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Product listing: ENSA (D5Z1U) Rabbit mAb, UniProt ID O43768 #11915 to PSMA2 (D3A4) Rabbit mAb, UniProt ID P25787 #11864

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Western Blotting

Background: Mitotic control is important for normal growth, development, and maintenance of all eukaryotic cells. Research studies have demonstrated that inappropriate control of mitosis can lead to genomic instability and cancer (reviewed in 1,2). A regulator of mitosis, Greatwall kinase (Gwl), was first identified in Drosophila melanogaster (3). Subsequent studies showed that, based on sequence homology and function, microtubule-associated serine/threonine kinase-like (MASTL) is the human ortholog of Gwl (4). Regulation of MASTL/Gwl activation has been shown to be critical for the correct timing of mitosis. Research studies have shown that Gwl is activated by hyperphosphorylation (5). The phosphorylation of human Gwl at Thr194 and Thr207 by active cyclin B1-cdc2 leads to possible autophosphorylation at Ser875 (Ser883 in Xenopus), which stabilizes the kinase. Activated Gwl phosphorylates α-Endosulfine (ENSA) and cAMP-regulated phosphoprotein 19 (ARPP19) at Ser67 and Ser62, respectively. Phosphorylated ENSA and ARPP19 inhibit the activity of the B55 subunit-associated form of protein phosphatase 2A (PP2A-B55), allowing for complete phosphorylation of mitotic substrates by cyclin B1-cdc2 and mitotic entry. When Gwl is inactivated, PP2A-B55 reactivates, which leads to dephosphorylation of cyclin B1-cdc2 and mitotic exit (5,6, reviewed in 7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: The proprotein convertases (PCs) are enzymes that activate precursor proteins through proteolytic cleavage within the secretory pathway. PCs comprise several enzymes that are basic amino acid-specific proteinases (furin, PC1/3, PC2, PC4, PACE4, PC5/6, and PC7), as well as nonbasic amino acid convertases (S1P and PC9) (1). PCs have a common structure that includes an N-terminal signal peptide for secretory pathway targeting; a pro-domain that is thought to act as an intramolecular chaperone; a catalytic domain containing the active site; a P-domain that contributes to the overall folding of the enzyme by regulating stability, calcium-, and pH-dependence; and a C-terminal domain that interacts with the membrane (2). PCs act in a tissue- and substrate-specific fashion to generate an array of bioactive peptides and proteins from precursors, both in the brain and the periphery (3).

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

Application Methods: Immunoprecipitation, Western Blotting

Background: Chromodomain-helicase-DNA-binding domain (CHD) proteins have been identified in a variety of organisms (1,2). This family of nine proteins is divided into three separate subfamilies: subfamily I (CHD1 and CHD2), subfamily II (CHD3 and CHD4), and subfamily III (CHD5, CHD6, CHD7, CHD8, and CHD9). All CHD proteins contain two tandem amino-terminal chromodomains, a SWI/SNF-related ATPase domain, and a carboxy-terminal DNA-binding domain (1,2). The chromodomains facilitate binding to methylated lysine residues of histone proteins and confer interactions with specific regions of chromatin. The SWI/SNF-related ATPase domain utilizes energy from ATP hydrolysis to modify chromatin structure. CHD proteins are often found in large, multiprotein complexes with their transcriptional activation or repression activity governed by other proteins within the complex. CHD3 (also known as Mi2-α) and CHD4 (also known as Mi2-β) are central components of the nucleosome remodeling and histone deacetylase (NuRD) transcriptional repressor complex, which also contains HDAC1, HDAC2, RBAP48, RBAP46, MTA1, MTA2, MTA3, and MBD3 (3-8). Both CHD3 and CHD4 contain two plant homeodomain (PHD) zinc finger domains that bind directly to HDAC1 and HDAC2.

