title: The Caenorhabditis elegans homeobox gene ceh-19 is required for MC motorneuron function.
abstract: Simplicity has made C. elegans pharyngeal development a particularly well-studied subject. Nevertheless, here we add the previously uncharacterized homeobox gene F20D12.6/ceh-19 to the set of transcription factor genes involved. GFP reporter assays revealed that ceh-19 is expressed in three pairs of neurons, the pharyngeal pace-maker neurons MC, the amphid neurons ADF and the phasmid neurons PHA. ceh-19(tm452) mutants are viable and fertile, but grow slightly slower, produce less progeny over a prolonged period, and live longer than the wild type. These phenotypes are likely due to the moderately reduced pharyngeal pumping speed arising from the impairment of MC activity. MC neurons are still born in the ceh-19 mutants but display various morphological defects. ceh-19 expression in MC is completely lost in progeny from animals subject to RNAi for pha-4, which encodes an organ-specifying forkhead transcription factor. CEH-19 is required for the activation in MCs of the excitatory FMRFamide-like neuropeptide-encoding gene flp-2. A regulatory pathway from pha-4 through ceh-19 to flp-2 is thereby defined. The resilience of MC identity in the absence of CEH-19 may reflect the buffering qualities of transcription factor regulatory networks.
authors: School of Biology, Faculty of Biological Sciences, The University of Leeds, Leeds, LS2 9JT, United Kingdom.
authors: Huiyun
authors: H
authors: Feng
authors: Ian A
authors: IA
authors: Hope
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000235:genetics* / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005298:Fertility / Q000235:genetics; D015870:Gene Expression; D008136:Longevity / Q000235:genetics; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology; D009154:Mutation; D055495:Neurogenesis / Q000235:genetics; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D010614:Pharynx / Q000294:innervation / Q000502:physiology; D010641:Phenotype; D010802:Phylogeny; D034741:RNA, Small Interfering; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins; C583030:Flp-2 protein, C elegans; D009479:Neuropeptides; C113277:Pha-4 protein, C elegans; D034741:RNA, Small Interfering; D015534:Trans-Activators; D014157:Transcription Factors; C075433:ceh-19 protein, C elegans