| Description | EnzymoPure™II M-MLV Reverse Transcriptase (RNase H-) produced by aladdin is an optimized Moloney Murine Leukemia Virus (M-MLV) reverse transcriptase without ribonuclease H (RNase H) activity. It is a DNA polymerase that uses single stranded RNA or DNA as template to synthesize complementary EnzymoPure™II M-MLV Reverse Transcriptase (RNase H-) produced by aladdin is an optimized Moloney Murine Leukemia Virus (M-MLV) reverse transcriptase without ribonuclease H (RNase H) activity. It is a DNA polymerase that uses single stranded RNA or DNA as template to synthesize complementary DNA strands in the presence of primers. It is one of the most widely used reverse transcriptase.sApplication：First strand cDNA synthesis using total RNA or mRNA as template; DNA probe labeling with fluorescence, biotin, digoxin or isotope; RNA analysis by primer extension.This product is highly cost-effective. The RT II M-MLV reverse transcriptase (RNase H-) is a recombinant reverse transcriptase expressed and purified from E. coli transformed with the expression plasmids carrying the pol gene fragment of M-MLV with RNase H coding region removed. The enzyme has been engineered to have better thermal stability and higher reverse transcription activity.Definition of enzyme activity: One unit of the enzyme incorporates 1nmol of dTTP into acid-precipitable material in 10 min at 37℃ using poly(A)•oligo(dT)12-18 as template-primer. The reaction system contains 50mM Tris-HCl (pH8.3), 75mM KCl, 3mM MgCl2, 10mM DTT, 0.5mM [3H]-dTTP and 0.4 mM poly(A)•oligo(dT)12-18.Purity: Free from DNA endonuclease, DNA exonuclease, phosphoesterase and RNase.Enzyme storage buffer: 20mM Tris-HCl (pH7.5), 300mM NaCl, 0.1mM EDTA, 1mM DTT, 0.01%(v/v) NP-40 and 50% (v/v) glycerol.Inactivation or inhibition: RT II M-MLV Reverse Transcriptase (RNase H-) can be inactivated by incubation at 80ºC for 10 minutes, or inhibited by EDTA, EGTA, inorganic phosphates, pyrophosphates and polyamine.This product has high reverse transcription activity, and is able to synthesize long cDNA. The RT II M-MLV Reverse Transcriptase (RNase H-) lacks RNase H activity, and does not degrade the RNA strand of an RNA-DNA hybrid, thus facilitating the synthesis of long cDNA. It can easily synthesize cDNA up to 8kb (Figure 1). The maximum length of synthesized cDNA by this product can exceed 10kb. Figure 1. Agarose gel electrophoresis of PCR products amplified from the cDNA template that was synthesized by the RT II M-MLV reverse transcriptase (RNase H-) (, #). cDNA ranging from 0.2kb to 8kb in length can be synthesized high efficiently.This product exhibits high thermal stability. This product has an optimum working temperature of 42-45ºC, but it is still highly active at 50ºC (Figure 2). Figure 2. Agarose gel electrophoresis of PCR products amplified from the cDNA templates that were synthesized by the RT II M-MLV reverse transcriptase (RNase H-) (, #) and by the M-MLV reverse transcriptase (RNase H-) (Beytome, ), respectively. 500ng of total RNA extracted from NIH3T3 cells was reverse transcribed by reverse transcriptase in a reaction volume of 20µl at difference temperatures as indicated in the figure. One microliter of each reverse transcription reaction product was taken for PCR amplification.The concentration of this product is 200U/µl. When 20µl of reverse transcription reaction volume is used, the S, M and L are sufficient for 50, 250 and 1000 reactions, respectively.Enzyme storage buffer：20mM Tris-HCl (pH7.5), 300mM NaCl, 0.1mM EDTA, 1mM DTT, 0.01%(v/v) NP-40 and 50% (v/v) glycerol.Inactivation or inhibition：RT II M-MLV Reverse Transcriptase (RNase H-) can be inactivated by incubation at 80ºC for 10 minutes, or inhibited by EDTA, EGTA, inorganic phosphates, pyrophosphates and polyamine.This product has high reverse transcription activity, and is able to synthesize long cDNA. The RT II M-MLV Reverse Transcriptase (RNase H-) lacks RNase H activity, and does not degrade the RNA strand of an RNA-DNA hybrid, thus facilitating the synthesis of long cDNA. It can easily synthesize cDNA up to 8kb (Figure 1). The maximum length of synthesized cDNA by this product can exceed 10kb. Figure 1. Agarose gel electrophoresis of PCR products amplified from the cDNA template that was synthesized by the RT II M-MLV reverse transcriptase (RNase H-). cDNA ranging from 0.2kb to 8kb in length can be synthesized high efficiently.This product exhibits high thermal stability. This product has an optimum working temperature of 42-45ºC, but it is still highly active at 50ºC (Figure 2). Figure 2. Agarose gel electrophoresis of PCR products amplified from the cDNA templates that were synthesized by the RT II M-MLV reverse transcriptase (RNase H-) and by the M-MLV reverse transcriptase (RNase H-) (Beytome, D7159), respectively. 