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

Application Methods: Immunoprecipitation, Western Blotting

Background: NFI-C belongs to the nuclear factor I (NFI) family of site-specific transcription factors that regulate viral DNA replication and expression of various genes (1,2). The NFI family is composed of four members in vertebrates: NFI-A, NFI-B, NFI-C, and NFI-X, all of which are critical in the development of multiple organ systems in mice and humans (3). NFI-C is expressed in various tissues and regulates TGF-β dependent tooth development and hair follicle cycling (3-5). Research studies have shown that NFI-C directly represses FoxF1 transcription and suppresses the motility and invasiveness of breast cancer cells (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: The Ewing sarcoma (EWS) protein is a member of the multifunctional FET (FUS, EWS, and TAF15) family of proteins (1,2). These proteins are RNA and DNA binding proteins that are thought to be important for both transcriptional regulation and RNA processing. EWS can be found as part of a fusion protein with various E-twenty six (ETS) family transcription factors, most commonly Fli-1, in the Ewing sarcoma family of tumors (1-4). The amino terminus of the EWS protein, containing the transcriptional activation domain, is fused to the DNA binding domain of the ETS transcription factor, causing aberrant expression of target genes (1-5). EWS interacts with the transcription initiation complex via TFIID and RNA polymerase II subunits, as well as transcriptional regulators, such as Brn3A and CBP/p300, which suggests a role for EWS in transcriptional regulation (1,6-9). EWS also interacts with multiple components of the splicing machinery, implicating a role for EWS in RNA processing (1,10-12). EWS regulates the expression of cyclin D1, which controls G1-S phase transition during the cell cycle, at the level of transcriptional activation and mRNA splicing. The EWS-Fli-1 fusion protein has been shown to promote the expression of the cyclin D1b splice variant in Ewing sarcoma cells (13). In addition, EWS regulates the DNA damage-induced alternative splicing of genes involved in DNA repair and stress response and is required for cell viability upon DNA damage (14). Consistent with these results, EWS knockout mice display hypersensitivity to ionizing radiation and premature cellular senescence, suggesting a role for EWS in homologous recombination and maintenance of genomic stability (15).

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

Application Methods: Western Blotting

Background: Malate dehydrogenase (MDH) is a key enzyme in the tricarboxylic acid cycle and malate/aspartate shuttle (1,2). MDH is widely expressed in organisms from most bacteria to all eukaryotes (2). The cytoplasmic MDH isoenzyme (cMDH or MDH1) primarily reduces oxaloacetate to malate in the malate/aspartate shuttle (1-3). The major function of the mitochondrial MDH isoenzyme (mMDH or MDH2) is to oxidize malate to oxaloacetate in the tricarboxylic acid cycle (1,2).

$260
100 µl
APPLICATIONS
REACTIVITY
Bovine, Human, Monkey

Application Methods: Western Blotting

Background: PAI-1 is a secreted protein that belongs to the serine proteinase inhibitor (serpin) superfamily. It inhibits urokinase and tissue plasminogen activators (uPA and tPA) and thus, reduces the conversion of inactive plasminogen to plasmin (1). PAI-1 regulates fibrinolysis and plays an important role in vessel patency and tissue remodeling. Secreted PAI-1 interacts with the extracellular matrix (ECM) component vitronectin, thereby modulating cell-ECM interactions (2,3). PAI-1 is expressed in a variety of tissues with higher expression in liver, vascular endothelial cells, platelets, macrophages, and adipose tissue (1). Increased levels of PAI-1 are associated with deep vein thrombosis (4). Defects in PAI-1 cause plasminogen activator inhibitor-1 deficiency (PAI-1D), which is characterized by increased bleeding after injury or surgery (5). Research studies have shown that high levels of PAI-1 are associated with obesity, aging, insulin resistance, and type 2 diabetes (6-8). PAI-1 is transcriptionally regulated by TGF-β and mediates TGF-β-induced inhibition of cell migration and invasion in cancer cells (9). Studies have shown PAI-1 to be also involved in fibrosis (10).

$262
3 nmol
300 µl
SignalSilence® MDR1/ABCB1 siRNA II 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).

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

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

Background: Interferon regulatory factors (IRFs) comprise a family of transcription factors that function within the Jak/Stat pathway to regulate interferon (IFN) and IFN-inducible gene expression in response to viral infection (1). IRFs play an important role in pathogen defense, autoimmunity, lymphocyte development, cell growth, and susceptibility to transformation. The IRF family includes nine members: IRF-1, IRF-2, IRF-9/ISGF3γ, IRF-3, IRF-4 (Pip/LSIRF/ICSAT), IRF-5, IRF-6, IRF-7, and IRF-8/ICSBP. All IRF proteins share homology in their amino-terminal DNA-binding domains. IRF family members regulate transcription through interactions with proteins that share similar DNA-binding motifs, such as IFN-stimulated response elements (ISRE), IFN consensus sequences (ICS), and IFN regulatory elements (IRF-E) (2).

