The lability of the products of mitochondrial protein synthesis in Saccharomyces cerevisiae. A novel method for protein half-life determination.
A method for the determination of the half-life of mitochondrial translation products in yeast in vivo is proposed. The method uses inhibitors of cytoplasmic and mitochondrial protein synthesis and is based on double-labelling pulse-chase techniques, the second label being used to estimate 'post-incorporation' during the 'chase'. For the first time the difference between post-incroporation and the widely known recycling of the label is considered. These studies show that, in the turnover of mitochondrial translation products, the problem is of post-incorporation into mitochondria (especially from the cell sap) is predominant. The results obtained with this procedure indicate that the half-life of the products of mitochondrial protein synthesis in yeast at the late-exponential phase is about 60 min. The results suggest that mitochondrial transplantation products are subject to proteolysis to acid-soluble forms.
D002701:Chloramphenicol / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000378:metabolism; D006207:Half-Life; D008722:Methods; D008928:Mitochondria / Q000378:metabolism*; D010101:Oxygen Consumption; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*
D005656:Fungal Proteins; D002701:Chloramphenicol; D003513:Cycloheximide