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Updated: May 18, 2026
09:11
Assays for Validating Histone Acetyltransferase Inhibitors
Published on: August 6, 2020
CAC1 negatively regulates RARα activity through cooperation with HDAC
MinO Moon1, Soo-Jong Um, Eun-Joo Kim
1Department of Molecular Biology, BK21 Graduate Program, Dankook University, Yongin-si, Gyeonggi-do 448-701, Republic of Korea.
Biochemical and Biophysical Research Communications
|September 18, 2012
Summary
Scientists discovered CDK2-associated cullin (CAC1) as a novel protein that inhibits retinoic acid receptor alpha (RARα) activity. Depleting CAC1 enhances retinoic acid-induced neuronal differentiation, revealing CAC1
Area of Science:
- Molecular Biology
- Developmental Biology
- Cell Biology
Background:
- Retinoic acid (RA) is crucial for cellular differentiation and animal development.
- RA signaling involves retinoic acid receptors (RARs) and retinoid X receptors (RXRs) interacting with coregulators.
- Understanding coregulator function is key to deciphering RA-mediated gene regulation.
Purpose of the Study:
- To identify novel coregulators of RARα.
- To investigate the role of CDK2-associated cullin (CAC1) in RARα transcriptional activity.
- To elucidate CAC1's mechanism of action and its impact on RA-induced differentiation.
Main Methods:
- Co-immunoprecipitation assays to detect protein interactions.
- Reporter gene assays to measure transcriptional activity.
- Western blotting to assess protein levels and cellular differentiation markers.
- RNA interference (RNAi) to deplete CAC1 levels in P19 cells.
Main Results:
- CDK2-associated cullin (CAC1) was identified as a novel RARα coregulator.
- CAC1 directly binds to RARα via its CoRNR box, inhibiting RARα transcriptional activity.
- CAC1 cooperates with histone deacetylases (HDACs) to suppress RARα function.
- Depletion of CAC1 enhances retinoic acid-induced neuronal differentiation in P19 cells, with increased nestin expression.
Conclusions:
- CAC1 acts as a novel corepressor for RARα.
- CAC1's interaction with HDACs is critical for repressing RARα activity.
- CAC1 plays a significant role in regulating retinoic acid-mediated cellular differentiation, particularly neuronal differentiation.
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