Simple identification of dominant p53 mutants by a yeast functional assay.
Analysis of families with germline p53 mutations shows that the mutant p53 allele behaves as a dominant oncogene at the genetic level, although it behaves as a recessive oncogene at the cellular level, since tumours invariably show mutation or loss of both wild-type alleles. At the biochemical level it is possible that some clinically important mutant p53 proteins may be carcinogenic through a dominant mechanism. We show that p53 mutants can be readily classified according to their dominant potential using a simple yeast functional assay. Wild-type p53 is constitutively expressed from a TRP1 vector, p53 mutants are expressed from an otherwise identical LEU2 vector and net transcriptional activity is scored using an ADE2-based reporter. Twenty seven p53 mutants were tested: 19 were recessive, i.e. gave white colonies, and eight showed dominant activity, i.e. gave pink/red colonies. This simple assay should facilitate studies on p53 dominance.
Inga
A
A
CSTA-Mutagenesis Laboratory, National Institute for Research on Cancer (IST), Genova, Italy.
Cresta
S
S
Monti
P
P
Aprile
A
A
Scott
G
G
Abbondandolo
A
A
Iggo
R
R
Fronza
G
G
D018076:DNA, Complementary / Q000235:genetics; D005799:Genes, Dominant / Q000235:genetics*; D005808:Genes, Recessive / Q000235:genetics; D016158:Genes, p53 / Q000235:genetics*; D005822:Genetic Vectors / Q000235:genetics*; D006801:Humans; D009154:Mutation / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development
D018076:DNA, Complementary