5-Methylcytosine (5mC) and 5-Hydroxymethylcytosine (5hmC) Enhance the DNA Binding of CREB1 to the C/EBP Half-Site Tetranucleotide GCAA

Biochemistry. 2016 Dec 13;55(49):6940-6948. doi: 10.1021/acs.biochem.6b00796. Epub 2016 Nov 29.

Abstract

In human and mouse stem cells and brain, 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) can occur outside of CG dinucleotides. Using protein binding microarrays (PBMs) containing 60-mer DNA probes, we evaluated the effect of 5mC and 5hmC on one DNA strand on the double-stranded DNA binding of the mouse B-ZIP transcription factors (TFs) CREB1, ATF1, and JUND. 5mC inhibited binding of CREB1 to the canonical CRE half-site |GTCA but enhanced binding to the C/EBP half-site |GCAA. 5hmC inhibited binding of CREB1 to all 8-mers except TGAT|GCAA, where binding is enhanced. We observed similar DNA binding patterns with ATF1, a closely related B-ZIP domain. In contrast, both 5mC and 5hmC inhibited binding of JUND. These results identify new DNA sequences that are well-bound by CREB1 and ATF1 only when they contain 5mC or 5hmC. Analysis of two X-ray structures examines the consequences of 5mC and 5hmC on DNA binding by CREB and FOS|JUN.

MeSH terms

  • 5-Methylcytosine / analogs & derivatives*
  • 5-Methylcytosine / metabolism*
  • Animals
  • CCAAT-Enhancer-Binding Proteins / metabolism*
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • DNA / metabolism*
  • Mice
  • Promoter Regions, Genetic

Substances

  • CCAAT-Enhancer-Binding Proteins
  • Creb1 protein, mouse
  • Cyclic AMP Response Element-Binding Protein
  • 5-hydroxymethylcytosine
  • 5-Methylcytosine
  • DNA