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Updated: May 15, 2026
10:28
Repressing Gene Transcription by Redirecting Cellular Machinery with Chemical Epigenetic Modifiers
Published on: September 20, 2018
G9a, a multipotent regulator of gene expression.
Shilpa Rani Shankar1, Avinash G Bahirvani, Vinay Kumar Rao
1Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
Epigenetics
|December 22, 2012
Summary
The methyltransferase G9a, known for gene repression, also activates gene expression via novel mechanisms. Its complex roles in development and disease highlight its potential as a therapeutic target.
Area of Science:
- Molecular Biology
- Epigenetics
- Gene Regulation
Background:
- The enzyme G9a catalyzes lysine methylation, primarily linked to transcriptional repression.
- Emerging evidence reveals G9a's non-canonical roles in gene activation, independent of its methyltransferase function.
Purpose of the Study:
- To review the diverse molecular mechanisms and substrates involved in G9a-mediated gene regulation.
- To discuss the multifaceted roles of G9a in biological processes and disease.
Main Methods:
- Literature review of recent studies on G9a function.
- Analysis of molecular pathways and protein substrates regulated by G9a.
- Synthesis of evidence regarding G9a's involvement in development and disease.
Main Results:
- G9a regulates gene expression through both canonical repression and non-canonical activation pathways.
- G9a substrates include histones and non-histone proteins, influencing various cellular processes.
- G9a plays critical roles in cell development, pluripotency, differentiation, and cell cycle control.
Conclusions:
- G9a exhibits complex and context-dependent functions in gene regulation.
- Dysregulated G9a expression is implicated in various human pathologies, including cancer.
- G9a represents a promising therapeutic target for treating diverse diseases.
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