Circadian regulation of the light input pathway in Neurospora crassa

FREQUENCY (FRQ) is a critical element of the circadian system of Neurospora , The white collar genes are important both for light reception and circadi an function. We show that the responsiveness of the light input pathway is circadianly regulated. This circadian modulation extends to light-inducible components and functions that are not rhythmic themselves in constant cond itions. FRQ interacts genetically and physically with WHITE COLLAR-I, and p hysically with WHITE COLLAR-2. These findings begin to address how componen ts of the circadian system interact with basic cellular functions, in this case with sensory transduction.