The SUP35 omnipotent suppressor gene is involved in the maintenance of the non-Mendelian determinant [psi+] in the yeast Saccharomyces cerevisiae.
The SUP35 gene of yeast Saccharomyces cerevisiae encodes a 76.5-kD ribosome-associated protein (Sup35p), the C-terminal part of which exhibits a high degree of similarity to EF-1 alpha elongation factor, while its N-terminal region is unique. Mutations in or overexpression of the SUP35 gene can generate an omnipotent suppressor effect. In the present study the SUP35 wild-type gene was replaced with deletion alleles generated in vitro that encode Sup35p lacking all or a part of the unique N-terminal region. These 5'-deletion alleles lead, in a haploid strain, simultaneously to an antisuppressor effect and to loss of the non-Mendelian determinant [psi+]. The antisuppressor effect is dominant while the elimination of the [psi+] determinant is a recessive trait. A set of the plasmid-borne deletion alleles of the SUP35 gene was tested for the ability to maintain [psi+]. It was shown that the first 114 amino acids of Sup35p are sufficient to maintain the [psi+] determinant. We propose that the Sup35p serves as a trans-acting factor required for the maintenance of [psi+].
Ter-Avanesyan
M D
MD
Institute of Experimental Cardiology, Cardiology Research Center, Moscow, Russia.
Dagkesamanskaya
A R
AR
Kushnirov
V V
VV
Smirnov
V N
VN
D000595:Amino Acid Sequence; D005111:Extrachromosomal Inheritance; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics*; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005799:Genes, Dominant; D005800:Genes, Fungal / Q000235:genetics*; D016153:Genes, Suppressor / Q000235:genetics*; D010445:Peptide Elongation Factors; D010454:Peptide Termination Factors; D010957:Plasmids / Q000235:genetics*; D011328:Prions; D014176:Protein Biosynthesis; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D013329:Structure-Activity Relationship; D013489:Suppression, Genetic; D015534:Trans-Activators
D005656:Fungal Proteins; D010445:Peptide Elongation Factors; D010454:Peptide Termination Factors; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators