Drosophila PSI controls circadian period and the phase of circadian behavior under temperature cycle via tim splicing

  1. Lauren Foley
  2. Jinli Ling
  3. Radhika Joshi
  4. Naveh Evantal
  5. Sebastian Kadener
  6. Patrick Emery  Is a corresponding author
  1. University of Massachusetts Medical School, United States
  2. The Hebrew University of Jerusalem, Israel
  3. Brandeis University, United States

Abstract

The Drosophila circadian pacemaker consists of transcriptional feedback loops subjected to post-transcriptional and post-translational regulation. While post-translational regulatory mechanisms have been studied in detail, much less is known about circadian post-transcriptional control. Thus, we targeted 364 RNA binding and RNA associated proteins with RNA interference. Among the 43 hits we identified was the alternative splicing regulator P-element somatic inhibitor (PSI). PSI regulates the thermosensitive alternative splicing of timeless (tim), promoting splicing events favored at warm temperature over those increased at cold temperature. Psi downregulation shortens the period of circadian rhythms and advances the phase of circadian behavior under temperature cycle. Interestingly, both phenotypes were suppressed in flies that could produce TIM proteins only from a transgene that cannot form the thermosensitive splicing isoforms. Therefore, we conclude that PSI regulates the period of Drosophila circadian rhythms and circadian behavior phase during temperature cycling through its modulation of the tim splicing pattern.

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All source data are included in this submission

The following previously published data sets were used

Article and author information

Author details

  1. Lauren Foley

    Department of Neurobiology, University of Massachusetts Medical School, Worcester, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jinli Ling

    Department of Neurobiology, University of Massachusetts Medical School, Worcester, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Radhika Joshi

    Department of Neurobiology, University of Massachusetts Medical School, Worcester, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Naveh Evantal

    Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
  5. Sebastian Kadener

    Biology Department, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0080-5987
  6. Patrick Emery

    Department of Neurobiology, University of Massachusetts Medical School, Worcester, United States
    For correspondence
    Patrick.Emery@umassmed.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-5176-6565

Funding

National Institute of General Medical Sciences (1R35GM118087)

  • Patrick Emery

National Institute of General Medical Sciences (1R01GM125859)

  • Sebastian Kadener

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2019, Foley et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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https://doi.org/10.7554/eLife.50063

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