Simultaneous banding of rat embryo DNA, RNA, and protein in cesium trifluoroacetate gradients.

A procedure for the simultaneous banding of cellular DNA, RNA, and protein by centrifugation in cesium trifluoroacetate (CsTFA) gradients is described. Starting with homogenates of Day 11 rat embryos, this procedure was used to separate total DNA, RNA, and protein. Under the conditions used DNA banded at a peak density of 1.63 g/ml, RNA at a peak density of 1.83 g/ml, and protein at a peak density of 1.40 g/ml. Nucleic acids isolated from CsTFA gradients were judged to be protein free. RNA isolated by this method is apparently free of DNA contamination; however, DNA isolated by this method does contain some RNA (less than 5% contamination).