SPT6, AN ESSENTIAL GENE THAT AFFECTS TRANSCRIPTION IN SACCHAROMYCES-CEREVISIAE, ENCODES A NUCLEAR-PROTEIN WITH AN EXTREMELY ACIDIC AMINO TERMINUS

SPT6 is an essential gene of Saccharomyces cerevisiae that appears to play a role in transcription. Mutations in the SPT6 (SSN20, CRE2) gene suppress 8 insertion mutations in the 5′ regions of HIS4 and LYS2 and mutations in cis- and/or trans-acting elements that are required for expression of SUC2 and ADH2. We report here that SPT6 encodes a 170-kilodalton highly charged protein with an extremely acidic amino terminus. By use of an epitope-tagged SPT6 protein, we have determined by indirect immunofluorescence that the SPT6 protein is located in the nucleus.