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

Application Methods: Western Blotting

Background: Wild-type p53 induced phosphatase 1 (WIP1)/protein phosphatase magnesium-dependent 1 delta (ppm1d) is a member of the PP2C family of serine/threonine protein phosphatases. WIP1 was initially identified as a p53 target gene, induced in response to ionizing radiation (1). Studies have shown that WIP1 is overexpressed in human cancers and is involved in the regulation of multiple DNA damage signaling pathways (reviewed in 2,3). WIP1 functions in returning cells to a homeostatic state following DNA damage (4,5), as well as in maintaining p53-dependent homeostasis under nonstress conditions (6). Researchers have shown that increased expression of WIP1 is associated with poor prognosis and lower survival rate in some human cancers (7,8). In contrast, overexpression of WIP1 in p53-negative tumor cells sensitizes them to chemotherapy-induced apoptosis while protecting normal tissue during treatment (9).

PhosphoPlus® Duets from Cell Signaling Technology (CST) provide a means to assess protein activation status. Each Duet contains an activation-state and total protein antibody to your target of interest. These antibodies have been selected from CST's product offering based upon superior performance in specified applications.

Background: Heat shock protein (HSP) 27 is one of the small HSPs that are constitutively expressed at different levels in various cell types and tissues. Like other small HSPs, HSP27 is regulated at both the transcriptional and posttranslational levels (1). In response to stress, the HSP27 expression increases several-fold to confer cellular resistance to the adverse environmental change. HSP27 is phosphorylated at Ser15, Ser78, and Ser82 by MAPKAPK-2 as a result of the activation of the p38 MAP kinase pathway (2,3). Phosphorylation of HSP27 causes a change in its tertiary structure, which shifts from large homotypic multimers to dimers and monomers (4). It has been shown that phosphorylation and increased concentration of HSP27 modulates actin polymerization and reorganization (5,6).

$314
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

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

Background: N-myc downstream-regulated gene 1 (NDRG1), also termed Cap43, Drg1, RTP/rit42, and Proxy-1, is a member of the NDRG family, which is composed of four members (NDRG1-4) that function in growth, differentiation, and cell survival (1-5). NDRG1 is ubiquitously expressed and highly responsive to a variety of stress signals including DNA damage (4), hypoxia (5), and elevated levels of nickel and calcium (2). Expression of NDRG1 is elevated in N-myc defective mice and is negatively regulated by N- and c-myc (1,6). During DNA damage, NDRG1 is induced in a p53-dependent fashion and is necessary for p53-mediated apoptosis (4,7). Research studies have shown that NDRG1 may also play a role in cancer progression by promoting differentiation, inhibiting growth, and modulating metastasis and angiogenesis (3,4,6,8,9). Nonsense mutation of the NDRG1 gene has been shown to cause hereditary motor and sensory neuropathy-Lom (HMSNL), which is supported by studies demonstrating the role of NDRG1 in maintaining myelin sheaths and axonal survival (10,11). NDRG1 is up-regulated during mast cell maturation and its deletion leads to attenuated allergic responses (12). Both NDRG1 and NDRG2 are substrates of SGK1, although the precise physiological role of SGK1-mediated phosphorylation is not known (13). NDRG1 is phosphorylated by SGK1 at Thr328, Ser330, Thr346, Thr356, and Thr366. Phosphorylation by SGK1 primes NDRG1 for phosphorylation by GSK-3.

