Stuart Brody
e-mail: sbrody@ucsd.edu |
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Studies on the biochemical genetics of Neurospora focus on two topics: Circadian rhythms and Mitochondrial lipid synthesis.
CIRCADIAN RHYTHMS
This rhythm is visibly expressed in Neurospora
as a spore-forming rhythm in a petri dish (see photo below). Areas
of the culture showing the developmental phenomena of spore formation
can be seen as "bands" on the surface of the agar. Mutations affecting
the rhythm lead to different numbers of bands on a plate as seen
in the cla-1 strain below.
We are investigating the effects of several classes of mutations in lipid biosynthesis on properties of the rhythm, namely period and temperature response. One class of mutants is blocked in saturated fatty acid synthesis, another in the formation of mono-unsaturated fatty acids, and a third in the formation of poly-unsaturated fatty acids. The effects of different temperature regimes on the period and phase of the rhythm in these three different classes of mutants are being assayed. Companion studies on the lipid composition of these strains are being undertaken since some of these mutants have large effects on the circadian pacemaker, and since the actual biochemical mechanism of the clock is still not known.
MITOCHONDRIAL LIPID BIOSYNTHESIS
Following our discovery in the mitochondria
of acyl carrier protein (ACP), a key component for fatty acid synthesis,
several lines of investigation are being pursued. The nature of
the internally synthesized fatty acid molecules and their ultimate
destination in the mitochondria is being studied. Since the absence
of ACP leads to dysfunctional mitochondria (as measured by respiration
and assembly of the enzyme complexes), we are studying the role
of these lipid molecules. Mutants lacking ACP in Neurospora
and in S. cerevisiae are now available and will be employed,
as well as certain other petite mutants lacking a key component
of this "internal fatty acid pipeline".
Lakin-Thomas, P.L. and S. Brody (2000). Circadian rhythms in Neurospora crassa: Lipid deficiencies restore robust rhymicity to frq null and white-collar mutants. Proc. Natl. Acad. Sci. USA 97:256-261.
Shaw, J. and S. Brody. (2000). Circadian rhythms in Neurospora: A new measurement, the Reset Zone. J. Biol. Rhythms 15:225-240.
Granshaw, T., Tsukamoto, M., and S. Brody. ( 2003). Circadian Rhythms in Neurospora crassa: Farnesol or geraniol allow expression of rhythmicity in the otherwise arrhythmic strains frq10, wc-1 and wc-2. J.Biol. Rhythms. 18, 287-296.
Lakin-Thomas, P.L. and S. Brody. ( 2004). Circadian Rhythms in Microorganisms : New Complexities. Ann. Review of Microbiol. 58: 489-519.
Brody, S. ( 2005). Genetics and Kinetics. Fungal Genetics and Biology. 42: 81-96.
Lombardi, L.M. and S. Brody (2005). Circadian Rhythms in Neurospora crassa: Clock gene homologues in fungi. Fungal Genetics and Biology. 42: 887-892.
Stuart Brody received his Ph.D. from Stanford University and was a postdoctoral fellow and assistant professor at Rockefeller University. Professor Brody was a recipient of an NIH Career Development Award from 1974 to 1979.
