Discovery of a chemical probe for the L3MBTL3 methyllysine reader domain

Nat Chem Biol. 2013 Mar;9(3):184-91. doi: 10.1038/nchembio.1157. Epub 2013 Jan 6.

Abstract

We describe the discovery of UNC1215, a potent and selective chemical probe for the methyllysine (Kme) reading function of L3MBTL3, a member of the malignant brain tumor (MBT) family of chromatin-interacting transcriptional repressors. UNC1215 binds L3MBTL3 with a K(d) of 120 nM, competitively displacing mono- or dimethyllysine-containing peptides, and is greater than 50-fold more potent toward L3MBTL3 than other members of the MBT family while also demonstrating selectivity against more than 200 other reader domains examined. X-ray crystallography identified a unique 2:2 polyvalent mode of interaction between UNC1215 and L3MBTL3. In cells, UNC1215 is nontoxic and directly binds L3MBTL3 via the Kme-binding pocket of the MBT domains. UNC1215 increases the cellular mobility of GFP-L3MBTL3 fusion proteins, and point mutants that disrupt the Kme-binding function of GFP-L3MBTL3 phenocopy the effects of UNC1215 on localization. Finally, UNC1215 was used to reveal a new Kme-dependent interaction of L3MBTL3 with BCLAF1, a protein implicated in DNA damage repair and apoptosis.

Publication types

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

MeSH terms

  • Benzamides / chemistry
  • Benzamides / metabolism
  • Benzamides / pharmacology*
  • Binding, Competitive / drug effects
  • Crystallography, X-Ray
  • DNA-Binding Proteins / antagonists & inhibitors
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / metabolism*
  • Dose-Response Relationship, Drug
  • Drug Discovery*
  • HEK293 Cells
  • Humans
  • Lysine / analogs & derivatives*
  • Lysine / antagonists & inhibitors
  • Lysine / chemistry
  • Lysine / metabolism
  • Models, Molecular
  • Molecular Probes / chemistry
  • Molecular Probes / metabolism
  • Molecular Probes / pharmacology*
  • Molecular Structure
  • Piperidines / chemistry
  • Piperidines / metabolism
  • Piperidines / pharmacology*
  • Protein Structure, Tertiary
  • Repressor Proteins / metabolism
  • Structure-Activity Relationship
  • Tumor Suppressor Proteins / metabolism

Substances

  • BCLAF1 protein, human
  • Benzamides
  • DNA-Binding Proteins
  • L3MBTL3 protein, human
  • Molecular Probes
  • Piperidines
  • Repressor Proteins
  • Tumor Suppressor Proteins
  • UNC1215
  • 2-methyllysine
  • Lysine

Associated data

  • PDB/4FL6
  • PubChem-Substance/160647817
  • PubChem-Substance/160647818
  • PubChem-Substance/160647819
  • PubChem-Substance/160647820
  • PubChem-Substance/160647821