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

Application Methods: Immunofluorescence (Immunocytochemistry), Western Blotting

Background: Protein ubiquitination and deubiquitination are reversible processes catalyzed by ubiquitinating enzymes (UBEs) and deubiquitinating enzymes (DUBs) (1,2). DUBs are categorized into 5 subfamilies: USP, UCH, OTU, MJD, and JAMM. UCHL1, UCHL3, UCHL5/UCH37, and BRCA-1-associated protein-1 (BAP1) belong to the ubiquitin carboxy-terminal hydrolase (UCH) family of DUBs, which all possess a conserved catalytic UCH domain of about 230 amino acids. UCHL5 and BAP1 have unique, extended carboxy-terminal tails. UCHL1 is abundantly expressed in neuronal tissues and testes, while UCHL3 expression is more widely distributed (3,4). Although UCHL1 and UCHL3 are the most closely related UCH family members with about 53% identity, their biochemical properties differ in that UCHL1 binds monoubiquitin and UCHL3 shows dual specificity toward both ubiquitin (Ub) and NEDD8, a Ub-like molecule.UCHL1 (PGP 9.5/PARK5) functions as a deubiquitinating enzyme and monoubiquitin stabilizer. In vitro studies have demonstrated that UCHL1 can hydrolyze isopeptide bonds between the carboxy-terminal glycine of Ub and the ε-amino group of lysine on target proteins. UCHL1 is also involved in the cotranslational processing of pro-ubiquitin and ribosomal proteins translated as ubiquitin fusions (5-7). Mice deficient in UCHL1 experience spasticity, suggesting that UCHL1 activity is required for the normal neuromuscular junction structure and function (5-7). Research studies have described loss of UCHL1 expression in numerous human malignancies, such as prostate, colorectal, renal, and breast carcinomas. Investigators have shown that loss of UCHL1 expression in breast carcinomas can be attributed to hyper-methylation of the UCHL1 gene promoter (8). While loss of UCHL1 expression is implicated in human carcinogenesis, mutation of UCHL1 has been implicated in neurodegenerative diseases such as Parkinson's and Alzheimer's (6,7).

$364
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 analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-HSP27 (Ser82) (D1H2F6) XP® Rabbit mAb #9709.
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Flow Cytometry

Background: Heat shock protein (HSP) 27 is one of the small HSPs that are constitutively expressed at different levels in various cell types and tissues. Like other small HSPs, HSP27 is regulated at both the transcriptional and posttranslational levels (1). In response to stress, the HSP27 expression increases several-fold to confer cellular resistance to the adverse environmental change. HSP27 is phosphorylated at Ser15, Ser78, and Ser82 by MAPKAPK-2 as a result of the activation of the p38 MAP kinase pathway (2,3). Phosphorylation of HSP27 causes a change in its tertiary structure, which shifts from large homotypic multimers to dimers and monomers (4). It has been shown that phosphorylation and increased concentration of HSP27 modulates actin polymerization and reorganization (5,6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: CHD8 belongs to the chromodomain helicase DNA-binding (CHD) family of ATP-dependent chromatin remodeling proteins (1). The CHD family of proteins has been shown to play an important role in regulating gene expression by utilizing the energy derived from ATP hydrolysis to alter chromatin architecture (1,2). The nine CHD family members are characterized by the presence of two tandem chromodomains in the N-terminal region and an SNF2-like ATPase domain near the central region of the protein (2-4). In addition, CHD8 contains three CR (conserved region) domains, a SANT (switching-defective protein 3, adaptor 2, nuclear receptor co-repressor, transcription factor IIB)-like domain, two BRK (brahma and kismet) domains, and a DNA-binding domain (2). The chromatin remodeling activity of CHD8 has been shown to be important for the regulation of a wide variety of genes, such as the HOX genes (5) and genes that are driven by β-catenin (6), p53 (7), estrogen receptor (8), or androgen receptor (9). CHD8 can also interact with the insulator binding protein CTCF and is required for CTCF insulator activity at multiple gene loci (10).

