Light and temperature are 2 of the most important environmental influences on all circadian clocks, and Neurospora provides an excellent system for understanding their effects. Progress made in the past decade has led to a basic molecular understanding of how the Neurospora clock works and how environmental factors influence it. The purpose of this review is to summarize what we currently know about the molecular mechanism of light and temperature entrainment in Neurospora.
References
1.
Aronson B, Johnson K, Loros JJ, and Dunlap JC (1994) Negative feedback defining a circadian clock: Autoregulation in the clock gene frequency. Science263:1578-1584.
2.
Ballario P, Talora C, Galli D, Linden H, and Macino G (1998) Roles in dimerization and blue light photoresponses of PAS and LOV domains of Neurospora crassa white collar proteins. Mol Micro29:719-729.
3.
Ballario P, Vittorioso P, Magrelli A, Talora C, Cabibbo A, and Macino G (1996) White collar-1, a central regulator of blue-light responses in Neurospora crassa, is a zinc-finger protein. EMBO J15:1650-1657.
4.
Briggs WR and Huala E (1999) Blue-light photoreceptors in higher plants. Annu Rev Cell Dev Biol15:33-62.
5.
Cheng P, He Q, Yang Y, Wang L, and Liu Y (2003) Functional conservation of light, oxygen, or voltage domains in light sensing. Proc Natl Acad Sci U S A. Forthcoming.
6.
Cheng P, Yang Y, Gardner KH, and Liu Y (2002) PAS domain-mediated WC-1/WC-2 interaction is essential for maintaining the steady state level of WC-1 and the function of both proteins in circadian clock and light responses of Neurospora. Mol Cell Biol22:517-524.
7.
Cheng P, Yang Y, Heintzen C, and Liu Y (2001a) Coiled-coil domain mediated FRQ-FRQ interaction is essential for its circadian clock function in Neurospora. EMBO J20:101-108.
8.
Cheng P, Yang Y, and Liu Y (2001b) Interlocked feedback loops contribute to the robustness of the Neurospora circadian clock. Proc Natl Acad Sci U S A98:7408-7413.
9.
Cheng P, Yang Y, Wang L, He Q, and Liu Y (2003) WHITE COLLAR-1, a multifunctional Neurospora protein involved in the circadian feedback loops, light sensing, and transcription repression of wc-2. J Biol Chem278:3801-3808.
10.
Christie JM, Salomon M, Nozue K, Wada M, and Briggs WR (1999) LOV (light, oxygen, or voltage) domains of the blue-light photoreceptor phototropin (nph1): Binding sites for the chromophore flavin mononucleotide. Proc Natl Acad Sci U S A96:8779-8783.
11.
Collett MA, Garceau N, Dunlap JC, and Loros JJ (2002) Light and clock expression of the Neurospora clock gene frequency is differentially driven by but dependent on WHITE COLLAR-2. Genetics160:149-158.
12.
Crosson S and Moffat K (2001) Structure of a flavin-binding plant photoreceptor domain: Insights into light-mediated signal transduction. Proc Natl Acad Sci U S A98:2995-3000.
13.
Crosthwaite SK, Dunlap JC, and Loros JJ (1997) Neurospora wc-1 and wc-2: Transcription, photoresponses, and the origins of circadian rhythmicity. Science276:763-769.
14.
Crosthwaite SK, Loros JJ, and Dunlap JC (1995) Light-induced resetting of a circadian clock is mediated by a rapid increase in frequency transcript. Cell81:1003-1012.
15.
Degli Innocenti F and Russo VEA (1984) Genetic analysis of blue light-induced responses in Neurospora crassa. In: Blue Light Effects in Biological Systems, H Senger, ed, pp 213-219, Springer-Verlag, Berlin.
16.
Denault DL, Loros JJ, and Dunlap JC (2001) WC-2 mediates WC-1-FRQ interaction within the PAS protein-linked circadian feedback loop of Neurospora. EMBO J20:109-117.
17.
Devlin PF and Kay SA (2001) Circadian photoperception. Annu Rev Physiol63:677-694.
18.
Dharmananda S (1980) Studies of the circadian clock of Neurospora crassa: Light-induced phase shifting [dissertation]. Santa Cruz: University of California.