500ng of total RNA extracted from NIH3T3 cells was reverse transcribed by reverse transcriptase in a reaction volume of 20µl at difference temperatures as indicated in the figure. One microliter of each reverse transcription reaction product was taken for PCR amplification.The concentration of this product is 200U/µl. When 20µl of reverse transcription reaction volume is used, the D7160S, D7160M and D7160L are sufficient for 50, 250 and 1000 reactions, respectively.Precautions：Please refer to the instructions for reverse transcription of RNAs with high GC content.This product is for R&D only. Not for drug, household, or other uses.For your safety and health, please wear lab coat and disposable gloves during the operation.Instructions for Use：1. First-strand cDNA synthesis.a. Set up the first-strand cDNA synthesis reaction in a nuclease-free PCR tube on ice or at room temperature as follows. RNase Inhibitor and dNTP mix can be purchased from. Template (one of the three types of RNA)Total RNA0.1ng-5µgPoly(A) RNA/mRNA10pg-0.5µgSpecific RNA0.01pg-0.5µgPrimer (one of the three types of primer)Oligo(dT)18 Primer0.5µg (or 100pmol)Random Hexamer Primer0.2µg (or 100pmol)Gene-specific Primer15-25pmol(Optional) For RNAs with high GC content (e.g. ＞55%) or complex secondary structures, incubate the mixture of primer and template at 65ºC for 5 minutes, and immediately put it on ice to disrupt RNA secondary structures.DEPC-treated Water-To 13.7µl*Reaction Buffer (5X)-4µlRNase Inhibitor (40U/µl)-0.5µldNTP Mix (25mM each)-0.8µl**RT II M-MLV Reverse Transcriptase (RNase H-)-1µl***Total Volume-20µl* ‘To 13.7µl’ means filling the mixture of template and primer to a total volume of 13.7µl with DEPC-treated water.** The volume of dNTP mix varies depending on the concentration of dNTP stock. If the volume of dNTP is not 0.8µl, adjust the volume of DEPC-treated water accordingly.*** If gene specific primers or Oligo(dT)18 primers are used to reverse transcribe the cDNA over 5kb, the volume of RT II M-MLV reverse transcriptase (RNase H-) should be increased to 2µl.b. Mix the reaction by vortex or pipetting gently, centrifuge briefly to allow liquid to accumulate at the bottom of PCR tube.c. Incubate the reaction at 42ºC for 60min if Oligo(dT)18 primer or gene-specific primer is used. If random hexamer is used, carry out incubation at 25℃ for 10min, followed by incubation at 42℃ for 60min. Note: For RNA template with high GC content or secondary structures, incubate the reaction at 50℃ for 60min in order to improve the reverse transcription efficiency.d. Stop the reverse transcription by incubating the reaction at 80ºC for 10min to inactivate RT II M-MLV reverse transcriptase (RNase H-). Note: Heat-inactivation of reverse transcriptase is not recommended for long cDNA over 5kb, as this method may cause shearing of long cDNA fragments. In such a case, phenol-chloroform extraction or column purification can be considered.e. The reverse transcription products can be used directly for subsequent experiments such as PCR, or stored at -20℃ for future use. We recommend using 2µl reverse transcription products in a PCR reaction volume of 50µl.2. For other applications such as primer extension and probe labeling, please refer to reference related to M-MuLV reverse transcriptase (RNase H-).FAQ：1. The reverse transcription product of total RNA is invisible after electrophoresis.It is a normal phenomena, because the amount of RNA template is low, and the amount of reverse transcription products in different size is even lower. 