Location: Goldbeter, 1995 @ d5d9f34afb60 / goldbeter_1995.cellml

Author:
Catherine Lloyd <c.lloyd@auckland.ac.nz>
Date:
2010-04-16 13:03:22+12:00
Desc:
Fixed broken RDF. Added initial conditions to the varibales calculated from ODEs (by reading off the values from figure 2). Re-tested the model in OpenCell and COR and updated the model curation status - the CellML model does replicate figure 2 completely. The previous curation statement was incorrect as the curator hadn't noticed there were two different scales on the y axis in figure 2.
Permanent Source URI:
https://models.cellml.org/workspace/goldbeter_1995/rawfile/d5d9f34afb60dbb0dd219b6bd4d502d4a25fef02/goldbeter_1995.cellml

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  <title>A Model For Circadian PER Oscillations In Drosophila</title>
  <author>
    <firstname>Catherine</firstname>
          <surname>Lloyd</surname>
    <affiliation>
      <shortaffil>Auckland Bioengineering Institute, The University of Auckland</shortaffil>
    </affiliation>
  </author>
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  <section id="sec_status">
    <title>Model Status</title>
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            This CellML model runs in both OpenCell and COR to reproduce Figure 2 in the original published paper.  The units have been checked and they are consistent.
          </para>
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  <sect1 id="sec_structure">
<title>Model Structure</title>

<para>
ABSTRACT: The mechanism of circadian oscillations in the period protein (PER) in Drosophila is investigated by means of a theoretical model. Taking into account recent experimental observations, the model for the circadian clock is based on multiple phosphorylation of PER and on the negative feedback exerted by PER on the transcription of the period (per) gene. This minimal biochemical model provides a molecular basis for circadian oscillations of the limit cycle type. During oscillations, the peak in per mRNA precedes by several hours the peak in total PER protein. The results support the view that multiple PER phosphorylation introduces times delays which strengthen the capability of negative feedback to produce oscillations. The analysis shows that the rhythm only occurs in a range bounded by two critical values of the maximum rate of PER degradation. A similar result is obtained with respect to the rate of PER transport into the nucleus. The results suggest a tentative explanation for the altered period of per mutants, in terms of variations in the rate of PER degradation.
</para>

<para>
The original paper reference is cited below:
</para>

<para>
A Model for Circadian Oscillations in the Drosophila Period Protein (PER), Albert Goldbeter, 1995, <emphasis>Proceedings of the Royal Society of London, Series B, Biological Sciences</emphasis>, 261, 319-324.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=8587874&amp;dopt=Abstract">PubMed ID: 8587874</ulink>
</para>

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<caption>Schematic diagram of the model for circadian oscillations in PER protein and <emphasis>per</emphasis> mRNA.</caption>
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