| Description | Caveolin-1 (82-101) amide (human, mouse, rat) (Caveolin-1 scaffolding domain peptide) is a peptide that reverses aging-associated deleterious changes in multiple organs. Caveolin-1 (82-101) amide (human, mouse, rat) inhibits tyrosine kinases | Protein Purity>95% by SDS-PAGEExtinction Coeff.A276 nm = 0.456 at 1.0 mg/mLMolecular Weight8,759 Da (single chain)General DescriptionNatural human C4a is prepared by cleavage of human C4 protein by human C1s. It is produced during activation of both the classical and lectin pathways of complementProtein Purity>95% by SDS-PAGEExtinction Coeff.A276 nm = 0.456 at 1.0 mg/mLMolecular Weight8,759 Da (single chain)General DescriptionNatural human C4a is prepared by cleavage of human C4 protein by human C1s. It is produced during activation of both the classical and lectin pathways of complement. C4a is a member of the anaphylatoxin family of three proteins (C3a, C4a and C5a) produced by the activation of complement (Hugli, T.E. et al. (1981)). It is an unglycosylated polypeptidecontaining 77 amino acids with a molecular mass of 8,759 daltons. Many of the biological functions of C4a are similar to those of C3a, but the specific activities are far below those of C3a. C4a activity is so low, in fact, that it was initially thought to be inactive. These measured activities include inducing muscle contraction in the guinea pig ileum test (spasmogenic activity), desensitization of muscle to C3a stimulation suggesting that the same receptor for both C3a and C4a is involved (tachyphylactic activity) and inducing vascular permeability in human skin (Gorski J.P. et al. (1979)). C4a does not show tachyphylactic activity against C5a or chemotactic activity. Removal of the C-terminal arginine by serum carboxypeptidase N destroys all these activities (Meuller-Ortiz, S.L., et al. (2009)). C4a appears to act through the C3a receptor (C3aR) which is a G-protein coupled receptor found widely distributed on peripheral tissues, lymphoid cells (neutrohphils, monocyes, and eosinophils) and in the central nervous system (astrocytes, neurons and glial cells) (Law, S.K.A. and Reid, K.B.M. (1995)). Physical Characteristics & StructureMolecular weight: 8,759 calculated molecular mass. Observed mass (MALDI-TOF) is 8,762 + 9 mass units. pI = 9.0 to 9.5 (Gorski, J.P. et al. (1981))Amino acid sequence (77 amino acids): NVNFQKAINE KLGQYASPTA KRCCQDGVTR LPMMRSCEQR AARVQQPDCR EPFLSCCQFA ESLRKKSRDK GQAGLQRC4a is thought to be structurally very similar to C3a and C5a to which it is homologous. Thus its 3D structure is probably similar to the X-ray-derived crystal structureof C3a (Huber, R. et al. (1980)) and the NMR derived structure of C3a: Nettesheim, D.G. et al. (1988); Murray, I. et al. (1999).FunctionSee General Description above. C4a exhibits much weaker biological activities than C3a and C5a. Its activity in inducing erythema and edema in human skin is 25,000-fold weaker than that of C5a and 100-fold weaker than C3a per nanomole. The spasmogenic activity of C4a is 2000-fold weaker than C5a and 100-fold weaker than that of C3a. Due to these differences the role of C4a in these responses in vivo is thought to be negligible.AssaysTwo well established assays for C4a and C3a functional activities include induction of contraction in the guinea pig ileum and the permeation of a dye such as trypan blue from the vasculature into skin. The anaphylatoxins also induce mast cell degranulation, (measured as histamine release), platelet aggregation, IL-1 release from monocytes and the release of prostaglandins and leukotrienes from many cells and tissues. The other assays used for C3a (Dodds, A.W. and Sim, R.B. (1997)) should also respond to C4a, but few reports have described utilizing these assays with C4a. ELISA kits for the assay of C4a levels (or more correctly C4a desArg levels) in blood and other fluids are sold by several companies. These measurements are useful for detecting complement activation in vivo, but the interpretation of their meaning is complicated by the fact that clearance of the anaphylatoxins is rapid. In vivoFreshly drawn normal human serum contains significant levels of all three anaphylatoxins. Although these may represent the resting concentration in vivo it is difficult to draw or store blood without some complement activation so a true in vivo concentration is difficult to determine. The presence of EDTA and Futhan in the collection tubes can minimize this background (Pfeifer, P.H. et al. (1999)). Full activation of all C4 in blood (600µg/mL) would result in ~3,400 nM C4a (~30 µg/mL). Due to the low biological activity of C4a it could require activation of most of the C4 in a small region to achieve the micromolar C4a concentrations necessary to elicit a response.RegulationC4a levels are regulated by three processes: formation, inactivation and clearance. There are two enzymes that cleave C4 and release C4a: C1s and MASP-2. C4a is “inactivated” by removal of its C-terminal arginine amino acid. The product C4a desArg (or C4a without the C-terminal arginine) is produced by the action of the plasma enzyme carboxypeptidase N (Mueller-Ortiz S.L. et al. (2009)). The inactivation