2. No specific product can be amplified from the reverse transcription product.a. To exclude the problem of PCR reaction system or reverse transcription product, use gene-specific primers to amplify internal reference genes, such as actin and GAPDH. If reference genes can be amplified but not the target gene, it indicates primers of target gene are not well designed, the expression of the target gene is too low to be detected, or the reverse transcription efficiency is low. b. Template RNA may be degraded. The integrity of total RNA can be checked by agarose gel or on-chip electrophoresis. Intact total RNA exhibits sharp, clear 28S and 18S rRNA bands, and the 28S rRNA band should be approximately twice as intense as the the 18S rRNA band. A ratio less than 2 indicates the degradation of total RNA and new total RNA should be prepared. c. RNA samples may contain some components that inhibit the activity of reverse transcriptase. Those contaminants include phenol, SDS, EDTA, guanidine salts, phosphoric acid, pyrophosphoric acid, polyamine, and spermidine etc, which can be removed effectively by column purification or precipitation, washing, and redissolution. Total RNA extracted by Zol (, #R0011) or Trizol (, #R0016) usually can meet the requirements of reverse transcription.d. Insufficient templates for reverse transcription. When DNase I used to remove the residual DNA in RNA sample is subjected to heat-inactivation prior to reverse transcription, EDTA should be added to RNA sample at a final concentration of 2.5mM to protect RNA from degradation under high temperature. Additionally, to amplify a specific gene, it is necessary to extract RNA from tissues in which the target gene is highly expressed. e. Inappropriate primer is used for reverse transcription. Random hexamer instead of Oligo(dT)18 should be used for the reverse transcription of bacterial total RNA which does not have poly(A) tails. Gene-specific primers used for reverse transcription must be well designed.f. For RNA template with high GC content or secondary structures, increase the reverse transcription temperature to 45-50℃ to improve the reverse transcription efficiency... Read More | Product introduction：Aladdin ® SE is a kind of fluorescent dye with amino reactive activity. The SE group of these dyes can react with the amino group to produce a stable amide bond. Compared with other similar dyes on the market, aladdin ® is a new generation of fluorescent dyes Product introduction：Aladdin ® SE is a kind of fluorescent dye with amino reactive activity. The SE group of these dyes can react with the amino group to produce a stable amide bond. Compared with other similar dyes on the market, aladdin ® is a new generation of fluorescent dyes with stronger stability, better water solubility and better fluorescence intensity. Product parameters： Absmax/Em(nm)：648/664；Absmax/Em(nm)：0.03；Extinction coefficient(ε)：240000；Optimal DOL(IgG)：3-6； Usage:1. Experimental materials(1) IgG: IgG must not contain amine chemicals that can react with dyes, such as amino acids, Tris, BSA, gelatin, etc. If IgG contains such chemicals, PBS buffer with pH~7.4 should be used for pre dialysis treatment. The presence of azide compounds does not affect the labeling reaction.(2) Anhydrous DMSO(3) NaHCO3(4) Sephadex gel G-25 dialysis column(5) PBS buffer (pH~7.4)(6) NaN3(7) BSA2. Marking methods and steps(1) Prepare to label antibodiesDilute the antibody with 0.1 M NaHCO3 solution (pH~8.3) to a final concentration of 2.5 mg/mL. If the product is pre diluted with phosphate buffer, such as PBS buffer (without amino compounds), approximately 1/10 volume of 1M NaHCO3 mother liquor can be directly added to the buffer to achieve a final NaHCO3 concentration of 0.1 M.Note: When the protein concentration is 2.5 mg/mL, the labeling efficiency is approximately 35%. Protein concentrations below 2.5 mg/mL can also be used for labeling, but the labeling efficiency will decrease. When the protein concentration is higher than 5 mg/mL, the labeling efficiency may be higher. Due to differences in buffer and protein purity, more precise labeling efficiency is determined by practical operating conditions. If the protein concentration is too low, it can be concentrated by ultrafiltration.