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

Application Methods: Western Blotting

Background: The extracellular matrix (ECM) is a complex structure of secreted macromolecules surrounding mammalian organs and tissues. Controlled interactions between cells and the ECM are important in proliferation, migration, survival, polarity, and differentiation. Cells contact the ECM primarily through focal adhesion complexes, which contain integrins, as well as multiple adaptor and signaling proteins (1). The ILK/PINCH/Parvin (IPP) adaptor complex acts at the interface of the integrin/actin connection to regulate formation of focal adhesions and integrin signaling. Roles for IPP proteins outside of the IPP complex have been proposed, including regulation of gene expression (2,3).PINCH, also known as LIMS1, has been shown to function as a specific regulator of gene expression in glomerular podocytes in response to TGF-β1 (4). Researchers have shown that PINCH is highly expressed in some human tumors, and that PINCH can promote resistance to ionizing radiation through activation of Akt (5,6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: Phosphoinositide 3-kinase (PI3K) catalyzes the production of phosphatidylinositol-3,4,5-triphosphate by phosphorylating phosphatidylinositol (PI), phosphatidylinositol-4-phosphate (PIP), and phosphatidylinositol-4,5-bisphosphate (PIP2). Growth factors and hormones trigger this phosphorylation event, which in turn coordinates cell growth, cell cycle entry, cell migration, and cell survival (1). PTEN reverses this process, and research studies have shown that the PI3K signaling pathway is constitutively activated in human cancers that have loss of function of PTEN (2). PI3Ks are composed of a catalytic subunit (p110) and a regulatory subunit. Various isoforms of the catalytic subunit (p110α, p110β, p110γ, and p110δ) have been isolated, and the regulatory subunits that associate with p110α, p110β, and p110δ are p85α and p85β (3). In contrast, p110γ associates with a p101 regulatory subunit that is unrelated to p85. Furthermore, p110γ is activated by βγ subunits of heterotrimeric G proteins (4).

PhosphoPlus® Duets from Cell Signaling Technology (CST) provide a means to assess protein activation status. Each Duet contains an activation-state and total protein antibody to your target of interest. These antibodies have been selected from CST's product offering based upon superior performance in specified applications.

Background: 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).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

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

The Resazurin Cell Viability Kit is a fluorescent assay that detects cellular metabolic activity. The blue nonfluorescent resazurin reagent is reduced to highly fluorescent resorufin by dehydrogenase enzymes in metabolically active cells. This conversion only occurs in viable cells and thus, the amount of resorufin produced is proportional to the number of viable cells in the sample. The resorufin formed in the assay can be quantified by measuring the relative fluorescence units (RFU) using a fluorometer (Ex=530-570 nm, Em=590-620 nm).
$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 and immunofluorescent analysis in human cells. This antibody is expected to exhibit the same species cross-reactivity as the unconjugated Ki-67 (D3B5) Rabbit mAb #9129.
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

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

Background: Ki-67, named after the location where it was discovered (Kiel University, Germany), is a nuclear nonhistone protein (1) that is universally expressed among proliferating cells and absent in quiescent cells (2). Ki-67 detects proliferating cells in G1, S, G2, and mitosis, but not in the G0 resting phase. Research studies have shown that high levels of Ki-67 are associated with poorer breast cancer survival (3). Research studies have explored the use of Ki-67, along with other markers, as potential prognostic or predictive markers in breast cancer and other malignant diseases (4).

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

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

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome and their activities are regulated via the sequential binding of pre-replication and replication factors. The origin recognition complex (ORC) is thought to bind to chromatin throughout the cell cycle (1,2). The pre-replication complex (Pre-RC) forms in late mitosis/early G1 phase with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase and formation of the Pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases cdk2 and cdc7. Cdc7 phosphorylates MCM proteins bound to chromatin and, in conjunction with CDT1, recruits the replication factor cdc45 (3-5). Cdc45 is required for formation of pre-initiation complexes at the G1/S transition and for activation of replication origins. The level of cdc45 protein expression is associated with the proliferative status of the cell or tissue. Terminally differentiated and senescent cells lack cdc45 and highly proliferative cell lines express high levels of cdc45 (6).

$364
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-HS1 (Tyr397) (D12C1) XP® Rabbit mAb #8714.
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry

Background: HS1 (HCLS1, LckBP1, p75) is a protein kinase substrate that is expressed only in tissues and cells of hematopoietic origin (1,2). HS1 contains four cortactin repeats and a single SH3 domain (2). This intracellular protein is phosphorylated following immune receptor activation, which promotes recruitment of HS1 to the immune synapse (3-5). Phosphorylation of HS1 is required to regulate actin dynamics and provide docking sites for many other signaling molecules, such as Vav1 and PLCγ1 (6). HS1 also plays an important role in platelet activation (7).

