Asymmetric Inheritance of Oxidatively Damaged Proteins During Cytokinesis

Abstract

Carbonylated proteins were visualized in single cells of the budding yeast Saccharomyces cerevisiae , revealing that they accumulate with replicative age. Furthermore, carbonylated proteins were not inherited by daughter cells during cytokinesis. Mother cells of a yeast strain lacking the sir2 gene, a life-span determinant, failed to retain oxidatively damaged proteins during cytokinesis. These findings suggest that a genetically determined, Sir2p-dependent asymmetric inheritance of oxidatively damaged proteins may contribute to free-radical defense and the fitness of newborn cells.