Disease relevance of OLI1

• Male-sterility induction in transgenic tobacco plants with an unedited atp9 mitochondrial gene from wheat [1].

High impact information on OLI1

• Assuming that the editing process in higher plant mitochondria reflects a requirement for producing active proteins, we have used edited and unedited coding sequences of wheat ATP synthase subunit 9 (atp9) fused to the coding sequence of a yeast coxIV transit peptide [1].
• Transgenic plants containing unedited atp9 exhibited either fertile, semifertile, or male-sterile phenotypes; controls containing edited atp9 or only the selectable marker gave fertile plants [1].
• The ATP binding cassette (ABC) transporter protein Yor1p was identified on the basis of its ability to elevate oligomycin resistance when it was overproduced from a high-copy-number plasmid [2].
• However, PDR5 is not required for oligomycin resistance [3].
• The presence of the oli1 leader sequence confers stability to the RNA and circumvents the CBP1 processing function [4].

Biological context of OLI1

• The spectra of enzyme-sensitive sites and single-strand breaks induced by MB in vitro or by RO plus light in vivo or in vitro were examined in two yeast reporter genes: the nuclear MFA2 and the mitochondrial OLI1 [5].
• Assembly of the mitochondrial membrane system: mutations in the pho2 locus of the mitochondrial genome of Saccharomyces cerevisiae [6].
• Genetics of oxidative phosphorylation: mitochondrial loci determining ossamycin-, venturicidin- and oligomycin-resistance in yeast [7].
• DNA sequence analysis of mtDNA from strain h45 reveals an additional T residue inserted 88 bp upstream of the oli1 coding region, in the A,T-rich sequence that is transcribed into the 5'-untranslated region of the oli1 mRNA [8].
• Biogenesis of mitochondria: a mutation in the 5'-untranslated region of yeast mitochondrial oli1 mRNA leading to impairment in translation of subunit 9 of the mitochondrial ATPase complex [8].

Anatomical context of OLI1

• CBP1 function is required for stability of a hybrid cob-oli1 transcript in yeast mitochondria [9].
• The plasma membrane ATP-binding cassette (ABC) transporter Yor1p mediates oligomycin resistance in Saccharomyces cerevisiae [10].
• The C2 (Ca2+ and phospholipid-binding sequence) domain of Psd2p, and the lipid-binding protein PstB2p (PtdSer transport B pathway protein encoded by the PSTB2 gene that complements the pstB2 mutation affecting PtdSer transport), must be present on acceptor membranes for PtdSer transport to occur [11].

Associations of OLI1 with chemical compounds

• Recombination studies showed that the two mitochondrial mucidin loci were not allelic with other mitochondrial loci RIB1, RIB2 and OLI1 [12].
• Importantly, transcript levels from the mitochondrial OLI1 gene, which has an associated organellar UAS, were attenuated in the DeltaYJR127C mutant during glycerol-based growth, but those from COX3 (OXI2), which lacks an associated mitochondrial UAS, were not [13].
• We identified initiation sites for the 21 S and 14 S rRNAs; the phenylalanine, f-methionine, and glutamic tRNAs; two sites for the OLI-1 gene; and three for the ori (rep) regions [14].
• Examples are multigene transcripts for the glutamic tRNA and COB genes and for the OLI-1, serine tRNA, and Var genes [14].
• It is inferred that the suppressing mutation in the 5' untranslated region of oli1 mRNA restores subunit 9 biosynthesis by accommodating the modified structure of Aep2p generated by the aep2-ts1 mutation (shown here to cause the substitution of proline for leucine at residue 413 of Aep2p) [15].

Physical interactions of OLI1

• In the present study, we demonstrate that Yrr1p also mediates oligomycin resistance through activation of the ATP-binding cassette transporter-encoding gene YOR1 [16].

Regulatory relationships of OLI1

• Mutations in CBP1 can be suppressed by a p- genome in which the 5' untranslated leader of the oli1 gene (subunit 9 of the ATPase) is fused near the 5' side of the cytochrome b coding sequence [4].

Other interactions of OLI1

• 3. Mutations in COB 1 have been found to be linked to the OLI1 locus in some but not in other strains of S. cervisiae [17].
• Characterization of a second nuclear gene, AEP1, required for expression of the mitochondrial OLI1 gene in Saccharomyces cerevisiae [18].
• The molecular weight of these fragments depends on the map position of the mutant, increasing in the direction OLI2 leads to OLI1 [19].
• In vitro RNA footprint and deletion experiments have been used to define the p40-binding site on the leaders of COX1 and ATP9 mRNAs [20].
• Mutations in the nuclear AEP2 gene of Saccharomyces generate greatly reduced levels of the mature form of mitochondrial oli1 mRNA, encoding subunit 9 of mitochondrial ATP synthase [15].

Analytical, diagnostic and therapeutic context of OLI1

• The three mitochondrion-encoded suppressors were localized to the oli1 region of mtDNA using rho- genetic mapping techniques coupled with PCR analysis; DNA sequencing revealed, in each case, a T-to-C nucleotide transition in mtDNA 16 nucleotides upstream of the oli1 reading frame [15].
• Amino acid substitutions in subunit 9 of the mitochondrial ATPase complex of Saccharomyces cerevisiae. Sequence analysis of a series of revertants of an oli1 mit- mutant carrying an amino acid substitution in the hydrophilic loop of subunit 9 [21].

References