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Murine RNase Inhibitor
Recombinant Source
Catalog # Size Concentration
M0314L 15,000 units 40,000 units/ml
M0314S 3,000 units 40,000 units/ml
Download:MSDS PDF


  • Improved resistance to oxidation, compared to human/porcine Rnase inhibitor
  • Ideal for reactions where low DTT concentrations are required (e.g. Real-time PCR)
Description:
Murine RNase inhibitor is a 50 kDa recombinant protein of murine origin. The inhibitor specifically inhibits RNases A, B and C. It inhibits RNases by binding noncovalently in a 1:1 ratio with high affinity. It is not effective against RNase 1, RNase T1, S1 Nuclease, RNase H or RNase from Aspergillus. In addition, no inhibition of polymerase activity is observed when RNase Inhibitor is used with Taq DNA Polymerase, AMV or M-MuLV Reverse Transcriptases, or Phage RNA Polymerases (SP6, T7, or T3).

Recombinant murine RNase inhibitor does not contain the pair of cysteines identified in the human version that is very sensitive to oxidation, which causes inactivation of the inhibitor (1). As a result, murine RNase inhibitor has significantly improved resistance to oxidation compared to the human/porcine RNase inhibitors, even under conditions where the DTT concentration is low. Therefore, it is advantageous to use murine RNase inhibitor in reactions where high concentration DTT is adverse to the reaction (eg. Real-time RT-PCR).

Source:
An E. coli strain that carries the Ribonuclease Inhibitor gene from mouse.

Applications:
  • RT-PCR
  • cDNA synthesis
  • In vitro transcription/translation
  • Enzymatic RNA labeling reaction
  • Other applications where the integrity of RNA is important

Reaction & Storage Conditions



Unit Definition:
One unit is defined as the amount of Murine RNase Inhibitor required to inhibit the activity of 5ng of RNase A by 50%. Activity is measured by the inhibition of hydrolysis of cytidine 2, 3’-cyclic monophosphate by RNase A.

Concentration:
40,000 units/ml

Storage Conditions:
20 mM HEPES-KOH
50 mM KCl
8 mM DTT
50% Glycerol


Storage Temperature:
-20°C


Notes


Usage notes:
  1. Since ribonucleases typically retain activity under denaturing conditions, care must be taken to avoid denaturing RNase Inhibitor molecules which have complexed with a ribonuclease. To prevent the release of active ribonuclease, temperatures greater than 50°C and high concentrations of urea or other denaturing agents should be avoided.
  2. The recommended concentration of RNase Inhibitor in a reaction is 1 unit/μl. During assembly of a reaction, RNase Inhibitor should be added before other components that are a possible source of RNase contamination (i.e. enzymes, plasmid from a mini prep.)

Quality Control for Current Lot


Quality control values for a specific lot can be found on the datacard which accompanies each product.

Exonuclease Activity:
Incubation of a 50 μl reaction containing 200 units of Murine RNase Inhibitor with 1 μg of a mixture of single and double-stranded [3H] E. coli DNA (105 cpm/μg) for 4 hours at 37ºC released < 0.5% of the total radioactivity.

Latent RNase Assay:
Heating the Murine RNase Inhibitor for 20 minutes at 65°C, followed by incubation of a 10 μl reaction containing 40 units of RNase Inhibitor with 40 ng of RNA transcript for 4 hours at 37°C resulted in no detectable degradation of RNA as determined by gel electrophoresis.

RNase Assay:
Incubation of a 10 μl reaction containing 40 units of Murine RNase Inhibitor with 40 ng of RNA transcript for 4 hours at 37°C resulted in no detectable degradation of RNA as determined by gel electrophoresis.

Endonuclease Assay:
Incubation of a 10 μl reaction containing 40 units of Murine RNase Inhibitor with 300 ng supercoiled plasmid for 4 hours at 37°C produced no nicked molecules as determined by gel electrophoresis.


References


  1. Kim, B.M. et al. (1999) Protein Science, 8, 430-434.