Timothy G. Geary

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INTRODUCTION While we lack a complete understanding of the molecular mechanisms by which parasites establish and achieve protection from host immune responses, it is accepted that many of these processes are mediated by products, primarily proteins, released from the parasite. Parasitic nematodes occur in different life stages and anatomical compartments(More)
Nervous systems of helminths are highly peptidergic. Species in the phylum Nematoda (roundworms) possess at least 50 FMRFamide-related peptides (FaRPs), with more yet to be identified. To date, few non-FaRP neuropeptides have been identified in these organisms, though evidence suggests that other families are present. FaRPergic systems have important(More)
A large number of FMRFamide-related peptides (FaRPs) are found in nematodes, and some of these are known to influence tension and contractility of neuromuscular strips isolated from Ascaris suum body wall. Relaxation of these strips has been noted with five nematode FaRPs. The inhibitory actions of SDPNFLRFamide (PF1) and SADPNFLRFamide (PF2) appear to be(More)
The central role of FMRFamide-like peptides (FLPs) in nematode motor and sensory capabilities makes FLP signalling an appealing target for new parasiticides. Accumulating evidence has revealed an astounding level of FLP sequence conservation and diversity in the phylum Nematoda, and preliminary work has begun to identify the nematode FLP receptor complement(More)
Caenorhabditis elegans possesses 22 FMRFamide-like peptide (flp) genes predicted to encode 60 different FMRFamide-related peptides with a range of C-terminal signatures. Peptides from five flp genes (1, 6, 8, 9 and 14) are known to modulate the ovijector of Ascaris suum in vitro. This study examines the physiological effects of peptides from the remaining(More)
  • T G Geary, D A Price, J W Bowman, C A Winterrowd, C D Mackenzie, R D Garrison +2 others
  • 1992
Peptides of the FXRFamide family, where X = M, I or L, are broadly distributed among invertebrates. Two such peptides were purified and sequenced from the free-living nematode, Panagrellus redivivus. Immunohistochemical techniques localized FMRFamide-like material in several regions of these organisms, including the nerve cords and, most prominently, in(More)
1. The physiological effects of two Phe-Met-Arg-Phe-NH2 (FMRFamide)-related neuropeptides isolated from the free-living nematode Panagrellus redivivus, SDPNFLRFamide (PF1) and SADPNFLRFamide (PF2), were examined using neuromuscular preparations from the parasitic nematode Ascaris suum. 2. PF1 and PF2 hyperpolarized muscle membrane and induced sustained(More)
The occurrence of classical neurotransmitter molecules and numerous peptidic messenger molecules in nematode nervous systems indicate that although structurally simple, nematode nervous systems are chemically complex. Thus far, studies on one nematode neuropeptide family, namely the FMRFamide-related peptides (FaRPs), have revealed an unexpected variety of(More)
Despite a simple nervous system, the free-living nematode Caenorhabditis elegans exhibits complex behaviors. The identification of peptide ligands for a G-protein-coupled receptor (GPCR) has provided insight into the neuronal circuitry involved in the regulation of feeding behavior in this worm. Progress in this regard has been accelerated by the discovery(More)
This study reports a series of systematic BLAST searches of nematode ESTs on the Genbank database, using search strings derived from known nematode FLPs (those encoded by Caenorhabditis elegans flp genes as well as those isolated from other nematodes including Ascaris suum), as well as query sequences representative of theoretical FLPs. Over 1000 putative(More)