Old Yellow Enzyme Protects the Actin Cytoskeleton from Oxidative Stress

• DOI: 10.1091/mbc.e04-06-0445
• Publication Date: 2004-08-11T01:23:51Z
• Authors: Brian K. Haarer; David C. Amberg
• Keywords: Actin-binding protein

Old Yellow Enzyme (OYE) has long served as a paradigm for the study of flavin-containing NADPH oxido-reductases and yet its physiological role remained mystery. A two-hybrid interaction between Oye2p actin led us to investigate possible function in cytoskeleton. We found that oye deletion strains have an overly elaborate cytoskeleton cannot be attributed changes concentration but likely reflect stabilization filaments, resulting excessive assembly. Cells expressing mutant act1-123p, which weakened with Oye2p, show comparable defects organization strain can suppressed by overexpression Oye2p. Similarly, mutation either conserved cysteine potential disulfide pair Cys285-Cys374 completely suppresses defect oyeDelta phenotype. Strains lacking Oye are also sensitive oxidative stress induced H2O2, menadione, diamide treatment. Mutation Cys285 or Cys374 sensitivity fact confers super-resistance otherwise wild-type strains. These results suggest damage actin, like been observed irreversibly sickled red blood cells, may general phenomenon OYE functions control redox state thereby maintaining proper plasticity In addition uncovering sought biological Enzyme, these establish cellular part directly specific form (C285-C374 bond formation) actin.