A Model For Circadian PER Oscillations In Drosophila
Catherine
Lloyd
Auckland Bioengineering Institute, The University of Auckland
Model Status
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.
Model Structure
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.
The original paper reference is cited below:
A Model for Circadian Oscillations in the Drosophila Period Protein (PER), Albert Goldbeter, 1995, Proceedings of the Royal Society of London, Series B, Biological Sciences, 261, 319-324. PubMed ID: 8587874
reaction diagram
Schematic diagram of the model for circadian oscillations in PER protein and per mRNA.
M
per mRNA
P0
PER protein
P1
phosphorylated PER protein
P2
bisphosphorylated PER protein
PN
nuclear bisphosphorylated PER protein
Pt
total PER protein
2007-06-14T11:56:49+12:00
Auckland Bioengineering Institute, The University of Auckland
James
Lawson
Richard
Catherine
Lloyd
May
This is the CellML description of Albert Goldbeter's 1995 model for circadian oscillations in the Drosophila period protein (PER).
Catherine
Lloyd
May
Albert
Goldbeter
8587874
Albert Goldbeter's 1995 model for circadian oscillations in the
Drosophila period protein (PER).
Drosophila
75
10000
0.01
Fixed link to the correct figure diagram.
added cmeta:id's to variables, changed documentation
2008-08-29T15:07:19+12:00
1995-09-22
A model for circadian oscillations in the Drosophila period protein (PER)
261
319
324
keyword
cell cycle
circadian rhythms
drosophila period protein
drosophila
c.lloyd@auckland.ac.nz
Proceedings of the Royal Society of London series B
2003-10-30T00:00:00+00:00
The University of Auckland
Auckland Bioengineering Institute
Catherine Lloyd