AlkB restores the biological function of mRNA and tRNA inactivated by chemical methylation

Mol Cell. 2004 Oct 8;16(1):107-16. doi: 10.1016/j.molcel.2004.09.002.

Abstract

Deleterious 1-methyladenine (1-meA) and 3-methylcytosine (3-meC) lesions are introduced into nucleic acids by methylating agents. It was recently demonstrated that the E. coli AlkB protein and a human homolog, hABH3, can demethylate these lesions both in DNA and RNA. To elucidate the biological significance of the RNA repair, we have tested whether such repair can rescue the function of chemically methylated RNA. We demonstrate that a methylation-induced block in translation of an mRNA can be readily relieved by treatment with AlkB and hABH3 prior to translation. Furthermore, we show that chemical methylation of tRNAPhe inhibits aminoacylation and translation, but that the inhibition can be reversed by AlkB and hABH3. AlkB-mediated repair of 1-meA in tRNA was also observed in E. coli in vivo. Our data demonstrate that AlkB proteins can mediate functional recovery of RNA exposed to methylation damage, supporting the notion that RNA repair is important.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • AlkB Homolog 1, Histone H2a Dioxygenase
  • AlkB Homolog 3, Alpha-Ketoglutarate-Dependent Dioxygenase
  • DNA Repair Enzymes
  • DNA-Binding Proteins / metabolism
  • Dioxygenases
  • Escherichia coli Proteins / metabolism*
  • Humans
  • Methylation
  • Mixed Function Oxygenases / metabolism*
  • RNA, Messenger / metabolism*
  • RNA, Transfer / metabolism*
  • Sequence Analysis, RNA

Substances

  • DNA-Binding Proteins
  • Escherichia coli Proteins
  • RNA, Messenger
  • RNA, Transfer
  • Mixed Function Oxygenases
  • Dioxygenases
  • ALKBH3 protein, human
  • AlkB Homolog 3, Alpha-Ketoglutarate-Dependent Dioxygenase
  • AlkB protein, E coli
  • ALKBH1 protein, human
  • AlkB Homolog 1, Histone H2a Dioxygenase
  • DNA Repair Enzymes