19.
Dragovic Z, Tan Y, Gorl M, Roenneberg T, and Merrow M (2002) Light reception and circadian behavior in “blind” and “clock-less” mutants of Neurospora crassa. EMBO J21:3643-3651.
20.
Dunlap JC (1999) Molecular bases for circadian clocks. Cell96:271-290.
21.
Francis C and Sargent ML (1979) Effects of temperature perturbations on circadian conidiation in Neurospora. Plant Physiol64:1000-1009.
22.
Froehlich AC, Liu Y, Loros JJ, and Dunlap JC (2002) White Collar-1, a circadian blue light photoreceptor, binding to the frequency promoter. Science297:815-819.
23.
Garceau N, Liu Y, Loros JJ, and Dunlap JC (1997) Alternative initiation of translation and time-specific phosphorylation yield multiple forms of the essential clock protein FREQUENCY. Cell89:469-476.
24.
Glossop NR, Lyons LC, and Hardin PE (1999) Interlocked feedback loops within the Drosophila circadian oscillator. Science286:766-768.
25.
Gooch VD, Wehseler RA, and Gross CG (1994) Temperature effects on the resetting of the phase of the Neurospora circadian rhythm. J Biol Rhythms9:83-94.
26.
Gorl M, Merrow M, Huttner B, Johnson J, Roenneberg T, and Brunner M (2001) A PEST-like element in FREQUENCY determines the length of the circadian period in Neurospora crassa. EMBO J20:7074-7084.
27.
Harding RW and Shropshire WJ (1980) Photocontrol of carotenoid biosynthesis. Ann Rev Plant Physiol31:217-238.
28.
He Q, Cheng P, Yang Y, Wang L, Gardner KH, and Liu Y (2002) White collar-1, a DNA binding transcription factor and a light sensor. Science297:840-843.
29.
Heintzen C, Loros LL, and Dunlap JC (2001) The PAS protein VIVID defines a clock-associated feedback loop that represses light input, modulates gating and regulates clock resetting. Cell104:453-464.
30.
Johnson CH (2001) Endogenous timekeepers in photosynthetic organisms. Annu Rev Physiol63:695-728.
31.
Lakin-Thomas PL and Brody S (2000) Circadian rhythms in Neurospora crassa: Lipid deficiencies restore robust rhythmicity to null frequency and white-collar mutants. Proc Natl Acad Sci U S A97:256-261.
32.
Lakin-Thomas P, Coté G, and Brody S (1990) Circadian rhythms in Neurospora: Biochemistry and genetics. Crit Rev Micro17:365-416.
33.
Lee K, Dunlap JC, and Loros JJ (2003) Roles for WHITE COLLAR-1 in circadian and general photoperception in Neurospora crassa. Genetics163:103-114.
34.
Lee K, Loros JJ, and Dunlap JC (2000) Interconnected feedback loops in the Neurospora circadian system. Science289:107-110.
35.
Lewis ZA, Correa A, Schwerdtfeger C, Link KL, Xie X, Gomer RH, Thomas T, Ebbole DJ, 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 Microbiol45:917-931.
36.
Linden H, Ballario P, and Macino G (1997) Blue light regulation in Neurospora crassa. Fungal Genet Biol22:141-150.
37.
Linden H and Macino G (1997) White collar-2, a partner in blue-light signal transduction, controlling expression of light-regulated genes in Neurospora crassa. EMBO J16:98-109.
38.
Linden H, Rodriguez-Franco M, and Macino G (1997) Mutants of Neurospora crassa defective in regulation of blue light perception. Mol Gen Genet254:111-118.
39.
Liu Y, Garceau N, Loros JJ, and Dunlap JC (1997) Thermally regulated translational control mediates an aspect of temperature compensation in the Neurospora circadian clock. Cell89:477-486.
40.
Liu Y, Loros J, and Dunlap JC (2000) Phosphorylation of the Neurospora clock protein FREQUENCY determines its degradation rate and strongly influences the period length of the circadian clock. Proc Natl Acad Sci U S A97:234-239.
41.
Liu Y, Merrow MM, Loros JJ, and Dunlap JC (1998) How temperature changes reset a circadian oscillator. Science281:825-829.
