Temperature compensation and membrane composition in Neurospora crassa
P L Lakin-Thomas1, S Brody, G G Coté
1Department of Zoology, University of Cambridge, England. PL106@mole.bio.cam.ac.uk
Chronobiology International
|September 23, 1997
Summary
Neurospora crassa adjusts its membrane lipid composition in response to temperature changes. Mutations affecting lipid synthesis and the FRQ gene impact circadian rhythm temperature compensation, suggesting a role for membrane function.
Area of Science:
- Molecular Biology
- Chronobiology
- Biochemistry
Background:
- Organisms, including Neurospora crassa, exhibit temperature compensation of circadian rhythms.
- Cellular membranes adjust lipid composition to maintain function across varying temperatures.
- Increased fatty acid unsaturation at lower temperatures is a common response to maintain membrane fluidity.
Purpose of the Study:
- To review the relationship between temperature compensation of the circadian rhythm and temperature-induced adjustments in membrane composition.
- To explore the role of lipid metabolism and specific genes in this process within Neurospora crassa.
Main Methods:
- Review of existing literature on Neurospora crassa's circadian rhythm and membrane composition.
- Analysis of genetic data from mutations affecting temperature compensation (frq, cel, chol-1).
- Investigating the interaction between lipid metabolism genes (cel, chol-1) and the FRQ gene.
Main Results:
- Neurospora crassa modifies its lipid composition, notably fatty acid unsaturation, in response to growth temperature.
- Mutations in cel and chol-1 impair lipid synthesis and affect circadian rhythm temperature compensation.
- The frq mutation interacts with lipid synthesis mutants, implicating the FRQ gene product in membrane function.
Conclusions:
- Lipid metabolism likely plays a significant role in the temperature compensation of the circadian rhythm in Neurospora.
- The FRQ gene product may be involved in regulating membrane lipid composition or sensing changes in it.
- Understanding these mechanisms provides insight into the integration of metabolic and temporal processes at the cellular level.
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