Total RNA Extraction from Saccharomyces cerevisiae Using Hot Acid Phenol

Isolation of RNA from yeast is complicated by the need to first break the thick, rigid cell wall. The protocol provided here uses a cycle of heating and freezing of cells in the presence of phenol and the detergent sodium dodecyl sulfate (SDS). The extraction is performed in the presence of low salt so that, following separation of the aqueous and phenol phases by centrifugation, DNA can be collected from the interface while RNA remains in the aqueous phase. This protocol should yield ∼50–250 µg of RNA from 10 mL of culture. The RNA isolated using this approach is suitable for most follow-up applications such as northern blot hybridization, reverse transcriptase-polymerase chain reaction (RT-PCR), and cDNA construction.