A Drosophila MBD family member is a transcriptional corepressor associated with specific genes

Eur J Biochem. 2001 Oct;268(20):5397-406. doi: 10.1046/j.0014-2956.2001.02480.x.

Abstract

DNA methylation in Drosophila melanogaster is restricted temporally during development and occurs at a significantly lower frequency than in mammals. Thus, the regulatory functions, if any, of this form of DNA modification in Drosophila are unclear. However, the presence of homologs of vertebrate methyl-CpG-binding proteins implies functional consequences for DNA methylation in flies. This work describes the properties of dMBD-like, a Drosophila homolog of vertebrate MBD2 and MBD3. dMBD-like and dMBD-likeDelta (a splice variant) failed to bind model methylated DNA probes, inconsistent with their function as mediators of methyl CpG-directed transcriptional repression. However, the MBD-like proteins exhibit transcriptional and biochemical properties consistent with roles as components of a histone deacetylase-dependent corepressor complex similar to the vertebrate Mi-2 complex. The two proteins are differentially expressed during development, suggesting functional specialization. dMBD-like and/or dMBD-likeDelta is present at the chromocenter on larval polytene chromosomes as well as at discrete bands interspersed along the euchromatic chromosome arms, many of which are coincident with known ecdysone-induced loci. This banding pattern suggests gene-specific regulatory functions for dMBD-like and the Drosophila Mi-2 complex.

Publication types

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

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Amino Acid Sequence
  • Animals
  • Chromosomes / chemistry
  • Chromosomes / genetics
  • Cloning, Molecular
  • CpG Islands / genetics*
  • DNA / genetics
  • DNA / metabolism
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Drosophila Proteins / chemistry
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism*
  • Drosophila melanogaster / genetics*
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental
  • Heterochromatin / chemistry
  • Heterochromatin / metabolism
  • Histone Deacetylases / metabolism
  • Molecular Sequence Data
  • Multigene Family / genetics
  • Nucleosomes / metabolism
  • Promoter Regions, Genetic / genetics
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Recombinant Proteins / metabolism
  • Repressor Proteins / chemistry
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Sequence Homology, Amino Acid
  • Substrate Specificity
  • Transcription, Genetic / genetics*

Substances

  • DNA-Binding Proteins
  • Drosophila Proteins
  • Heterochromatin
  • Nucleosomes
  • RNA, Messenger
  • Recombinant Proteins
  • Repressor Proteins
  • DNA
  • Histone Deacetylases
  • Adenosine Triphosphatases