(2) Prepare dye storage solutionPreheat one tube at room temperature µ YF of Mole ® SE, add 0.1 mL of anhydrous DMSO to the tube, thoroughly vortex dissolve the dye, and prepare a dye storage solution with a concentration of 10 mM. If a trace amount of protein is used for labeling reactions, the dye needs to be diluted to a lower concentration.Note: a The remaining dye storage solution should be stored at a low temperature of -20 ℃ for future use. If anhydrous DMSO is used to prepare dye storage solution, the dye can be stored for at least one month.b. Dyes can also be prepared with deionized water, but due to the slow hydrolysis of dyes in water, it is best to prepare water based storage solutions for immediate use.(3) Mark reaction stepsa. Stir or vortex the protein solution, gradually adding 15-25 drops µ L dye storage solution (10 mM), with a molar ratio of dye/protein in the range of 9:1 to 15:1. YF ® Please refer to the table above for the range of DOL (number of dyes bound to each protein molecule) for SE labeled IgG antibodies.b. Stir the reaction at room temperature for 1 hour, and for trace labeling, shake and incubate on a shaker for 1 hour.Note: At the same time of the binding reaction, proceed to step 2 (4) to balance the dextran gel G-25 dialysis column.(4) Isolation of marker proteins from reaction solutiona. PBS buffer (pH~7.4) was used to balance the dextran gel G-25 dialysis column (10 mm × 300 mm).b. Add the reaction solution from step 3 (b) to the column and elute with 1 x PBS buffer.The first washed out chromophore is a dye protein complex.Note: a For small-scale labeling reactions, in order to avoid excessive dilution of the product, ultrafiltration devices can be used to remove free dyes from the complex.b. After the binding reaction is completed, if the dye protein complex is not separated in time, 50 can be added µ Terminate the reaction with L 1M lysine. In most cases, this operation is not necessary because the remaining unreacted dyes have been fully hydrolyzed at the end of the reaction.3. Determine DOL(1) The determination of protein concentration and antibody concentration can be calculated using the following formula:C (mg/mL)={[A280- (Amax x x Cf)]/1.4} x dilution factor;a. C refers to the concentration of antibodies collected in the experiment;b. Dilution factor refers to the dilution factor used in photometric measurements;c. A280 and Amax refer to the absorbance at 280 nm and the absorbance at the absorption wavelength, respectively;d. Cf is the correction factor, YF ® Please refer to the table above for the Cf value of SE dyes;Note: The protein solution eluted through the column may have a high concentration when used directly for absorbance detection, so it needs to be diluted to approximately 0.1 mg/mL. The dilution factor (i.e. dilution factor) needs to be determined from the initial number of antibodies (e.g. 5 mg) and the overall elution of protein solutionEstimate based on the product.(2) Estimation of DOLDOL is calculated using the following equation:DOL=(Amax x x Mwt x Dilution Factor)/（ ε X C)a. Amax, dilution factor, C value has been clearly defined in 3 (1);b. Mwt refers to the molecular weight of IgG (150000);C. c ε It's YF ® The molar absorption coefficient of SE, refer to the table on the first page;d. Mark YF ® The optimal DOL value for SE IgG antibodies can be found in the table on the first page. Although DOL values may fluctuate, good experimental results can also be achieved.Matters needing attention：1. if the labeled protein needs long-term storage, it is recommended to add 5-10 mg/ml BSA and 0.01-0.03% NaN3 to prevent protein denaturation and microbial breeding. Store at 4 ℃ away from light. If glycerol with a final concentration of 50% is added, it can be stored at -20 ℃. It can be stably stored for more than one year. 2. keep away from light during operation. The mixing speed should be appropriate to avoid bubbles. 3. when installing the chromatographic column, try to make the column body uniform, the column surface flat, and free of bubbles and cracks. 4. pay attention to adding the sample when the column top buffer is tangent to the gel plane. When eluting, add the eluent when the sample is tangent to the gel plane. 5. other factors affecting the labeling efficiency also include temperature, reaction time, pH, the amount of fluorescent dye and protein, etc., which should be controlled. 6. for your safety and health, please wear laboratory clothes and disposable gloves.Scope of application：Protein nucleic acid labeling dye... Read More | Inquire | Inquire | Inquire |