Rhythmic Conidiation in Neurospora crassa

  • Cas Kramer
Part of the Methods in Molecular Biology™ book series (MIMB, volume 362)


In the filamentous fungus Neurospora crassa the production of asexual spores (conidia) is regulated by its circadian clock. When the fungus is grown on a thin layer of agar medium in long growth tubes (so-called “race tubes”), restricting its growth to one direction only, bright orange bands are clearly visible. This banding pattern persists with a periodicity of approx 24 h in the absence of any environmental stimuli. The bands are formed by alternating zones of nonsporulating mycelium and mycelium laden with orange conidia. Assaying Neurospora conidiation on race tubes is a simple yet powerful and versatile tool for studying the circadian clock of this model organism.

Key Words

Circadian conidia asexual sporulation filamentous fungus bread mold race tube aerial hyphae mycelium free-run entrainment phase response curve Chrono 


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Copyright information

© Humana Press Inc. 2007

Authors and Affiliations

  • Cas Kramer
    • 1
  1. 1.Department of GeneticsUniversity of LeicesterUK

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