Characterization of a Vivid Homolog in Botrytis cinerea.

Blue light-signaling pathways regulated by members of the light-oxygen-voltage (LOV) domain family integrate stress responses, circadian rhythms and pathogenesis in fungi. The canonical signaling mechanism involves two LOV-containing proteins that maintain homology to Neurospora crassa Vivid (NcVVD) and White Collar 1 (NcWC1). These proteins engage in homo- and heterodimerization events that modulate gene transcription in response to light. Here, we clone and characterize the VVD homolog in Botrytis cinerea (BcVVD). BcVVD retains divergent photocycle kinetics and is incapable of LOV mediated homodimerization, indicating modification of the classical hetero/homodimerization mechanism of photoadaptation in fungi.