from Maria Olmedo, Carmen Cuger-Herreros and Luis M. Corrochano writing in Neurospora: Genomics and Molecular Biology:
Fungi use light cues to acquire environmental information like day length throughout the year. Neurospora adapts its development and behaviour to the changing conditions of the environment using light as a signal for the regulation of gene transcription. Neurospora perceives light through the blue light photoreceptor WHITE COLLAR-1 (WC-1). WC-1 dimerizes with WC-2 to form the White Collar Complex (WCC) that activates the transcription of target genes by binding to Light Regulated Elements (LRE) in their promoters. The light-dependent accumulation of certain proteins is responsible for light responses. Light activates genes involved in a variety of processes including development of asexual spores and sexual structures, biosynthesis of photo-protective pigments, and entrainment of the circadian clock. However, the activation of gene transcription by light is transient. After extended illumination, the light-induced transcription ceases and further incubation in the dark is required before transcription in response to light is again activated. This feature, photoadaptation, depends on the blue-light photoreceptor VIVID (VVD). This chapter will present the mechanisms of light perception and regulation of gene expression that lead to light responses in Neurospora.
Further reading: Neurospora: Genomics and Molecular Biology