42.
Loros JJ and Dunlap JC (2001) Genetic and molecular analysis of circadian rhythms in NEUROSPORA. Annu Rev Physiol63:757-794.
43.
Merrow M, Brunner M, and Roenneberg T (1999) Assignment of circadian function for the Neurospora clock gene frequency. Nature399:584-586.
44.
Merrow M, Franchi L, Dragovic Z, Gorl M, Johnson J, Brunner M, Macino G, and Roenneberg T (2001) Circadian regulation of the light input pathway in Neurospora crassa. EMBO J20:307-315.
45.
Nelson DC, Lasswell J, Rogg LE, Cohen MA, and Bartel B (2000) FKF1, a clock-controlled gene that regulates the transition to flowering in Arabidopsis. Cell101:331-340.
46.
Paietta J and Sargent M (1981) Photoreception in Neurospora crassa: Correlation of reduced light sensitivity with flavin deficiency. Proc Nat Acad Sci U S A78:5573-5577.
47.
Reppert SM and Weaver DR (2001) Molecular analysis of mammalian circadian rhythms. Annu Rev Physiol63:647-676.
48.
Salomon M, Christie JM, Knieb E, Lempert U, and Briggs WR (2000) Photochemical and mutational analysis of the FMN-binding domains of the plant blue light receptor, phototropin. Biochemistry39:9401-9410.
49.
Sancar A (2000) Cryptochrome: The second photoactive pigment in the eye and its role in circadian photoreception. Annu Rev Biochem69:31-67.
50.
Sargent ML and Briggs WR (1967) The effect of light on a circadian rhythm of conidiation in Neurospora. Plant Physiol42:1504-1510.
51.
Schultz TF, Kiyosue T, Yanovsky M, Wada M, and Kay SA (2001) A role for LKP2 in the circadian clock of Arabidopsis. Plant Cell13:2659-2670.
52.
Schwerdtfeger C and Linden H (2000) Localization and light-dependent phosphorylation of white collar 1 and 2, the two central components of blue light signaling in Neurospora crassa. Eur J Biochem267:414-422.
53.
Schwerdtfeger C and Linden H (2001) Blue light adaptation and desensitization of light signal transduction in Neurospora crassa. Mol Microbiol39:1080-1087.
54.
Shearman LP, Sriram S, Weaver DR, Maywood ES, Chaves I, Zheng B, Kume K, Lee CC, van der Horst GT, Hastings MH, et al. (2000) Interacting molecular loops in the mammalian circadian clock. Science288:1013-1019.
55.
Shrode LB, Lewis ZA, White LD, Bell-Pedersen D, and Ebbole DJ (2001) vvd is required for light adaptation of conidiation-specific genes of Neurospora crassa, but not circadian conidiation. Fungal Genet Biol32:169-181.
56.
Somers DE, Schultz TF, Milnamow M, and Kay SA (2000) ZEITLUPE encodes a novel clock-associated PAS protein from Arabidopsis. Cell101:319-328.
57.
Steinlechner S, Jacobmeier B, Scherbarth F, Dernbach H, Kruse F, and Albrech U (2002) Robust circadian rhythmicity of Per1 and Per2 mutant mice in constant light, and dynamics of Per1 and Per2 gene expression under long and short photoperiods. J Biol Rhythms17:202-209.
58.
Talora C, Franchi L, Linden H, Ballario P, and Macino G (1999) Role of a white collar-1-white collar-2 complex in blue-light signal transduction. EMBO J18:4961-4968.
59.
Yang Y, Cheng P, and Liu Y (2002) Regulation of the Neurospora circadian clock by casein kinase II. Genes & Dev16:994-1006.
60.
Yang Y, Cheng P, Zhi G, and Liu Y (2001) Identification of a calcium/calmodulin-dependent protein kinase that phosphorylates the Neurospora circadian clock protein FREQUENCY. J Biol Chem276:41064-41072.
61.
Young MW (1998) The molecular control of circadian behavioral rhythms and their entrainment in Drosophila. Annu Rev Biochem67:135-152.
62.
Young MW and Kay SA (2001) Time zones: A comparative genetics of circadian clocks. Nat Rev Genet2:702-715.
