Premium
Complete sequence of a eukaryotic regulatory gene.
Author(s) -
Hubert J.C.,
Guyonvarch A.,
Kammerer B.,
Exinger F.,
Liljelund P.,
Lacroute F.
Publication year - 1983
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1002/j.1460-2075.1983.tb01702.x
Subject(s) - biology , gene , genetics , sequence (biology) , computational biology , regulatory sequence , regulator gene , regulation of gene expression , evolutionary biology
Dihydroorotase, the third enzymatic activity of the pyrimidine pathway, is encoded in Saccharomyces cerevisiae by a single gene URA4, which is induced at the transcriptional level by accumulation of ureidosuccinic acid. A regulatory gene PPR2 (pyrimidine pathway regulatory 2) acting specifically on this step, has been characterized, cloned and sequenced. The main open reading frame is 384 nucleotides long and potentially codes for a basic protein, favoring a molecular mechanism involving direct binding of a regulatory protein to DNA. The short length of the PPR2 polypeptide chain and the presence of seven cysteine residues suggest that the active form of the protein is an oligomer assembled through disulphide bonds. An uninducible allele has been cloned and sequenced. The mutation corresponds to an A leads to T transversion changing a lysine triplet into an ochre codon. The uninducible phenotype of this mutant is completely suppressed by an ochre suppressor, strengthening the hypothesis that PPR2 acts on URA4 transcription through the synthesis of a regulatory protein.