Slow Growth and Increased Spontaneous Mutation Frequency in Respiratory Deficient afo1 - Yeast Suppressed by a Dominant Mutation in ATP3.
A yeast deletion mutation in the nuclear-encoded gene, AFO1, which codes for a mitochondrial ribosomal protein, led to slow growth on glucose, the inability to grow on glycerol or ethanol, and loss of mitochondrial DNA and respiration. We noticed that afo1 - yeast readily obtains secondary mutations that suppress aspects of this phenotype, including its growth defect. We characterized and identified a dominant missense suppressor mutation in the ATP3 gene. Comparing isogenic slowly growing rho-zero and rapidly growing suppressed afo1 - strains under carefully controlled fermentation conditions showed that energy charge was not significantly different between strains and was not causal for the observed growth properties. Surprisingly, in a wild-type background, the dominant suppressor allele of ATP3 still allowed respiratory growth but increased the petite frequency. Similarly, a slow-growing respiratory deficient afo1 - strain displayed an about twofold increase in spontaneous frequency of point mutations (comparable to the rho-zero strain) while the suppressed strain showed mutation frequency comparable to the respiratory-competent WT strain. We conclude, that phenotypes that result from afo1 - are mostly explained by rapidly emerging mutations that compensate for the slow growth that typically follows respiratory deficiency.
['Li|Jing|J|', 'Rinnerthaler|Mark|M|0000-0003-1190-0584', 'Hartl|Johannes|J|', 'Weber|Manuela|M|', 'Karl|Thomas|T|', 'Breitenbach-Koller|Hannelore|H|', 'Mülleder|Michael|M|', 'Vowinckel|Jakob|J|', 'Marx|Hans|H|', 'Sauer|Michael|M|', 'Mattanovich|Diethard|D|', 'Ata|Özge|Ö|0000-0001-7157-2039', 'De|Sonakshi|S|', 'Greslehner|Gregor P|GP|', 'Geltinger|Florian|F|', 'Burhans|Bill|B|', 'Grant|Chris|C|', 'Doronina|Victoria|V|', 'Ralser|Meryem|M|', 'Streubel|Maria Karolin|MK|', 'Grabner|Christian|C|', 'Jarolim|Stefanie|S|', 'Moßhammer|Claudia|C|', 'Gourlay|Campbell W|CW|0000-0002-2373-6788', 'Hasek|Jiri|J|', 'Cullen|Paul J|PJ|0000-0002-6703-1480', 'Liti|Gianni|G|', 'Ralser|Markus|M|0000-0001-9535-7413', 'Breitenbach|Michael|M|']
D004272:DNA, Mitochondrial D009154:Mutation D059645:Mutation Rate D012441:Saccharomyces cerevisiae D029701:Saccharomyces cerevisiae Proteins
mutation frequency ATP3 rho-zero Saccharomyces cerevisiae growth velocity