This peptide can be used to block Zap-70 (99F2) Rabbit mAb #2705.
Background: The Syk family protein tyrosine kinase Zap-70 is expressed in T and NK cells and plays a critical role in mediating T cell activation in response to T cell receptor (TCR) engagement (1). Following TCR engagement, Zap-70 is rapidly phosphorylated on several tyrosine residues through autophosphorylation and transphosphorylation by the Src family tyrosine kinase Lck (2-6). Tyrosine phosphorylation correlates with increased Zap-70 kinase activity and downstream signaling events. Expression of Zap-70 is correlated with disease progression and survival in patients with chronic lymphocytic leukemia (7,8).
This peptide is used to block 4E-BP1 (53H11) Rabbit mAb #9644 reactivity in western blot and dot blot protocols.
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).
This peptide is used to specifically block β-Actin (13E5) Rabbit mAb #4970 by dot blot.
Background: Actin, a ubiquitous eukaryotic protein, is the major component of the cytoskeleton. At least six isoforms are known in mammals. Nonmuscle β- and γ-actin, also known as cytoplasmic actin, are predominantly expressed in nonmuscle cells, controlling cell structure and motility (1). α-cardiac and α-skeletal actin are expressed in striated cardiac and skeletal muscles, respectively; two smooth muscle actins, α- and γ-actin, are found primarily in vascular smooth muscle and enteric smooth muscle, respectively. These actin isoforms regulate the contractile potential of muscle cells (1). Actin exists mainly as a fibrous polymer, F-actin. In response to cytoskeletal reorganizing signals during processes such as cytokinesis, endocytosis, or stress, cofilin promotes fragmentation and depolymerization of F-actin, resulting in an increase in the monomeric globular form, G-actin (2). The ARP2/3 complex stabilizes F-actin fragments and promotes formation of new actin filaments (2). Research studies have shown that actin is hyperphosphorylated in primary breast tumors (3). Cleavage of actin under apoptotic conditions has been observed in vitro and in cardiac and skeletal muscle, as shown in research studies (4-6). Actin cleavage by caspase-3 may accelerate ubiquitin/proteasome-dependent muscle proteolysis (6).
This peptide is used to block β-Catenin (6B3) Rabbit mAb #9582 and β-Catenin Antibody (Carboxy-terminal Antigen) #9587 reactivity in dot blot protocols.
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).
This peptide is used to block β-Tubulin (9F3) Rabbit mAb #2128 reactivity.
Background: The cytoskeleton consists of three types of cytosolic fibers: microtubules, microfilaments (actin filaments), and intermediate filaments. Globular tubulin subunits comprise the microtubule building block, with α/β-tubulin heterodimers forming the tubulin subunit common to all eukaryotic cells. γ-tubulin is required to nucleate polymerization of tubulin subunits to form microtubule polymers. Many cell movements are mediated by microtubule action, including the beating of cilia and flagella, cytoplasmic transport of membrane vesicles, chromosome alignment during meiosis/mitosis, and nerve-cell axon migration. These movements result from competitive microtubule polymerization and depolymerization or through the actions of microtubule motor proteins (1).
EDTA (Ethylenediaminetetraacetic acid) is a common laboratory chelating agent of divalent cations, such as Ca2+ and Mg2+. Ultrapure 0.5 M EDTA, pH 8.0 from Cell Signaling Technology contains no detectable DNase, RNase, or protease activity. The convenient 1 ml vials reduce the likelihood of contamination that can occur with larger volume containers. It is suitable for use in molecular biology or protein biochemistry applications that require the chelation of divalent metal cations.This product is used in our SimpleChip® chromatin immunoprecipitation (ChIP) assays to stop the metal-dependant enzymatic digestion of cross-linked DNA by micrococcal nuclease once the reaction is complete. It can be added to cell lysis buffers for use as a metalloprotease inhibitor. Working concentrations are typically 1-5 mM in this application.
Premium 16% (w/v) Formaldehyde from Cell Signaling Technology is used as a fixative agent for fluorescent immunocytochemical and flow cytometry assays. It is methanol-free, prepared from high quality paraformaldehyde, and packaged under an inert atmosphere of nitrogen.Each 10 ml solution is supplied in an amber glass vial with two access points, offering distinct advantages over pre-scored ampules. The screw cap allows for easy access to large volumes if necessary. To extend the product's shelf life, small volumes should be extracted by piercing the silicone top with a needle and syringe.
4% (w/v) Formaldehyde from Cell Signaling Technology is a ready-to-use fixative agent for fluorescent immunocytochemical and flow cytometry assays. It is formulated in 1X PBS, methanol-free, prepared from high-quality paraformaldehyde, and packaged under an inert atmosphere of nitrogen.
Ammonium bicarbonate buffer is supplied as a one molar (1M) concentrated stock in HPLC grade water. This buffer is recommended for use in PTMScan protocols for LC-MS applications during the digestion procedures.
Animal-Free Blocking Solution (5X) is designed for use as a blocking reagent in chromogenic immunohistochemical assays (IHC) and western blotting. This plant-based product contains no animal-derived proteins and can be used to decrease background in place of normal goat serum, BSA, or non-fat dry milk.
