Evidence map›Paper›PMID 41802061›Full record

ArticleProceedings of the National Academy of Sciences of the United States of America2026

Oligomerization of PER2 as a dynamic mode of regulation of the mammalian circadian clock.

Paulomi Sanyal, Diksha Sharma, Akhila Viswan, Priya Crosby, Vaishali Narayanan, Jackson Baumgartner, Carrie L Partch, Ashok Sekhar

Abstract read
In one paragraph

Article in Proceedings of the National Academy of Sciences of the United States of America, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Paulomi SanyalMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.
Diksha SharmaMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.
Akhila ViswanMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.ORCID 0000-0002-2301-6780
Priya CrosbyDepartment of Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064.
Vaishali NarayananMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.
Jackson BaumgartnerDepartment of Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064.ORCID 0000-0002-0707-7014
Carrie L PartchDepartment of Chemistry & Biochemistry, University of California, Santa Cruz, CA 95064.ORCID 0000-0002-4677-2861
Ashok SekharMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India.ORCID 0000-0002-8628-7799

Funding

Structures and mechanisms of circadian rhythms from cyanobacteria to humansR35GM141849 · NIGMS · UNIVERSITY OF CALIFORNIA SANTA CRUZ · PI PARTCH, CARRIE L · 2021 to 2025
$4.6M
Department of Biotechnology, Ministry of Science and Technology, India (DBT) FellowshipDST | Science and Engineering Research Board (SERB) CRG/2019/003457HHMI (HHMI) Research grantHHS | NIH (NIH) GM141849Indian Institute of Science (IISc) FellowshipIndian Institute of Science (IISc) Startup grantNIGMS NIH HHS R35 GM141849Wellcome TrustWellcome Trust DBT India Alliance (India Alliance) IA/I/18/1/503614
6 · The paper itself

Abstract

PER2 is a central transcriptional regulator in the mammalian circadian clock that closes the negative transcription-translation feedback loop by repressing its own transcription. The balance between the synthesis of PER2 and its degradation is a key factor that determines the circadian period. PER2 stability hinges on antagonistic phosphorylation events-phosphorylation at the familial advanced sleep phase site stabilizes PER2 while phosphorylation at the phosphodegron promotes degradation. The molecular mechanism by which phosphorylation elicits structural changes remains unclear, particularly because the phosphodegron is located in an intrinsically disordered region. Here, we show that the region encompassing the structured PER-ARNT-SIM (PAS) domains of PER2 and the downstream phosphodegron region form a large ~30 subunit homo-oligomer that resembles PER2 microbodies observed in mouse fibroblasts. Oligomerization is an emergent property that requires the cooperative interplay between the ordered PAS domains and the neighboring disordered segment. The phosphodegron is sequestered within this oligomer and inaccessible to Casein Kinase 1 (CK1). Intriguingly, Dark-state Exchange Saturation Transfer NMR experiments reveal that the oligomer coexists with dimeric PER2 and phosphorylation of the phosphodegron by CK1 occurs via this sparsely populated dimer. Using phosphomimetic variants, we then demonstrate that phosphorylation at the phosphodegron region destabilizes the oligomer. Our findings reveal the existence of structural polymorphism in PER2 and establish that oligomerization prevents CK1 from phosphorylating the phosphodegron, while phosphorylation of the dimer opposes oligomerization. This mutually antagonistic switch links structural assembly to posttranslational modifications and provides a mechanism by which phosphorylation tunes PER2 turnover and regulates circadian time-period.

Indexed as

Circadian ClocksPeriod Circadian ProteinsProtein MultimerizationAnimalsHumansMicePhosphorylationPER2 protein, humanPer2 protein, mousePeriod Circadian Proteinsbidirectional switchcircadian clockNMR spectroscopyPER2 oligomerizationphosphorylation

Identifiers

PMID41802061
PMCPMC12994163

What Socratic holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.