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Application of MassSQUIRM for Quantitative Measurements of Lysine Demethylase Activity
Published on: March 11, 2012
Lysine-specific demethylase 2A (KDM2A) normalizes human embryonic stem cell derived keratinocytes
1Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
Summary
High expression of a specific human lysine-specific demethylase 2A (KDM2A) variant, KDM2A-N782, unexpectedly enhances keratinocyte proliferation, contradicting known demethylase activity. This finding reveals complex, opposing roles for KDM2A isoforms.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Lysine-specific demethylase 2A (KDM2A) is known to inhibit cell proliferation by reducing gene expression.
- Human embryonic stem cell-derived Nod keratinocytes exhibit poor proliferation and short lifespan, necessitating strategies for improvement.
Purpose of the Study:
- To investigate the role of KDM2A in improving the proliferation of hES-cell-derived Nod keratinocytes.
- To identify specific KDM2A transcripts or isoforms that influence keratinocyte proliferation.
Main Methods:
- Preparation and analysis of four alternatively spliced KDM2A cDNAs.
- Expression analysis of KDM2A variants in hES-cell-derived Nod keratinocytes.
- Assessment of the impact of KDM2A variants on cell proliferation.
Main Results:
- High expression of the KDM2A gene was found to improve the poor proliferation of Nod keratinocytes.
- Only one of the four alternatively spliced KDM2A cDNAs, KDM2A-N782, stimulated proliferation.
- KDM2A-N782 encodes a 782AA protein with JmjC, CXXC, and Ring domains, but lacks F-box and AMN1 domains.
Conclusions:
- Differentially spliced KDM2A transcripts can lead to opposing cellular outcomes, specifically impacting keratinocyte proliferation.
- KDM2A exhibits complex and context-dependent activities, with specific isoforms like KDM2A-N782 promoting proliferation.
- This study presents critical evidence for the multifaceted functions of KDM2A, challenging previous understandings of its role in gene regulation and cell growth.
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