BackDrop® Green Background Suppressor is a novel reagent designed to effectively suppress green background fluorescence and improve live cell image quality, eliminating the need for medium removal and potential cell loss. BackDrop® Green is supplied as a ready-to-use liquid in a convenient dropper bottle and is applied directly to live cell imaging samples.
Ultra pure bovine serum albumin (BSA) is used as a blocking agent during Western blotting to reduce background and non-specific binding. BSA can also be used in other protocols that involve antibody binding including ELISA, DELFIA, flow cytometry and immunofluorescence/immunocytochemistry.
Dithiothreitol (DTT) from Cell Signaling Technology is offered in a convenient 192.8 mg lyophilized format, allowing for preparation of a fresh stock solution. This DTT reagent contains no detectable DNase or RNase activity and is suitable for use in molecular biology or protein biochemistry applications that require reduction of protein disulfide bonds.SDS-PAGE sample buffers are routinely supplemented with 10-50 mM DTT to cleave protein disulfide bonds. Lower concentrations of DTT are routinely used to stabilize enzymes or other proteins that posses free sulfhydryl groups, which is useful in chromatin immunoprecipitation (ChIP) assays.
FastScan™ ELISA Cell Extraction Enhancer Solution (50X) is used with FastScan™ ELISA Cell Extraction Buffer (5X) #69905 (not supplied) to prepare and dilute cell extracts for use in FastScan™ ELISA Kits.
Alexa Fluor® and many other anionic fluorescent dyes and proteins can bind nonspecifically with cationic cell and tissue constituents. By efficiently blocking these nonspecific electrostatic interactions, Image-iT® FX Signal Enhancer can dramatically improve the signal-to-noise ratio of immunolabeled cells and tissues. Image-iT® is a liquid that is applied directly to slides or coverslips containing fixed and permeabilized cell or tissue samples prior to staining with fluorescent probes.
Micrococcal nuclease is a relatively non-specific endo-exonuclease derived from Staphylococcus aureus. Active in the pH range of 7.0-10.0, this product digests double-stranded, single-stranded, circular, and linear nucleic acids.In the SimpleChIP® Enzymatic Chromatin IP kit assay, following cell lysis, the chromatin is fragmented by partial digestion with micrococcal nuclease to obtain chromatin fragments of 1 to 5 nucleosomes in size. Enzymatic digestion of chromatin is much milder than sonication and eliminates problems due to variability in sonication power and emulsification of chromatin during sonication, which can result in incomplete fragmentation of chromatin or loss of antibody epitopes due to protein denaturation and degradation.This product is offered to conveniently provide additional micrococcal nuclease when fragmenting chromatin with our SimpleChIP® (#9002, #9003) and SimpleChIP® Plus (#9004, #9005) Enzymatic Chromatin IP Kits. These kits provide all the reagents required for performing 6 chromatin preparations (or optimizations) and 30 chromatin immunoprecipitation (ChIP) assays, however there are instances where extra micrococcal nuclease is desired.
Premium quality normal goat serum for use as blocking reagent and antibody diluent for chromogenic and fluorescent immunohistochemical and immunocytochemical assays. Typically, normal serum from the same species as the secondary antibody is used in the blocking and diluent buffers.
Ultrapure Nuclease-free Water from Cell Signaling Technology is non-DEPC treated, endotoxin-tested, and contains no detectable endo- and exo-nucleases. Following stringent purification, it is 0.1 µm filtered into a polycarbonate bottle and autoclaved. It is suitable for molecular biology applications that require water devoid of nucleases.
This Phosphatase Inhibitor Cocktail is used to prevent dephosphorylation of phosphorylated proteins from active serine/threonine and tyrosine phosphatases present in whole cell extract. The 100X cocktail is a colorless to light yellow liquid.
Phenylmethanesulfonyl Fluoride (PMSF) is an inhibitor of serine proteases such as trypsin, chymotrypsin, thrombin, and papain. It is routinely added as a supplement to lysis buffers just prior to lysis, to prevent protease degradation. Cell Signaling Technology recommends adding PMSF at 1 mM to Cell Lysis Buffer (#9803) and RIPA Buffer (#9806). Molecular Formula: C7H7FO2S Molecular Weight: 174.19 CAS: 329-98-6
Ponceau S Staining Solution is supplied as ready to use. This product is recommended for rapid and reversible protein staining on nitrocellulose or PVDF membranes. This staining technique is often utilized to confirm protein electrotransfer in Western blotting assays prior to antibody-based detection.
When diluted in lysis buffer to a final concentration of 1X the Protease Inhibitor Cocktail prevents protein degradation by endogenous proteases present in whole cell extract. The 100XProtease Inhibitor Cocktail is a clear, colorless liquid.
When diluted in lysis buffer to a final concentration of 1X the Protease/Phosphatase Inhibitor Cocktail prevents protein degradation and dephosphorylation by endogenous proteases and phosphatases present in the whole cell extract. The 100X cocktail is a clear light yellow to light green liquid.
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).