Linked Life Data

11745661

Source:http://linkedlifedata.com/resource/pubmed/id/11745661

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-12-17
pubmed:abstractText
More than fifty FMRFamide-like neuropeptides have been identified in nematodes. We addressed the role of a subset of these in the control of nematode feeding by electrophysiological recording of the activity of C. elegans pharynx. AF1 (KNEFIRFamide), AF2 (KHEYLRFamide), AF8 (KSAYMRFamide), and GAKFIRFamide (encoded by the C. elegans genes flp-8, flp-14, flp-6, and flp-5, respectively) increased pharyngeal action potential frequency, in a manner similar to 5-HT. In contrast, SDPNFLRFamide, SADPNFLRFamide, SAEPFGTMRFamide, KPSVRFamide, APEASPFIRFamide, and AQTVRFamide (encoded by the C. elegans genes flp-1; flp-1; flp-3; flp-9; flp-13, and flp-16, respectively) inhibited the pharynx in a manner similar to octopamine. Only three of the neuropeptides had potent effects at low nanomolar concentrations, consistent with a physiological role in pharyngeal regulation. Therefore, we assessed whether these three peptides mediated their actions either directly on the pharynx or indirectly via the neural circuit controlling its activity by comparing actions between wild-type and mutants with deficits in synaptic signaling. Our data support the conclusion that AF1 and SAEPFGTMRFamide regulate the activity of the pharynx indirectly, whereas APEASPFIRFamide exerts its action directly. These results are in agreement with the expression pattern for the genes encoding the neuropeptides (Kim and Li, 1999) as both flp-8 and flp-3 are expressed in extrapharyngeal neurons, whereas flp-13 is expressed in I5, a neuron with synaptic output to the pharyngeal muscle. These results provide the first, direct, functional information on the action of neuropeptides in C. elegans. Furthermore, we provide evidence for a putative inhibitory peptidergic synapse, which is likely to have a role in the control of feeding.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-3034
pubmed:author
pubmed:copyrightInfo
Copyright 2001 John Wiley & Sons, Inc.
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
235-44
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Regulation of the pharynx of Caenorhabditis elegans by 5-HT, octopamine, and FMRFamide-like neuropeptides.
pubmed:affiliation
Centre for Neuroscience, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton S016 7PX, United Kingdom.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't