vvd is required for light adaptation of conidiation-specific genes of Neurospora crassa, but not circadian conidiation

Shrode, L. B., Lewis, Z. A., White, L. D., Bell-Pedersen, D., and Ebbole, D . J. 2001. vvd is required for light adaptation of conidiation-specific gen es of Neurospora crassa, but not circadian conidiation. Fungal Genetics and Biology 32, 169-181. con-10 and con-6 are two of the conidiation (con) gen es of Neurospora crassa that were identified based on their preferential ex pression during macroconidiophore development. They are also regulated by s everal other environmental stimuli independent of development, including a transient induction by light. We identified an allele of vivid (vvd) in a m utant screen designed to obtain strains with altered expression of con-10. vvd mutants display enhanced carotenoid pigmentation in response to light. In addition, con-10 and con-6 show a heightened response to photoinduction. We tested the function of the light-responsive circadian clock in the vvd mutant and found no major defect in the circadian rhythm of conidiation or light regulation of a key clock component, frequency (frq). We conclude tha t vvd is primarily involved in a process of light-dependent gene repression , called light adaptation. Although a number of gene products are known to control light induction in fungi, vvd is the first gene shown to have a rol e in adaptation to constant light. (C) 2001 Academic Press.