Premium
Genetic dissection of ion currents underlying all‐or‐none action potentials in C. elegans body‐wall muscle cells
Author(s) -
Liu Ping,
Ge Qian,
Chen Bojun,
Salkoff Lawrence,
Kotlikoff Michael I.,
Wang ZhaoWen
Publication year - 2011
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1113/jphysiol.2010.200683
Subject(s) - ryanodine receptor , ion channel , endoplasmic reticulum , biology , skeletal muscle , myocyte , caenorhabditis elegans , membrane potential , microbiology and biotechnology , potassium channel , biophysics , intracellular , chemistry , anatomy , biochemistry , receptor , gene
Non‐technical summary Mammalian skeletal muscle contractions are initiated by all‐or‐none action potentials (APs) triggered by motoneurons. In C. elegans locomotory muscle, however, the characteristics of APs, the underlying ion channels, and their role in Ca 2+ release are poorly understood. Here we show that C. elegans locomotory muscle fires spontaneous, all‐or‐none APs, which appear to be modulated by motoneuron activity. The upstroke of muscle APs requires Ca 2+ entry through a voltage‐gated Ca 2+ channel (EGL‐19), whereas the downstroke of the APs relies on a voltage‐gated potassium channel as well as a Ca 2+ ‐ and Cl − ‐activated potassium channel. AP‐elicited elevations of intracellular Ca 2+ concentration require both EGL‐19 in the plasma membrane and the ryanodine receptor in the sarcoplasmic reticulum membrane. The discovery of all‐or‐none action potentials in C. elegans body‐wall muscle brings the physiology of C. elegans much closer to that of other metazoans, and strengthens its utility as a model organism.