Characterization of a yeast nuclear gene, AEP2, required for accumulation of mitochondrial mRNA encoding subunit 9 of the ATP synthase.
The temperature-conditional pet mutant, ts379, of Saccharomyces cerevisiae fails to synthesize mitochondrial ATP synthase subunit 9 at the restrictive temperature due to mutation of a single nuclear locus, AEP2. The inability to synthesize subunit 9 correlates with a lowered accumulation of the cognate oli1 mRNA indicating that the AEP2 product is involved in oli1 transcript maturation or stabilization. The AEP2 gene has been isolated in this study from a wild-type yeast genomic library by genetic complementation of ts379 at the restrictive temperature. A 1,740 nucleotide open-reading frame was observed that encodes a basic, hydrophilic protein of 67,534 Da which possesses a putative mitochondrial address signal. Disruption of chromosomal DNA within this reading frame produced a non-conditional respiratory mutant unable to synthesize subunit 9, identifying the AEP2 gene. Hybridization analyses indicate that AEP2 is located on chromosome XIII and produces a 2.1 kb poly(A)+ transcript. Two additional open-reading frames were found in close proximity to that of AEP2. The three open-reading frames shared no significant homology with entries in several data bases.
Finnegan
P M
PM
Department of Biochemistry, Monash University, Clayton, Victoria, Australia.
Payne
M J
MJ
Keramidaris
E
E
Lukins
H B
HB
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D006180:Proton-Translocating ATPases / Q000235:genetics* / Q000378:metabolism; D012313:RNA / Q000378:metabolism*; D012331:RNA, Fungal / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D000077278:RNA, Mitochondrial; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D014158:Transcription, Genetic
D004271:DNA, Fungal; D004272:DNA, Mitochondrial; D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D000077278:RNA, Mitochondrial; D012313:RNA; D006180:Proton-Translocating ATPases