Seeing the rainbow: light sensing in fungi.
Light is essential for photosynthetic organisms, but also serves as an important environmental cue for non-photosynthetic species; thus, light sensing is evolutionarily conserved throughout the kingdoms, from archaea and fungi to humans. Light sensors are chromoproteins, the low-molecular weight compound of which absorbs specific wavelengths and induces a reaction from the protein. In fungi, three light-sensing systems have been described at the molecular level. Blue-light sensing is achieved by a flavin-based photoreceptor, which itself acts as a transcription factor, and red-light sensing is achieved by a phytochrome, a molecule until recently thought to be confined to plants. A retinal-based opsin-system was discovered recently, although a biological function remains to be determined. The challenge for future research will be the identification of further components of signalling cascades, the identification of light-regulated genes and the unravelling of possible functional interplays between the different light control systems.
Purschwitz
Janina
J
Max-Planck-Institute for terrestrial Microbiology, Department of Applied Microbiology, University of Karlsruhe Institute for Applied Biosciences, Hertzstrasse 16, D-76187 Karlsruhe, Germany.
Müller
Sylvia
S
Kastner
Christian
C
Fischer
Reinhard
R
D005658:Fungi / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D015966:Gene Expression Regulation, Fungal; D010786:Photoreceptor Cells / Q000378:metabolism* / Q000502:physiology; D010834:Phytochrome / Q000235:genetics / Q000378:metabolism*; D017299:Rod Opsins / Q000378:metabolism
D017299:Rod Opsins; D010834:Phytochrome