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Electrophysiology of the rhythmic defecation program in nematode Heterorhabditis megidis.

ABSTRACT: The nervous system controls most rhythmic behaviors, with a remarkable exception. In Caenorhabditis elegans periodic defecation rhythm does not appear to involve the nervous system. Such oscillations are studied in detail with genetic and molecular biology tools. The small size of C. elegans cells impairs the use of standard electrophysiological methods. We studied a similar rhythmic pacemaker in the noticeably larger gut cells of Heterorhabditis megidis nematode. H. megidis defecation cycle is driven by a central pattern generator (CPG) associated with unusual all-or-none hyper-polarization "action potential". The CPG cycle period depends on the membrane potential and CPG cycling also persisted in experiments where the membrane potential of gut cells was continuously clamped at steady voltage levels. The usual excitable tissue description does not include the endoderm or imply the generation of hyper-polarization spikes. The nematode gut cells activity calls for a reevaluation of the excitable cells definition.

SUBMITTER: Kuznetsov VP

PROVIDER: S-EPMC5736584 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Electrophysiology of the rhythmic defecation program in nematode Heterorhabditis megidis.

Kuznetsov Victor P VP Slivko-Koltchik Georgy A GA Voronov Dmitry A DA Panchin Yuri V YV

Scientific reports 20171219 1

The nervous system controls most rhythmic behaviors, with a remarkable exception. In Caenorhabditis elegans periodic defecation rhythm does not appear to involve the nervous system. Such oscillations are studied in detail with genetic and molecular biology tools. The small size of C. elegans cells impairs the use of standard electrophysiological methods. We studied a similar rhythmic pacemaker in the noticeably larger gut cells of Heterorhabditis megidis nematode. H. megidis defecation cycle is ...[more]

PMID: 29259280

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Dataset Information

Electrophysiology of the rhythmic defecation program in nematode Heterorhabditis megidis.

Publications

Electrophysiology of the rhythmic defecation program in nematode Heterorhabditis megidis.

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