Yeast major adenylate kinase (Aky2p), encoded by a single gene, occurs in two subcellular compartments, mitochondria and cytoplasm. Only 6-8% of the protein which has no cleavable presequence is imported into the organelle (Bandlow et al. (1988) Eur. J. Biochem. 178, 451-457). In the wild type two AKY2-derived signals (a major and a minor one) were detected by a monospecific antibody after two-dimensional gel electrophoresis and Western blotting. The signals reflected identical electrophoretic mobilities and were absent from an AKY2-disrupted strain suggesting that they were due to differently modified forms of Aky2p. Two similar signals were found in a mutant defective in protein N-acetylation, however, the pI values of both spots were shifted towards alkaline pH by one charge. This indicated that both forms of Aky2p were N-acetylated in the wild type and that their charge difference was not caused by incomplete N-acetylation. This observation furthermore suggested that, in the wild type, two different modifications exist one of which is N-acetylation. The second modification remains unidentified. We analysed the influence of protein N-acetylation on mitochondrial import. Both versions of Aky2p occurred in the cytoplasm and in mitochondria. Their proportion was unchanged in the N-acetylation mutant showing that neither modification affected the efficiency of import of adenylate kinase into mitochondria. It is discussed that N-acetylation occurs during or immediately after translation in the cytoplasm so that import of adenylate kinase may ensue co-translationally.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|