A S-adenosylmethionine methyltransferase-like domain within the essential, Fe-S-containing yeast protein Dre2

CNRS UMR2027, Centre Universitaire, Orsay, France.
FEBS Journal (Impact Factor: 3.99). 04/2012; 279(12):2108-19. DOI: 10.1111/j.1742-4658.2012.08597.x
Source: PubMed

ABSTRACT Yeast Dre2 is an essential Fe-S cluster-containing protein that has been implicated in cytosolic Fe-S protein biogenesis and in cell death regulation in response to oxidative stress. Its absence in yeast can be complemented by the human homologous antiapoptotic protein cytokine-induced apoptosis inhibitor 1 (also known as anamorsin), suggesting at least one common function. Using complementary techniques, we have investigated the biochemical and biophysical properties of Dre2. We show that it contains an N-terminal domain whose structure in solution consists of a stable well-structured monomer with an overall typical S-adenosylmethionine methyltransferase fold lacking two α-helices and a β-strand. The highly conserved C-terminus of Dre2, containing two Fe-S clusters, influences the flexibility of the N-terminal domain. We discuss the hypotheses that the activity of the N-terminal domain could be modulated by the redox activity of Fe-S clusters containing the C-terminus domain in vivo.

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