$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, Monkey, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: Protein ubiquitination requires the concerted action of the E1, E2, and E3 ubiquitin-conjugating enzymes. Ubiquitin is first activated through ATP-dependent formation of a thiol ester with ubiquitin-activating enzyme E1. The activated ubiquitin is then transferred to a thiol group of ubiquitin-carrier enzyme E2. The final step is the transfer of ubiquitin from E2 to an ε-amino group of the target protein lysine residue, which is mediated by ubiquitin-ligase enzyme E3 (1).

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

Application Methods: Western Blotting

Background: Upf1 was identified as an active component in nonsense-mediated decay (NMD), an mRNA surveillance mechanism in eukaryotic cells that degrades mRNAs containing premature termination codons (1). Upf1 was found to be an ATP-dependent RNA helicase in the cytoplasm (2) and was later shown to be a component of cytoplasmic P-bodies (3). Upf1 phosphorylation mediates the repression of translation that accompanies NMD, allowing mRNA accessibility to the NMD machinery (4). Two other active components of NMD, Upf2 and Upf3, were also identified and described as having perinuclear and nucleocytoplasmic localization, respectively (5).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: G protein-coupled receptor (GPCR) kinase interacting proteins 1 and 2 (GIT1 and GIT2) are highly conserved, ubiquitous scaffold proteins involved in localized signaling to help regulate focal contact assembly and cytoskeletal dynamics. GIT proteins contain multiple interaction domains that allow interaction with small GTPases (including ARF, Rac, and cdc42), kinases (such as PAK and MEK), the Rho family GEF Pix, and the focal adhesion protein paxillin (reviewed in 1). GIT1 and GIT2 share many of the same properties, but with at least ten distinct, tissue-specific splice variants. GIT2 has been shown to play an important role inhibiting focal adhesion turnover and membrane protrusion (2,3). Focal adhesion localization and paxillin binding of GIT2 is regulated through phosphorylation at one or more tyrosine sites (Tyr286, Tyr392, Tyr592) by FAK and/or Src (4,5,reviewed in 6). Once at the focal adhesion, GIT2 is thought to play a key role in cell polarity and migration, making it a protein of interest in the investigation of oncogenic signaling pathways (3,5,7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse

Application Methods: Immunoprecipitation, Western Blotting

Background: NBC1/SLC4A4 is an eletrogenic sodium bicarbonate cotransporter. It mediates the coupled movement of Na+ and HCO3- ions across the basolateral membrane of cells. NBC1 regulates secretion and absorption of bicarbonate and modulates intracellular pH (1-3). There are five isoforms of NBC1 produced by alternative splicing including the most studied isoforms, 1 and 2, which have different N termini. The N terminus of isoform 1 contains multiple consensus phosphorylation sites for various kinases, such as PKA, PKC, and CK II, and may play a regulatory role in the biological function of NBC1 (4). Interaction with carbonic anhydrase II, IV, and IX regulates the transporter acitivity of NBC1 (5-7). NBC1 is expressed in various tissues with the exception of isoform 2, which is mainly expressed in kidney proximal tubules (1). Isoform 1 is expressed in the pancreas and corneal endothelium, and at low levels in other tissues including heart, skeletal muscle, liver, and prostate (4). Research studies have shown that mutations in the NBC1 gene are linked to proximal renal tubular acidosis with ocular abnormalities (also known as renal tubular acidosis II).

$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 monkey cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated Phospho-Bad (Ser112) (40A9) Rabbit mAb #5284.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry

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, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The 20S proteasome is the major proteolytic enzyme complex involved in intracellular protein degradation. It consists of four stacked rings, each with seven distinct subunits. The two outer layers are identical rings composed of α subunits (called PSMAs), and the two inner layers are identical rings composed of β subunits. While the catalytic sites are located on the β rings (1-3), the α subunits are important for assembly and as binding sites for regulatory proteins (4). Seven different α and ten different β proteasome genes have been identified in mammals (5). PA700, PA28, and PA200 are three major protein complexes that function as activators of the 20S proteasome. PA700 binds polyubiquitin with high affinity and associates with the 20S proteasome to form the 26S proteasome, which preferentially degrades poly-ubiquitinated proteins (1-3). The proteasome has a broad substrate spectrum that includes cell cycle regulators, signaling molecules, tumor suppressors, and transcription factors. By controlling the degradation of these intracellular proteins, the proteasome functions in cell cycle regulation, cancer development, immune responses, protein folding, and disease progression (6-9).