Characterization of the manganese-containing superoxide dismutase and its gene regulation in stress response of Schizosaccharomyces pombe.Biochem Biophys Res Commun. 2001 May 18; 283(4):908-14.BB
Fission yeast Schizosaccharomyces pombe contains two superoxide dismutases (SODs), one in the cytosol and the other in mitochondria. The sod2+ gene encoding putative mitochondrial superoxide dismutase containing manganese (MnSOD) has been isolated. Purification and analysis of the sod2+ gene product revealed that it contained only manganese as a cofactor, thus verified to be a genuine MnSOD. It was localized in mitochondria as expected. Its N-terminal amino acid sequence indicated that the mitochondrial targeting sequence of 21 amino acids was removed. The native form consisted of two identical subunits. The sod2+ expression was induced by external stresses, such as treatments with superoxide generators, high osmolarity, and heat. The induction by these stress treatments depended on Wis1-Spc1 MAPK signal transduction pathway being independent of transcription factors Atf1 or Pap1. The sod2 disruption rendered cells sensitive to various superoxide-generators, heat, and high osmolarity, suggesting that the mitochondrial MnSOD acts as a general defense agent against multiple stresses.