M Økland

..These data suggest that the Neurospora crassa circadian clock regulates an unknown transcription factor, which in turn activates the expression of eas(ccg-2) at specific times of the day...

..Thus even a relatively simple lower eukaryote can be used to address questions about a complex, networked circadian system...

..In both cases, the temporal coordination of a multi-oscillator system is essential for producing robust circadian rhythms of gene expression and biological activity...

..The results are consistent with the presence of 2 circadian oscillators within Neurospora cells, which the authors speculate may interact with each other through the shared WC proteins...

..Thus, the role of the clock in regulation of the activity of MAPK pathways provides important clues into the function of the circadian clock as a tumor suppressor...

..crassa circadian clock allows anticipation and preparation for hyperosmotic stress and desiccation that begin at sunrise. These results suggest a conserved role for MAPK pathways in circadian rhythmicity...

..The authors speculate that the clock system may sense not only light but also the redox potential of the cell through one of the PAS domains of the core clock components WC-1 or WC-2...

..Both pheromone precursor genes are also regulated by the endogenous circadian clock in a time-of-day-specific fashion, supporting a role for the clock in mating...

..Examination of several other phase markers as well as results of additional experimental tests indicate that the FLO is, at best, a slave oscillator to the TTFL, which underlies circadian rhythm generation in Neurospora...

..These data demonstrate that luciferase is a sensitive reporter of gene expression in N. crassa. Our results also show that the modified luciferase is expressed in Aspergillus nidulans...

..Together, these data point to the endogenous clock and the environment following separate pathways to regulate conidiation-specific gene expression...

..crassa. Transcripts of genes for ethanol fermentation and the tricarboxylic acid cycle are abundant in glucose-rich medium, consistent with N. crassa carrying out a high rate of both fermentation and respiration simultaneously...

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..Circadian control of trehalose synthase suggests a link between clock control of stress responses and that of development...

..These ccgs accumulate mRNA rhythmically with a circadian period in a frq-null strain, confirming the existence of a second oscillator in N. crassa...

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..Genome analysis suggests that RIP has had a profound impact on genome evolution, greatly slowing the creation of new genes through genomic duplication and resulting in a genome with an unusually low proportion of closely related genes...

..Together, our data indicate the existence of an Aspergillus circadian clock, which has properties that differ from that of the well-described clock of N. crassa...

..The group of unshared genes includes potential new targets for antifungals as well as loci implicated in human and plant physiology and disease...

..Our studies will have a significant impact on understanding how circadian clocks control overt rhythmicity and will potentially provide novel approaches for therapies for human diseases that result from circadian dysfunction. ..

..Together, these experiments will permit a more detailed understanding of how the cell is organized as a function of time. ..

..Understanding how the clock regulates the p38 pathway will facilitate efforts for developing new therapies for treating human diseases that result from clock dysfunction and/or misregulation of the p38 MAPK pathway. ..