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06:07
Continuous Fluorescence-Based Endonuclease-Coupled DNA Methylation Assay to Screen for DNA Methyltransferase Inhibitors
Published on: August 5, 2022
Structural basis for the methylation site specificity of SET7/9
Jean-François Couture1, Evys Collazo, Glenn Hauk
1Department of Biological Chemistry, University of Michigan, 1301 Catherine Road, Ann Arbor, Michigan 48109-0606, USA.
Nature Structural & Molecular Biology
|January 18, 2006
Summary
Human SET7/9 protein methyltransferase recognizes a specific motif to methylate substrates like p53 and histone H3. This finding aids in identifying new protein methylation targets.
Area of Science:
- Biochemistry
- Molecular Biology
- Epigenetics
Background:
- SET7/9 is a protein lysine methyltransferase (PKMT) that modifies key proteins including histone H3, p53, and TAF10.
- Understanding PKMT substrate specificity is crucial for deciphering cellular regulatory mechanisms.
Purpose of the Study:
- To determine the structural and sequence determinants governing SET7/9 substrate specificity.
- To identify novel substrates of the SET7/9 enzyme.
Main Methods:
- X-ray crystallography to solve the SET7/9-TAF10 peptide complex structure.
- In vitro methylation assays using wild-type and mutated substrates.
- Sequence-based motif analysis to predict new substrates.
Main Results:
- The SET7/9 enzyme recognizes a conserved K/R-S/T/A motif preceding the target lysine.
- SET7/9 shows a preference for binding aspartate and asparagine residues C-terminal to the target lysine.
- TAF7 was identified as a novel in vitro substrate of SET7/9, methylated at Lys5.
Conclusions:
- A consensus motif and flanking residue preferences dictate SET7/9 substrate recognition.
- The identified motif is a valuable tool for predicting and discovering new PKMT substrates.
- This work advances the understanding of protein methylation and epigenetic regulation.
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