3258 TAMU
College Station, TX 77843-3258

Office:
3258 TAMU
Biological Sciences Building West
Room 210A
979-847-9237

Lab:
Biological Sciences Building West
Room 208-210
979-847-9239

Fax: 979-845-2891
Email: dpedersen@mail.bio.tamu.edu

Most organisms possess an internal timing mechanism called the circadian clock that allows them to partition activities to appropriate times of the day and to keep in synchrony with natural environmental cycles. The circadian clock regulates many aspects of physiology, biochemistry, and behavior; thus, the impact of abnormalities in circadian timing on the general health and disease resistance of humanity is considerable, ranging from drug metabolism to sleep disorders, epilepsy and cancer. At the heart of the eukaryotic clock lie molecular oscillators that are made up of genes and proteins that form autoregulatory feedback loops. However, the mechanisms by which time information is transduced from the oscillators through output pathways to control rhythmicity are not well understood. We are addressing this question in the model fungus Neurospora crassa . Using DNA chip technology in wild type and clock-mutant strains, in combination with genetic screens and selections, we have identified several time-of-day signaling factors, and we have uncovered potentially novel circadian oscillators that regulate rhythmicity in a subset of genes. Critical questions that are now being addressed in N. crassa , and that are relevant to the organization of all clocks, including the human clock, are; what are the roles of multiple circadian oscillators in cells, and how do these oscillators communicate with each other to coordinately control rhythmicity?

Vitalini, M, dePaula, R, Goldsmith, C, Jones, C, Borkovich, K, and Bell-Pedersen, D (2007) Circadian rhythmicity mediated by temporal regulation of the activity of a p38 MAPK. Proc. Natl. Acad. Sci USA 104:18223-8.

dePaula, RM., Vitalini, MW, Gomer, RH, and Bell-Pedersen, D (2007) Complexity of the Neurospora crassa circadian clock system: Mulitple loops and oscillators. Cold Spring Harbor Symposia on Quantitative Biology: Clocks and Rhythms, Volume 72.

Beasley, AK, Lamb, TM, Versaw, WK, and Bell-Pedersen D. (2007) A ras-1bd Mauriceville strain for mapping mutations in Oak Ridge ras-1bd strains. Fungal Genetics Newsletter 54.

Vitalini, M., dePaula, R., Park, W.D., Bell-Pedersen, D. (2006) The rhythms of life: circadian output pathways in Neurospora. J Biol. Rhythms 21: 432-444.

Liu, Y. and Bell-Pedersen, D. (2006) Circadian rhythms in Neurospora and other filamentous fungi. Euk Cell. 5: 1184-1193.

de Paula, R., Lewis, Z.L., Greene, A.V., Seo, K.S., Vitalini, M., Morgan, L., Bennett, L., Gomer, R.H., and Bell-Pedersen, D. (2006) Two circadian timing circuits in Neurospora crassa cells share components and regulate distinct rhythmic processes. J. Biol. Rhythms 21:159-68.

Galagan, JE, Calvo SE, Cuomo C, Ma L-J, Wortman, J, Batzoglou S, Lee S-I, Bastürkmen M, Spevak CC, Clutterbuck J, Kapitonov V, Jurka J,Scazzocchio C, Farmam, M, Butler , J, Purcell S, Harris S, Braus GH, Draht O, Busch S, D'Enfert C, Bouchier , C, Goldman GH, Bell-Pedersen D, et al. (2005) Sequencing of Aspergillus nidulans and Comparative Analysis with A. fumigatus and A. oryzae Nature 438: 1105-1115.

Bell-Pedersen, D, Cassone, VM, Earnest, DJ, Golden SS, Hardin, PE, Thomas TL, Zoran, MJ (2005) Circadian rhythms from multiple oscillators: lessons from diverse organisms. Nat Rev Genet. 6:544-556.

Pregueiro AM, Price-Lloyd, N., Bell-Pedersen, D, Heintzen, C, Loros, JJ, Dunlap, JC (2005) Assignment of an essential role for the Neurospora frequency gene in circadian entrainment to temperature cycles. Proc. Natl. Acad. Sci, USA 102:2210-2215.

Xie X, Wilkinson HH, Correa A, Lewis ZA, Bell-Pedersen D, Ebbole DJ. (2004) Transcriptional response to glucose starvation and functional analysis of a glucose transporter of Neurospora crassa. Fungal Genet. Biol. 41:1104-1119.

Allen GC, Farnell Y, Bell-Pedersen D, Cassone VM, Earnest DJ.(2004) Effects of altered Clock gene expression on the pacemaker properties of SCN2.2 cells and oscillatory properties of NIH/3T3 cells. Neuroscience. 127: 989-999.

Vitalini, M., Morgan, L., March, I.J., and Bell-Pedersen, D. (2004) A genetic selection for circadian output pathway (cop) mutations in Neurospora crassa. Genetics. 167: 119-129 .

Correa, A. Lewis, Z.A, Greene, A.V., March I.J., and Bell-Pedersen, D. (2003) Microarray profiling reveals multiple oscillators regulate circadian gene expression in Neurospora. Proc. Natl. Acad. Sci. USA 100(23):13597-602.

Galagan, J., Calvo, S.E., Borkovich, K.. Selker, E., Read, N., FitzHugh W., Ma, L-M., Smirnov S., Purcell , S., Rehman , B, Elkins,T. Engels,R., Wang, S., Nielsen, C.B., Roy, A., Ianakiev, P., Davis, R., Nelson, MA, Werner-Washburne, M., Mewes, W., Kinsey, J., Braun, E., Zelter, A., Shulte U., Kothe, G., Jedd, G., Bell-Pedersen, D., et al. (2003) The Genome Sequence of the Filamentous Fungus Neurospora crassa Nature 422: 859-869.

Greene, A. V., Keller, N., Haas, H., and Bell-Pedersen, D. (2003) A circadian oscillator in Aspergillus spp. regulates daily development and gene expression Euk. Cell 2: 231-237.

Lewis, Z.A., Correa, A., Schwerdtfeger, C., Link, K., Xie, X., Gomer, R., Thomas,T., Ebbole, D. and Bell-Pedersen, D. (2002) Overexpression of WHITE COLLAR-1 (WC-1) activates circadian clock-associated genes, but is not sufficient to induce most light-regulated gene expression in Neurospora crassa . Mol. Micro 45: 917-931.

Bobrowicz, P. Pawlak, R., Correa, A., Bell-Pedersen,D., and Ebbole, D. (2002) The Neurospora crassa pheromone precursor genes are regulated by the mating type locus and the circadian clock. Mol. Micro. 45: 795-804.

Correa A., and Bell-Pedersen, D. (2002) Distinct signaling pathways from the circadian clock participate to regulate rhythmic conidiospore development in Neurospora crassa . Euk. Cell 1: 273-280.

Shrode, L., Lewis, Z.A., White, L.C., Bell-Pedersen, D., Ebbole, D.J. (2001) vvd is required for light adaptation of conidiation-specific genes of Neurospora crassa , but not circadian conidiation. Fungal Genet. Biol. 32: 169-181.

Bell-Pedersen, D., Lewis, Z.A., Loros, J.J., and Dunlap, J.C. (2001) The Neurospora circadian clock regulates a transcription factor that controls rhythmic expression of the output eas(ccg-2) gene. Mol. Micr. 41: 897-909.

Morgan, L. Feldman, J., and Bell-Pedersen, D. (2001) Genetic interactions between clock mutations in N. crassa : can they help us to understand complexity. Philos. Trans. R. Soc. Lond. 356: 1717-1724.