Abstract
Aspergillus nidulans responds to light in several aspects. The balance between sexual and asexual development as well as the amount of secondary metabolites produced is controlled by light. Here, we show that germination is largely delayed by blue (450 nm), red (700 nm), and far-red light (740 nm). The largest effect was observed with far-red light. Whereas 60 % of the conidia produced a germ tube after 20 h in the dark, less than 5 % of the conidia germinated under far-red light conditions. Because swelling of conidia was not affected, light appears to act at the stage of germ-tube formation. In the absence of nutrients, far-red light even inhibited swelling of conidia, whereas in the dark, conidia did swell and germinated after prolonged incubation. The blue-light signaling components, LreA (WC-1) and LreB (WC-2), and also the cryptochrome/photolyase CryA were not required for germination inhibition. However, in the phytochrome mutant, ∆fphA, the germination delay was released, but germination was delayed in the dark in comparison to wild type. This suggests a novel function of phytochrome as far-red light sensor and as activator of polarized growth in the dark.
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References
Abad A, Fernández-Molina JV, Bikandi J, Ramírez A, Margbareto J, Sendino J, Hernando FL, Pontón J, Garaizar J, Rementeria A (2010) What makes Aspergillus fumigatus a successful pathogen? Genes and molecules involved in invasive aspergillosis. Rev Iberoam Micol 27:155–182
Adams TH (1994) Asexual sporulation in higher fungi. In: Gow NAR, Gadd GM (eds) The growing fungus. Chapman and Hall, London, pp 367–382
Baker CL, Loros JJ, Dunlap JC (2011) The circadian clock of Neurospora crassa. FEMS Microbiol Rev 36(1):95–110
Ballario P, Vittorioso P, Margrelli A, Toalora C, Cabibo A, Macino G (1996) White collar-1, a central regulator of blue light responses in Neurospora crassa, is a zinc finger protein. EMBO J 15:1650–1657
Bayram Ö, Braus GH (2012) Coordination of secondary metabolism and development in fungi: the velvet family of regulatory proteins. FEMS Microbio Rev 36:1–24
Bayram Ö, Biesemann C, Krappmann S, Galland P, Braus GH (2008a) More than a repair enzyme: Aspergillus nidulans photolyase-like CryA is a regulator of sexual development. Mol Biol Cell 19:3254–3262
Bayram O, Krappmann S, Ni M, Bok JW, Helmstaedt K, Valerius O, Braus-Stromeyer S, Kwon NJ, Keller NP, Yu JH, Braus GH (2008b) VelB/VeA/LaeA complex coordinates light signal with fungal development and secondary metabolism. Science 320:1504–1506
Blumenstein A, Vienken K, Tasler R, Purschwitz J, Veith D, Frankenberg-Dinkel N, Fischer R (2005) The Aspergillus nidulans phytochrome FphA represses sexual development in red light. Curr Biol 15:1833–1838
Bragg JD (1981) Inhibitory effects of light on ascospore germination of Pseudoarachniotus marginosporus. Mycologia 73:681–688
Brandt S, von Stetten D, Bünther M, Hildebrandt P, Frankenberg-Dinkel N (2008) The fungal phytochrome FphA from Aspergillus nidulans. J Biol Chem 283:34605–34614
Brown LS, Dioumaev AK, Lanyi JK, Spudich EN, Spudich JL (2001) Photochemical reaction cycle and proton transfer in Neurospora rhodopsin. J Biol Chem 276:32495–32505
Brunner M, Simons MJ, Merrow M (2008) Lego clocks: building a clock from parts. Genes Dev 22:1422–1426
Busch S, Braus GH (2007) How to build a fungal fruit body: from uniform cells to specialized tissue. Mol Microbiol 64:873–876
Calvo AM (2008) The VeA regulatory system and its role in morphological and chemical development in fungi. Fungal Genet Biol 45:1053–1061
Degli-Innocenti F, Chambers JA, Russo VE (1984) Conidia induce the formation of protoperithecia in Neurospora crassa: further characterization of white collar mutants. J Bacteriol 159:808–810
d’Enfert C (1997) Fungal spore germination: insights from the molecular genetics of Aspergillus nidulans and Neurospora crassa. Fungal Genet Biol 21:163–172
