Iron-dependent cleavage of ribosomal RNA during oxidative stress in the yeast Saccharomyces cerevisiae.

ABSTRACT: Stress-induced strand breaks in rRNA have been observed in many organisms, but the mechanisms by which they originate are not well-understood. Here we show that a chemical rather than an enzymatic mechanism initiates rRNA cleavages during oxidative stress in yeast (Saccharomyces cerevisiae). We used cells lacking the mitochondrial glutaredoxin Grx5 to demonstrate that oxidant-induced cleavage formation in 25S rRNA correlates with intracellular iron levels. Sequestering free iron by chemical or genetic means decreased the extent of rRNA degradation and relieved the hypersensitivity of grx5Δ cells to the oxidants. Importantly, subjecting purified ribosomes to an in vitro iron/ascorbate reaction precisely recapitulated the 25S rRNA cleavage pattern observed in cells, indi

SUBMITTER: Zinskie JA 

PROVIDER: S-EPMC6139556 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature