Isolation and characterization of the SPT2 gene, a negative regulator of Ty-controlled yeast gene expression.
The his4-917 mutation of Saccharomyces cerevisiae results from the insertion of the Ty element Ty917 into the regulatory region of the HIS4 gene and renders the cell His-. The hist4-912 delta mutant, which carries a solo delta in the 5'-noncoding region of HIS4, is His+ at 37 degrees C but His- at 23 degrees C. Both these mutations interfere with HIS4 expression at the transcriptional level. The His- phenotype of both insertion mutations is suppressed by mutations at the SPT2 locus. The product of the wild-type SPT2 gene apparently represses HIS4 transcription in these mutant strains; this repression is relieved when the SPT2 gene is destroyed by mutation. The repression of transcription by SPT2 presumably results from an interaction between the SPT2+ gene product and Ty or delta sequences. In this paper, we report the cloning and DNA sequence analysis of the wild-type SPT2 gene and show that the gene is capable of encoding a protein of 333 amino acids in length. In addition, we show that a dominant mutation of the SPT2 gene results from the generation of an ochre codon which is presumed to lead to a shortened SPT2 gene product.
Roeder
G S
GS
Beard
C
C
Smith
M
M
Keranen
S
S
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D003062:Codon; D004262:DNA Restriction Enzymes; D004251:DNA Transposable Elements; D004271:DNA, Fungal / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics; D005786:Gene Expression Regulation; D005800:Genes, Fungal; D005809:Genes, Regulator; D006639:Histidine / Q000235:genetics; D009154:Mutation; D014158:Transcription, Genetic
D003062:Codon; D004251:DNA Transposable Elements; D004271:DNA, Fungal; D005656:Fungal Proteins; D006639:Histidine; D004262:DNA Restriction Enzymes