Simultaneous isolation of preparative amounts of RNA and DNA from Trichinella spiralis by cesium trifluoroacetate isopycnic centrifugation.

A rapid method for simultaneously banding preparative amounts of RNA and DNA from Trichinella spiralis muscle larvae by isopycnic centrifugation in cesium trifluoroacetate (CsTFA) is described. Larvae were homogenized in guanidinium isothiocyanate and the DNA, RNA, glycogen, and denatured protein components were isopycnically separated without prior purification. This procedure resulted in the isolation of nucleic acids suitable for molecular biological application. Agarose gel electrophoresis of gradient fractions indicated the separation of undegraded RNA and DNA where total RNA was of sufficient purity to efficiently direct in vitro translation of parasite protein and total DNA was greater than 20 kb in size and sensitive to restriction endonuclease digestion. Oligo (dT)-purified poly(A)+ mRNA was 3.6% of total RNA with greater than 18% conversion to cDNA.