is rapid and most C4a is converted to C4a desArg within minutes of its formation. Inactivated C4a lack measurable biological activity. Because of the large number of cells bearing C3a/C4areceptors (endothelial, immune, smooth muscle, neuronal, etc.) the capture, internalization and digestion of C4a and C4a desArg probably results in its removal from circulation.DeficienciesA deficiency of C4 or a deficiency of all of the enzymes that cleave C4 to generate C4a could result in the absence of C4a. There are no known complete deficiencies of all ofthe C4 cleaving enzymes. Examples of C4 deficient humans and mice exist (Wessels, M.R. et al. (1995)), but the degree to which pathologies associated with C4 deficiency are due to the lack of C4 or the absence of C4a is unclear. DiseasesThere are no known diseases connected to C4a or C4a desArg. Precautions/Toxicity/HazardsThe source of C4a is human serum, therefore appropriate precautions must be observed even though the source was shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II.Injection can cause anaphylatic shock which is a generalized circulatory collapse similar to that caused by an allergic reaction.Hazard Code: B WGK Germany 3... Read More | Bovine pancreatic deoxyribonuclease is an endonuclease which splits phosphodiester linkages, preferentially adjacent to a pyrimidine nucleotide yielding polynucleotides with free hydroxyl group at the 3' position and phosphate group at the 5' position. The average chain length of a limit digest is aBovine pancreatic deoxyribonuclease is an endonuclease which splits phosphodiester linkages, preferentially adjacent to a pyrimidine nucleotide yielding polynucleotides with free hydroxyl group at the 3' position and phosphate group at the 5' position. The average chain length of a limit digest is a tetranucleotide.Used for the removal of DNA from protein samples. Deoxyribonuclease I from bovine pancreas has been used in a study to compare several procedures for reducing RNase contamination in preparations of DNase. Deoxyribonuclease I from bovine pancreas has also been used in a study to investigate the effect of the composition of sodium dodecyl sulfate preparations on the renaturation of enzymes after polyacrylamide gel electrophoresis... Read More | GoldStar Probe Mixture is a premixed system specifically designed for real-time fluorescence quantitative PCR using probe methods (TaqMan, Molecular Beacon, etc.), with a concentration of 2 x, containing GoldStar Taq DNA Polymerase, PCR Buffer, dNTPs, and Mg2+. The operation is simple and convenientGoldStar Probe Mixture is a premixed system specifically designed for real-time fluorescence quantitative PCR using probe methods (TaqMan, Molecular Beacon, etc.), with a concentration of 2 x, containing GoldStar Taq DNA Polymerase, PCR Buffer, dNTPs, and Mg2+. The operation is simple and convenient. Mainly used for detecting genomic DNA target sequences and RNA reverse transcription cDNA target sequences, such as gene expression analysis, copy number analysis, SNP genotype analysis, etc., suitable for fluorescence quantification using different types of probe methods. The GoldStar Taq DNA Polymerase contained in this product is a chemically modified, novel and highly efficient hot start enzyme. It has no polymerase activity at room temperature, effectively avoiding non-specific amplification caused by non-specific binding of primers and templates or primer dimerization at room temperature. The enzyme activation requires incubation at 95 ℃ for 10 minutes. The unique combination of PCR buffer system and hot start enzyme significantly improves the amplification efficiency of PCR, with stronger fluorescence signal and higher sensitivity, which can detect single copy templates. By using this product, a wider linear range can be obtained, resulting in more accurate quantification of the target gene. Suitable for all fluorescence quantitative PCR instruments that do not require ROX as a calibration dye.ROX dye is used to correct the fluorescence signal error between wells in quantitative PCR instruments, and is generally used in Real Time PCR amplification instruments from companies such as ABI and Stratagene. The excitation optical systems of different instruments vary, so the concentration of ROX dye must be matched with the corresponding fluorescence quantitative PCR instrument.Instruments that do not require ROX calibration (CW0932): Roche LightCycle 480, Roche LightCyler 96, Bio rad iCyler iQ, iQ5, CFX96, etc.Instrument requiring Low ROX calibration (CW2625): ABI Prism7500/7500 Fast, QuantStudio ® 3 System, QuantStudio ® 5 System, QuantStudio ® 6 Flex System, QuantStudio ® 7 Flex System, ViiA 7 System, Stratagene Mx3000/Mx3005P, Corbett Rotor Gene 3000, etc.Instruments that require High ROX calibration (CW2626): ABI Prism7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, etc.G665832Component5 mLStorageG665832A2×GoldStar Probe Mixture5×1 mL-20℃. Avoid freeze/thaw cycle.G665832BddH2O5×1 mL -20℃. Avoid freeze/thaw cycle. Notes:1. Before use, please gently mix upside down to avoid foaming, and use after briefly centrifugation.2. Avoid repeated freezing and thawing