Froehlich AC, Liu Y, Loros JJ, Dunlap JC (2002) White collar-1, a circadian blue light photoreceptor, binding to the frequency promoter. Science 297:815–819
Harispe L, Portela C, Scazzocchio C, Peñalva MA, Gorfinkiel L (2008) Ras GTPase-activating protein regulation of actin cytoskeleton and hyphal polarity in Aspergillus nidulans. Eukaryot Cell 7:141–153
Hatakeyama R, Nakahama T, Higuchi Y, Kitamoto K (2007) Light represses conidiation in koji mold Aspergillus oryzae. Biosci Biotech Biochem 71:1844–1849
Heintzen C, Liu Y (2007) The Neurospora crassa circadian clock. Adv Genet 58:25–66
Idnurm A, Verma S, Corrochano LM (2010) A glimpse into the basis of vision in the kingdom Mycota. Fungal Genet Biol 47:881–892
Käfer E (1965) The origin of translocations in Aspergillus nidulans. Genetics 52:217–232
Käfer E (1977) Meiotic and mitotic recombination in Aspergillus and its chromosomal aberrations. Adv Genet 19:33–131
Kim H-S, Han K-Y, Kim K-J, Han D-M, Jahng K-Y, Chae K-S (2002) The veA gene activates sexual development in Aspergillus nidulans. Fungal Genet Biol 37:72–80
Lucas JA, Kendrick RE, Givan CV (1975) Photocontrol of fungal spore germination. Plant Physiol 56:847–849
Lukens RJ (1965) Reversal by red light of blue light inhibition of sporulation in Alternaria solani. Phytophathology 55:1032
Mooney JL, Yager LN (1990) Light is required for conidiation in Aspergillus nidulans. Genes Dev 4:1473–1482
Nelson MA, Morelli G, Carattoli A, Romano N, Macino P (1989) Molecular cloning of a Neurospora crassa carotenoid biosythetic gene (albin-3) regulated by blue light and the products of the white collar genes. Mol Cell Biol 9:1271–1276
Osherov N, May G (2000) Conidial germination in Aspergillus nidulans requires RAS signaling and protein synthesis. Genetics 155:647–656
Osherov N, May GS (2001) The molecular mechanisms of conidial germination. FEMS Microbiol Lett 199:153–160
Purschwitz J, Müller S, Kastner C, Fischer R (2006) Seeing the rainbow: light sensing in fungi. Curr Opin Microbiol 9:566–571
Purschwitz J, Müller S, Kastner C, Schöser M, Haas H, Espeso EA, Atoui A, Calvo AM, Fischer R (2008) Functional and physical interaction of blue and red-light sensors in Aspergillus nidulans. Curr Biol 18:255–259
Purschwitz J, Müller S, Fischer R (2009) Mapping the interaction sites of Aspergillus nidulans phytochrome FphA with the global regulator VeA and the white collar protein LreB. Mol Genet Genomics 281:35–42
Rodriguez-Romero J, Hedtke M, Kastner C, Müller S, Fischer R (2010) Fungi, hidden in soil or up in the air: light makes a difference. Annu Rev Microbiol (64):585–610
Stinnett SM, Espeso EA, Cobeno L, Araujo-Bazan L, Calvo AM (2007) Aspergillus nidulans VeA subcellular localization is dependent on the importin alpha carrier and on light. Mol Microbiol 63:242–255
Talora C, Franchi L, Linden H, Ballario P, Macino G (1999) Role of a white collar-1-white collar-2 complex in blue-light signal transduction. EMBO J 18:4961–4968
Tasler R, Moises T, Frankenberg-Dinkel N (2005) Biochemical and spectroscopic characterization of the bacterial phytochrome of Pseudomonas aeruginosa. FEBS J 272:1927–1936
Waring RB, May GS, Morris NR (1989) Characterization of an inducible expression system in Aspergillus nidulans using alcA and tubulin coding genes. Gene 79:119–130
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This work was supported by the Deutsche Forschungsgemeinschaft (DFG) and the Baden-Württemberg Stiftung.
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Communicated by U. Kueck.
J. Röhrig and C. Kastner contributed equally.
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Röhrig, J., Kastner, C. & Fischer, R. Light inhibits spore germination through phytochrome in Aspergillus nidulans . Curr Genet 59, 55–62 (2013). https://doi.org/10.1007/s00294-013-0387-9
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DOI: https://doi.org/10.1007/s00294-013-0387-9