Schwarz, J., & Bringmann, H.


Max Planck Institute for Biophysical Chemistry; Göttingen, Germany.

Application Area


Calcium Imaging


Sleep is characterized by reduced muscle activity resulting in reduced movement and a typical posture compatible with relaxed muscles. Prior to each molt, C. elegans larvae go through a phase of behavioral quiescence called Lethargus. Lethargus has sleep-like properties, but a specific posture has not yet been described. Do C. elegans larvae relax their muscles during sleep and do they assume a typical posture? We measured worm posture and body wall muscle activity using calcium imaging across the sleep-wake-like cycle. We found that worms were less curved and had less muscle activity during the sleep-like state. We conclude that during Lethargus, muscle activity is reduced, resulting in a relaxed body posture typical for a sleep-like state.


… “For fluorescence microscopy, samples were illuminated with LED (490nm, CoolLED) and imaged with standard light filters (Chroma or Semrock).”…

Product Associated Features

pE-100: A range of compact, simple-to-use, single wavelength illumination systems for screening fluorescence.

Product Type



PloS one

Year of Publication


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