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Cancer/Testis Antigen PASD1 Silences the Circadian Clock
Alicia K Michael1, Stacy L Harvey1, Patrick J Sammons1
1Department of Chemistry and Biochemistry, University of California, Santa Cruz, Santa Cruz, CA 95064, USA.
The cancer/testis antigen PASD1 suppresses daily circadian rhythms by interacting with the CLOCK:BMAL1 complex. Oncogenic transformation can induce PASD1, linking cancer to disrupted circadian rhythms.
Area of Science:
- Molecular biology
- Chronobiology
- Cancer research
Background:
- The circadian clock regulates daily gene expression via the CLOCK:BMAL1 transcription factor.
- Homologous repressors modulate other bHLH-PAS transcription factor pathways, but none were known for CLOCK:BMAL1.
Purpose of the Study:
- To identify a repressor for the CLOCK:BMAL1 complex.
- To investigate the role of the cancer/testis antigen PASD1 in circadian rhythm regulation.
- To explore the link between oncogenic transformation and circadian rhythm disruption.
Main Methods:
- Investigated the interaction between PASD1 and the CLOCK:BMAL1 complex.
- Analyzed PASD1 expression patterns in healthy and cancerous tissues.
- Assessed the impact of PASD1 reduction on circadian transcriptional oscillations in human cancer cells.
Main Results:
- PASD1 acts as a repressor of circadian rhythms by interacting with CLOCK:BMAL1.
- PASD1 expression is normally restricted to germline tissues but is induced in somatic cells during oncogenic transformation.
- Reducing PASD1 levels in human cancer cells enhanced the amplitude of circadian transcriptional oscillations.
Conclusions:
- PASD1 is a novel, germline-specific repressor of the circadian clock.
- PASD1 provides a molecular link between oncogenic transformation and the suppression of circadian rhythms.
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