TRIzol® Reagent allows the user to perform sequential precipitation of RNA, DNA, and proteins from a single sample
(Chomczynski, 1993). After homogenizing the sample with TRIzol® Reagent, chloroform is added, and the homogenate is allowed
to separate into a clear upper aqueous layer (containing RNA), an interphase, and a red lower organic layer (containing the DNA
and proteins). RNA is precipitated from the aqueous layer with isopropanol. DNA is precipitated from the interphase/organic
layer with ethanol. Protein is precipitated from the phenol-ethanol supernatant by isopropanol precipitation. The precipitated
RNA, DNA, or protein is washed to remove impurities, and then resuspended for use in downstream applications.