ARMORED RNA TECHNOLOGY FOR PRODUCTION OF RIBONUCLEASE-RESISTANT VIRAL-RNA CONTROLS AND STANDARDS

The widespread use of sensitive assays for the detection of viral and cellular RNA sequences has created a need for stable, well-characteriz ed controls and standards. We describe the development of a versatile, novel system for creating RNase-resistant RNA. ''Armored RNA'' is a c omplex of MS2 bacteriophage coat protein and RNA produced in Escherich ia call by the induction of an expression plasmid that encodes the coa t protein and an RNA standard sequence, The RNA sequences are complete ly protected from RNase digestion within the bacteriophage-like comple xes, As a prototype, a 172-base consensus sequence from a portion of t he human immunodeficiency virus type I (HIV-I) gag gene was synthesize d and cloned into the packaging vector used to produce the bacteriopha ge-like particles. After production and purification, the resulting HI V-1 Armored RNA particles were shown to be resistant to degradation in human plasma and produced reproducible results in the Amplicor HIV-I Monitor assay for 180 days when stored at -20 degrees C or for 60 days at 4 degrees C. Additionally, Armored RNA preparations are homogeneou s and noninfectious.