| Description | APOA2 Human Pre-designed siRNA Set A contains three designed siRNAs for APOA2 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components APOA2 siRNA-1: 5 nmol (HPLC) APOA2 siRNA-2: 5 nmol (HPLC) APOA2 siRNA-3: 5 nmol (HPLC) siRNA Negative Control:APOA2 Human Pre-designed siRNA Set A contains three designed siRNAs for APOA2 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components APOA2 siRNA-1: 5 nmol (HPLC) APOA2 siRNA-2: 5 nmol (HPLC) APOA2 siRNA-3: 5 nmol (HPLC) siRNA Negative Control: 5 nmol (HPLC) FAM-labeled siRNA Negative Control: 5 nmol (HPLC) GAPDH siRNA Positive Control:5 nmol (HPLC)... Read More | Inquire | C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and the other prefer 40% glycerol in the storage buffer.C1q is purified from pooled normal human plasma. C1q is part of the C1 complex and this complex is the first complement component in the cascade referred to as the classical pathway of complement. C1 is actually a non-covalent assembly of three different proteins (C1q, C1r, and C1s) bound together in a calcium-dependent complex. C1q has six extended arms with domains at the end of each arm that bind to the Fc domains of immunoglobulins. When antibodies bind to antigens forming immune complexes they cluster allowing two or more of its six arms of C1q to bind to the Fc domains of antibodies such as IgG or IgM. The binding of multiple arms to immune complexes causes the two C1r proteins in the complex (protease zymogens) to auto-activate producing two C1r proteases that cleave and activate the two C1s protease zymogens in the complex. Activated C1s cleaves complement component C4 releasing C4a and initiating covalent attachment of C4b to the activating surface. Activated C1s also cleaves C2 and the larger fragment of C2 binds to the surface-attached C4b forming C4b,C2a which is the C3/C5 convertase of the classical pathway.Extinction Coeff.A₂₈₀ nm = 0.68 at 1.0 mg/ml for pure C1q Molecular weight:410,000 Da (18 chains)Preservative:None, 0.22 µm filtered.Source:Normal human serum (shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II).Physical Characteristics & StructureC1q is a high molecular weight complex of 18 polypeptide chains. Each of the six arms of C1q contains three chains, an A chain (26,000 daltons), a B chain (25,000 daltons) and a C chain (24,000 daltons). The three chains are coiled into a collagen-like triple helix over approximately half their length. Half of this collagen region forms a central core where all 18 chains come together. The chains are joined in this core by disulfides in the pattern A-B and C-C. There is a bend in the center of the collagen region allowing the arms to extend away from each other. Globular heads at the far ends of the collagen arms possess binding sites for Fc domains of immunoglobulins. C1 complex is composed of one C1q molecule (410,000 daltons), two C1r molecules (92,000 daltons) and two C1s molecules (86,000 daltons). The complex is stable in the presence of calcium, but easily dissociates if calcium is removed. When C1 is activated the C1r and C1s subunits are each cleaved into two chain molecules due to proteolytic activation. Thus, the SDS gel pattern of C1 is very complex. Function The biological functions of C1q are described above in the General Description and Physical Characteristics sections. C1q functional activity may be assayed using C1q-depleted serum and EA cells. These assays are extremely sensitive to C1q typically yielding 50% lysis with less than 2 ng C1q in assays measuring the lysis of EA cells. AssaysThe unit of classical pathway activity is the CH50. A similar unit, the C1qH50, is used to quantitate the activity of C1q. A C1qH50 unit is the amount of functional C1q needed to lyse 50% of 3×10^7 EA cells (antibody-sensitized sheep erythrocytes) when that amount of C1q is incubated with 5-20 µL of C1q-Dpl in GVB++ in a total volume of 500 µL for 30 min at 37℃. This amount of C1q indicates the sensitivity of the assay for C1q which is typically about 1 ng C1q with 10 µL C1q-Dpl. See the Certificate of Analysis for lot specific values.ApplicationsC1q is used to coat ELISA plates to capture and quantitate immune complexes in clinical samples. A number of commercial companies sell diagnostic kits for immune complex detection and quantitation. These kits are based on the ability of C1q to bind well to immune complexes, but to not bind significantly to monomeric immunoglobulins. GeneticsThe EMBL/Genbank cDNA accession numbers are: C1q A chain (P02745), C1q B chain (P02746), and C1q C chain (P02747). The genes for C1q chains A, B and C are all located on chromosome 1p in the order A-C-B. DeficienciesDeficiencies of each of the three components of C1 have been found. Patients lacking C1q generally have immune-complex-mediated renal disease and skin lesions. Like all patients lacking early classical pathway components C1q deficient individuals are prone to systemic lupus erythrematosis (SLE) and recurrent pyogenic infections. They lack classical pathway function and may or may not exhibit C1q antigen in blood.DiseasesSee section titled Deficiencies above. Precautions/Toxicity/HazardsThis protein is purified from human serum and therefore precautions appropriate for handling any blood-derived product must be used 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... Read More | Product contentF665766Component5 mLStorageF665766A2×Fast Probe Mixture5×1 mL-20℃. Avoid freeze/thaw cycle.F665766BddH2O5×1 mL-20℃. Avoid freeze/thaw cycle.Product IntroductionFast Probe Mixture is a pre-mixed system for real-time fluorescence PCR by probe method (TaqMan, Product contentF665766Component5 mLStorageF665766A2×Fast Probe Mixture5×1 mL-20℃. Avoid freeze/thaw cycle.F665766BddH2O5×1 mL-20℃. Avoid freeze/thaw cycle.Product IntroductionFast Probe Mixture is a pre-mixed system for real-time fluorescence PCR by probe method (TaqMan, Molecular Beacon, etc.), with a concentration of 2×, including Fast Taq DNA Polymerase, PCR Buffer, dNTPs, Mg2+ and so on, which is easy and convenient to operate. It is mainly used for