of this product, as repeated freezing and thawing may cause a decrease in product performance. This product can be stored for a long time at -20 ℃, away from light. If frequent use is required in the short term, it can be stored at 2-8 ℃.Usage:The following are examples of conventional PCR reaction systems and reaction conditions. In practical operation, corresponding improvements and optimizations should be made based on different templates, primer structures, and target fragment sizes.1. PCR reaction system Reagent 50 µl Reaction system Final concentration 2×GoldStar Probe Mixture 25 µl 1 × Forward Primer，10 µM 1 µl 0.2 µM¹⁾ Reverse Primer，10 µM 1 µl 0.2 µM¹⁾ Probe，10 µM 1 µl 0.2 µM²⁾ Template DNA 2 µl³⁾ / 50×Low ROX or High ROX（optional）⁴⁾ 1 µl 1 × ddH2O up to 50 µl / Attention:1) Typically, the primer concentration is 0.2 µ M can achieve good results, ranging from 0.1 to 1.0 µ M serves as a reference for setting the range.2) The concentration of the probe used is related to the fluorescent quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance. Please refer to the instrument manual or the specific usage requirements of each fluorescent probe for concentration adjustment during actual use.3) The amount of DNA template is usually based on 10-100 ng genomic DNA or 1-10 ng cDNA as a reference. Due to the different copy numbers of target genes contained in templates of different species, gradient dilution can be applied to the template to determine the optimal template usage.4) The excitation optical systems of different instruments vary, and depending on the instrument used for fluorescence quantification, 50 x Low ROX or 50 x High ROX can be added.2. PCR reaction programAttention! The pre denaturation reaction of this product must be completed at 95 ℃ for 10 minutes!Two step PCR Step Temperature Time / Pre denaturation 95℃ 10 min¹⁾ / Denaturation 95℃ 15 s 35-40 cycles Annealing/Extension ²⁾ 60℃ 1 min 35-40 cycles Attention:1) The hot start enzyme used in this product must be activated under pre denaturation conditions of 95 ℃ and 10 minutes.2) It is recommended to use a two-step PCR reaction program. If good experimental results cannot be obtained due to the use of primers with lower Tm values, a three-step PCR amplification can be attempted. The annealing temperature should be set within the range of 56 ℃ -64 ℃ as a reference... Read More | Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed Reverse transcriptases are enzymes encoded in retroviruses viral genome. The enzyme is responsible for transcription of the viral RNA to produce a dsDNA that can be inserted into the host genome.Reverse transcriptases are multifunctional enzymes. These enzymes exhibit an RNA and DNA directed polymerase activity. In addition reverse transcriptases catalyze the degradation of RNA in an RNA-DNA hybrid. The exonucleolytic activity proceeds in a 5' ---> 3' direction. The RNA or DNA directed activity requires a template (RNA or DNA) and a primer. The following is a schematic illustration of the reaction:Unit definition: One unit incorporates 1 nanomole of tritiated dTMP into acid insoluble productsusing poly(A)•oligo(dT) 12-18 as the template-primer in 20 minutes at 37° C.ApplicationsHIV reverse transcriptase is used for research on the AIDS primer. However it can be substituted for AMV reverse transcriptase, which is mainly used to transcribe mRNA into double stranded cDNA, that can be inserted into prokaryotic vectors. The enzyme can also be used with either single stranded DNA or RNA templates to make probes for use in hybridization experiments. It can be used for labeling the termini of DNA fragments with protruding 5' termini. The enzyme can also be used to sequence DNAs by the dideoxy chain termination method of Sanger when the Klenow fragment of E. coli DNA polymerase I, or the T7 DNA polymerase yield unsatisfactory results.Reagents0.05 M Tris, pH 8.3, containing 0.008 M MgCl21 mg/ml polyadenylic acid in water (poly A)DNA primer:Oligo d(T)12-181 µ mole dTTP/mL stock solution[methyl-3H]-Thymidine 5'-triphosphate (3H-dTTP)dTTP-3H-dTTP working mix: Add 1-2 µL 3H-dTTP per mL of 100 nmol/mL dTTP in order to obtain 1 to 1.5 x 105 cpm/mL1% bovine serum albumin10% perchloric acid1% perchloric acidBuffer substrate reaction mixture: Prepare fresh, immediately before use:For each 1mL of reaction mixture required mix:0.7 mL Tris/HCl, pH 8.3, 0.008M MgCl20.3 mL 1 mg/mL poly(A) RNA template0.005 mL 0.02 mg/mL oligo d(T)12-18 DNA primer0.02mL 1% BSAEnzymedilute as needed wtih 0.05M Tris/HCl, pH 8.3, 0.008M MgCl2 containing 0.1 mg/mL (1%) BSAProcedurePipette into each tube as follows:Buffer substrate mix：0.1 mLdTTP-3H3-dTTP：0.1 mLEnzyme：5-10 µLIncubate 20 minutes at 37° C. Stop reaction by adding 1 ml 10% cold perchloric acid. Filter through 0.2µ manifold filters used with Millipore vacuum manifold. Wash four times using 2mL 1% cold perchloric acid/wash. Transfer filter to scintillation vials. Add 2mL Cellosolve (or 2-methoxyethanol) to dissolve filter. Filters become opaque upon addition of Cellosolve. Make sure filters are dissolved before proceeding. Add 10mL scintillation cocktail and count.Calculation... Read More |