Ribonuclease inhibitor.
Description	Ribonuclease inhibitor (EC 2.7.7.49.) from human placenta inhibits different RNAse A-type enzymes (A, B, C) by binding noncovalently in 1:1 ratio. The enzyme does not inhibit RNase I, T1, T2, H, U1, U2, CL3 or S1 nuclease.
Unit definition	One unit inhibits 5 ng of RNAse A with efficiency of 50% using cyclic 2´,3´ CMP as a substrate.
Reaction conditions	Ribonuclease inhibitor should be added to give a final concentration of 1U/ µl. Presence of 1-10 mM DTT is required for activity. The enzyme can be inactivated by heating (>55°C), high salt concentration (e.g., 7 M urea) or addition of SDS.
Storage	Store at -20°C.
Applications	RNA isolation, cDNA synthesis, in vitro transcription/translation.
Quality control	activity, SDS-PAGE purity,assayed in RT-PCR.
References	1. Blackburn, P. (1979) J. Biol. Chem. 254, 12484.
Catalog #	M8.4	M8.6
Pack size	1.000 U	5.000 U