the detection of genomic DNA target sequence and cDNA target sequence after RNA reverse transcription. The Fast Taq DNA Polymerase contained in this product can effectively reduce the non-specific amplification generated by the non-specific binding of primers and templates or primer dimerization at room temperature, and the activation of the enzyme only needs to be incubated at 95 ℃ for 30 s. The whole PCR reaction process can save about 40 minutes compared with the ordinary reaction, which greatly shortens the reaction time of PCR. The combination of unique PCR buffer system and fast hot start enzyme effectively inhibits the generation of non-specific products and significantly improves the PCR amplification efficiency with stronger fluorescence signal, higher sensitivity and wider linear range. The product has a wide range of applications and can be used for both normal and rapid quantitative PCR programs.ROX dye is used to correct the fluorescence signal error generated between wells of a quantitative PCR instrument, and is generally used in Real Time PCR amplifiers from ABI, Stratagene, and other companies. The excitation optics vary from instrument to instrument, so the concentration of ROX dye must be matched to the corresponding fluorescence quantitative PCR instrument.Instruments that do not require ROX calibration (F665766):Roche LightCycler 480, Roche LightCyler 96, Bio-rad iCyler iQ, iQ5, CFX96 and others.Instruments that require Low ROX calibration (F665768):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, and more.Instruments that require High ROX calibration (F665774):ABI Prism 7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, and others.matters needing attention1. Before use, please mix gently by turning up and down, avoid foaming as much as possible, and use after brief centrifugation.2. Avoid repeated freezing and thawing of this product, repeated freezing and thawing may degrade the product performance. This product can be stored for long term at -20℃, protected from light. If frequent use is required within a short period of time, it can be stored at 2-8℃.UsageThe following examples are conventional PCR reaction systems and reaction conditions, which should be improved and optimized according to the template, primer structure and target fragment size in actual operation.1.PCR reaction systemReagents50 µl Reaction systemFinal concentration2×Fast Probe Mixture25 µl1×Forward Primer，10 µM1 µl0.2 µM¹⁾Reverse Primer，10 µM1 µl0.2 µM¹⁾Probe，10 µM1 µl0.2 µM²⁾Template DNA2 µl³⁾ 50×Low ROX or High ROX（optional）⁴⁾1 µl1×ddH₂Oup to 50 µlNote: 1) Usually the primer concentration of 0.2µM can get better results, and 0.1-1.0µM can be used as a reference for setting the range. 2) The final 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, so please refer to the instruction manual of the instrument or the specific requirements of the use of each fluorescent probe for the adjustment of the concentration in actual use.(3) Usually the amount of DNA template is 10-100ng genomic DNA or 1-10ng cDNA as a reference. Since the templates of different species contain different copy numbers of target genes, the templates can be subjected to gradient dilution to determine the optimal amount of template to be used.(4) The excitation optical system varies from instrument to instrument, choose to add 50×Low ROX or 50×High ROX according to the instrument using fluorescence quantification.2. PCR reaction program:A two-step PCR reaction program is recommended, and this program is set up using the ABI 7500 Fluorescent Quantitative PCR Instrument as a reference.Note: 1) The enzyme used in this product must be pre-denatured at 95°C for 30s to achieve enzyme activation. Under this condition, most of the templates can be well unchained. For templates with high GC content and complex secondary structure, the pre-denaturation time can be extended to 1-4 minutes in order to make the starting template fully unchained.(2) It is recommended to use two-step PCR reaction program, if you can not get good experimental results due to the use of primers with lower Tm values, etc., you can try to carry out a three-step PCR amplification, annealing temperature, please use the range of 56 ℃ - 64 ℃ for as a reference for the setting... Read More | Ribonuclease T1 is an endoribonuclease, highly specific for the cleavage of RNA or deaminated RNA between guanosine 3'-phosphate residues (or inosine 3'-phosphate) and the 5'-OH residues of adjacent nucleotides with the formation of the corresponding intermediate 2', 3'-cyclic phosphates. It cleavesRibonuclease T1 is an endoribonuclease, highly specific for the cleavage of RNA or deaminated RNA between guanosine 3'-phosphate residues (or inosine 3'-phosphate) and the 5'-OH residues of adjacent nucleotides with the formation of the corresponding intermediate 2', 3'-cyclic phosphates. It cleaves single-stranded RNA releasing oligonucleotides from the guanosine 3'-phosphate termini. The enzyme has a molecular weight of 11 kDa. The optimum pH is 7.5. RNase T1 is inhibited by Ag+, Zn2+, Cu2+, and Hg2+ at 1 X 10-3 M. The stimulatory effects of both histidine and EDTA are attributed to chelation of contaminating inhibitor cations. The enzyme assay is essentially the method of Egami et al., Prog. in Nucleic Acid Res. and Molec. Biol., III, 59 (1964) based upon the release of acid soluble oligonucleotides following the digestion of yeast RNA.Ribonuclease T1 (RNase T1) from Aspergillus oryzae is used to digest denatured RNA prior to sequencing and is used for protein folding studies. ApplicationRibonuclease T1 has extensive applications in molecular cloning and DNA sequencing. Because of its specificity it has been a commonly used cleavage enzyme for the determination of structure, nearest neighbor frequencies, and RNA sequencing. The enzyme has further application in the preparation of nucleoside 2',3'-cyclic phosphates, the synthesis of oligonucleotides, and the removal of RNA from DNA preparations. The enzyme is also used as a non-mammalian source of RNase in various applications... Read More |