Abstract

Circadian clocks confer close to 24-hour rhythms to a large number of processes in most organisms across different evolutionary lineages. These endogenous cellular timekeepers regulate rhythms in gene expression, physiology and behaviour and enable organisms to anticipate predictable environmental variations. Studies conducted in the ascomycete Neurospora crassa have been instrumental in unveiling the molecular and genetic basis of the emergent property of time-telling. The Neurospora circadian system integrates a series of cellular processes, including light perception, phosphorylation and dephosphorylation dynamics, nuclear trafficking, signal transduction pathways, chromatin remodelling and transcriptional regulation among others, that give rise to a robust pacemaker capable of coordinating rhythmic control of several aspects of Neurospora biology, the most obvious one being the daily appearance of asexual spores. This chapter will provide an overview of the major advances in the field, with an emphasis on the later discoveries propelled by the release of the Neurospora genome and the adoption of functional genomic strategies. In addition, the state of the art in the studies of the Neurospora circadian system will be discussed, along with the main challenges and opportunities ahead.