Induction and characterization of morphologic mutants in a natural Saccharomyces cerevisiae strain.
Saccharomyces cerevisiae is a good model with which to study the effects of morphologic differentiation on the ecological behaviour of fungi. In this work, 33 morphologic mutants of a natural strain of S. cerevisiae, obtained with UV mutagenesis, were selected for their streak shape and cell shape on rich medium. Two of them, showing both high sporulation proficiency and constitutive pseudohyphal growth, were analysed from a genetic and physiologic point of view. Each mutant carries a recessive monogenic mutation, and the two mutations reside in unlinked genes. Flocculation ability and responsiveness to different stimuli distinguished the two mutants. Growth at 37 degrees C affected the cell but not the colony morphology, suggesting that these two phenotypes are regulated differently. The effect of ethidium bromide, which affects mitochondrial DNA replication, suggested a possible "retrograde action" of mitochondria in pseudohyphal growth.
Barberio
Claudia
C
Department of Animal Biology and Genetics, University of Florence, via Romana 17, I-50125 Firenze, Italy.
Bianchi
Lucia
L
Pinzauti
Francesca
F
Lodi
Tiziana
T
Ferrero
Iliana
I
Polsinelli
Mario
M
Casalone
Enrico
E
D000968:Antimycin A / Q000494:pharmacology; D002701:Chloramphenicol / Q000494:pharmacology; D004996:Ethidium / Q000494:pharmacology; D008928:Mitochondria / Q000502:physiology; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D013172:Spores, Fungal / Q000502:physiology
D000968:Antimycin A; D002701:Chloramphenicol; D004996:Ethidium