This event will be in-person only to Columbia University Affiliates and will not offer a Zoom option

Gáspár Jékely, PhD

Professor, Department of Evolutionary Neuroscience, Centre for Organismal Studies

Heidelberg University

Neuronal mechanism of hydrostatic pressure sensation in zooplankton

Hydrostatic pressure is a dominant environmental cue for vertically migrating marine organisms but the physiological mechanisms of responding to pressure changes remain unclear. We uncovered the cellular and circuit bases of a barokinetic response in the planktonic larva of the marine annelid Platynereis dumerilii. Increases in pressure induced a rapid, graded and adapting upward swimming response due to faster ciliary beating. By calcium imaging, we found that brain ciliary photoreceptors showed a graded response to pressure changes. The photoreceptors in animals mutant for ciliary opsin-1 had a smaller ciliary compartment and mutant larvae showed diminished pressure responses. The ciliary photoreceptors synaptically connect to the head multiciliary band that propels swimming via serotonergic motoneurons. Genetic inhibition of the serotonergic cells blocked pressure-dependent increases in ciliary beating. We conclude that ciliary photoreceptors function as pressure sensors and activate ciliary beating through serotonergic signalling during barokinesis.

Relevant Publications:

A ciliary photoreceptor-cell circuit mediates pressure response in marine zooplankton

Nitric oxide feedback to ciliary photoreceptor cells gates a UV avoidance circuit

Host(s): Maria Antonietta Tosches (Faculty)

Please contact [email protected] with any questions.

The Columbia Neuroscience Seminar series is a collaborative effort of Columbia's Zuckerman Institute, the Department of Neuroscience, the Doctoral Program in Neurobiology and Behavior and the Columbia Translational Neuroscience Initiative, and with support from the Kavli Institute for Brain Science.