is activated by both receptor and non-receptor tyrosine kinases (2). PLCγ forms a complex with EGF and PDGF receptors, which leads to the phosphorylation of PLCγ at Tyr771, 783, and 1248 (3). Phosphorylation by Syk at Tyr783 activates the enzymatic activity of PLCγ1 (4). PLCγ2 is engaged in antigen-dependent signaling in B cells and collagen-dependent signaling in platelets. Phosphorylation by Btk or Lck at Tyr753, 759, 1197, and 1217 is correlated with PLCγ2 activity (5,6).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: Insulin receptor substrate 1 (IRS-1) is one of the major substrates of the insulin receptor kinase (1). IRS-1 contains multiple tyrosine phosphorylation motifs that serve as docking sites for SH2-domain containing proteins that mediate the metabolic and growth-promoting functions of insulin (2-4). IRS-1 also contains over 30 potential serine/threonine phosphorylation sites. Ser307 of IRS-1 is phosphorylated by JNK (5) and IKK (6) while Ser789 is phosphorylated by SIK-2, a member of the AMPK family (7). The PKC and mTOR pathways mediate phosphorylation of IRS-1 at Ser612 and Ser636/639, respectively (8,9). Phosphorylation of IRS-1 at Ser1101 is mediated by PKCθ and results in an inhibition of insulin signaling in the cell, suggesting a potential mechanism for insulin resistance in some models of obesity (10).

$327
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to Alexa Fluor® 488 fluorescent dye and tested in-house for direct flow cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-Syk (Tyr525/526) (C87C1) Rabbit mAb #2710.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry)

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

$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 cytometry and immunofluorescent analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Btk (D3H5) Rabbit mAb #8547.
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Flow Cytometry

Background: Bruton's tyrosine kinase (Btk) is a member of the Btk/Tec family of cytoplasmic tyrosine kinases. Like other Btk family members, it contains a pleckstrin homology (PH) domain and Src homology SH3 and SH2 domains. Btk plays an important role in B cell development (1,2). Activation of B cells by various ligands is accompanied by Btk membrane translocation mediated by its PH domain binding to phosphatidylinositol-3,4,5-trisphosphate (3-5). The membrane-localized Btk is active and associated with transient phosphorylation of two tyrosine residues, Tyr551 and Tyr223. Tyr551 in the activation loop is transphosphorylated by the Src family tyrosine kinases, leading to autophosphorylation at Tyr223 within the SH3 domain, which is necessary for full activation (6,7). The activation of Btk is negatively regulated by PKCβ through phosphorylation of Btk at Ser180, which results in reduced membrane recruitment, transphosphorylation, and subsequent activation (8). The PKC inhibitory signal is likely to be a key determinant of the B cell receptor signaling threshold to maintain optimal Btk activity (8).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

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

$303
100 µl
APPLICATIONS

Application Methods: Western Blotting

Background: Lysine is subject to a wide array of regulatory post-translational modifications due to its positively charged ε-amino group side chain. The most prevalent of these are ubiquitination and acetylation, which are highly conserved among prokaryotes and eukaryotes (1,2). Acyl group transfer from the metabolic intermediates acetyl-, succinyl-, malonyl-, glutaryl-, butyryl-, propionyl-, and crotonyl-CoA all neutralize lysine’s positive charge and confer structural alterations affecting substrate protein function. Lysine acetylation is catalyzed by histone acetyltransferases, HATs, using acetyl-CoA as a cofactor (3,4). Deacylation is mediated by histone deacetylases, HDACs 1-11, and NAD-dependent Sirtuins 1-7. Some sirtuins have little to no deacetylase activity, suggesting that they are better suited for other acyl lysine substrates (5).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunohistochemistry (Paraffin), 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).