title: Circadian control sheds light on fungal bioluminescence.
abstract: Bioluminescence, the creation and emission of light by organisms, affords insight into the lives of organisms doing it. Luminous living things are widespread and access diverse mechanisms to generate and control luminescence [1-5]. Among the least studied bioluminescent organisms are phylogenetically rare fungi-only 71 species, all within the ∼ 9,000 fungi of the temperate and tropical Agaricales order-are reported from among ∼ 100,000 described fungal species [6, 7]. All require oxygen [8] and energy (NADH or NADPH) for bioluminescence and are reported to emit green light (λmax 530 nm) continuously, implying a metabolic function for bioluminescence, perhaps as a byproduct of oxidative metabolism in lignin degradation. Here, however, we report that bioluminescence from the mycelium of Neonothopanus gardneri is controlled by a temperature-compensated circadian clock, the result of cycles in content/activity of the luciferase, reductase, and luciferin that comprise the luminescent system. Because regulation implies an adaptive function for bioluminescence, a controversial question for more than two millennia [8-15], we examined interactions between luminescent fungi and insects [16]. Prosthetic acrylic resin "mushrooms," internally illuminated by a green LED emitting light similar to the bioluminescence, attract staphilinid rove beetles (coleopterans), as well as hemipterans (true bugs), dipterans (flies), and hymenopterans (wasps and ants), at numbers far greater than dark control traps. Thus, circadian control may optimize energy use for when bioluminescence is most visible, attracting insects that can in turn help in spore dispersal, thereby benefitting fungi growing under the forest canopy, where wind flow is greatly reduced.
authors: Departamento de Oceanografia Física, Química, e Geológica, Instituto Oceanográfico, Universidade de São Paulo, São Paulo, SP 05508-120, Brazil.
authors: Anderson G
authors: AG
authors: Oliveira
authors: Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil. Electronic address: stevani@iq.usp.br.
authors: Cassius V
authors: CV
authors: Stevani
authors: Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil; Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP 05508-000, Brazil.
authors: Hans E
authors: HE
authors: Waldenmaier
authors: Departamento de Bioquímica, Universidade Federal de São Carlos, Campus Sorocoba, Rodovia João Leme dos Santos, km 110, Sorocaba, SP 18052-780, Brazil.
authors: Vadim
authors: V
authors: Viviani
authors: Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
authors: Jillian M
authors: JM
authors: Emerson
authors: Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA.
authors: Jennifer J
authors: JJ
authors: Loros
authors: Department of Genetics, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA. Electronic address: jay.c.dunlap@dartmouth.edu.
authors: Jay C
authors: JC
authors: Dunlap
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D005658:Fungi / Q000502:physiology*; D007313:Insecta; D008156:Luciferases / Q000378:metabolism; D049449:Luminescence; D008163:Luminescent Measurements / Q000379:methods; D010088:Oxidoreductases / Q000378:metabolism; D013696:Temperature
chemical_list: D010088:Oxidoreductases; D008156:Luciferases