Neuromuscular function in plant parasitic nematodes: a target for novel control strategies?

Abstract

Over the last decade the need for new strategies and compounds to control parasitic helminths has become increasingly urgent. The neuromuscular systems of these worms have been espoused as potential sources of target molecules for new drugs which may address this need. One facet of helminth neuromuscular biology which has garnered considerable research interest is that of neuropeptidergic neurotransmission, particularly regarding parasites of humans and animals, as well as free-living nematode model species. This research interest has been piqued by the fact that neuropeptides have been demonstrated to be fundamentally important to nematode biology and thus may be of utility in this search for new drug targets. This review focuses on the neuropeptide biology of plant parasitic nematodes, a subject which has been comparatively neglected despite the fact that the search for alternative control measures also extends to these economically important parasites. We focus on the FMRFamide-like peptide (FLP) neuropeptides and the complexity and distribution of this peptide family in plant parasitic nematodes. Possible roles for FLPs in plant parasitic nematode behaviour, as elucidated by a combination of molecular imaging techniques and RNA interference (RNAi), are discussed. We propose that disruption of FLP neurosignalling in plant parasitic nematodes represents a novel form of pest control and speculate as to how this may be achieved.

Getting to the root of neuronal signalling in plant-parasitic nematodes using RNA interference

“…Beyond the interrogation of neuronal function, the potential for RNAi-based strategies of plant parasite control is well documented (see reviews by Davis et al, 2004;Bakhetia et al, 2005b;Kimber & Fleming, 2005). Indeed, the potential of using transgenic plants to generate dsRNA that would selectively disrupt target genes in infecting viral or bacterial pathogens has been reported by a number of groups (Waterhouse et al, 1998;Escobar et al, 2001;Kalantidis et al, 2002).…”

“…Despite the current (often media-led) public opposition to transgenically-based crop protection, the elegance of this technology may offer desirable and effective management of plant-parasitic nematodes through a range of GM strategies. One such approach could involve the use of nematode resistance induced by the in planta production of dsRNA molecules which trigger an RNA interference (RNAi) effect in the feeding nematodes (Davis et al, 2004;Bakhetia et al, 2005b;Kimber & Fleming, 2005). In addition to its potential in mechanisms for novel plant resistance to plant-parasitic nematodes, RNAi also provides a powerful tool with which to investigate aspects of the host-parasite interaction and deliver a greater understanding of the regulatory processes underpinning all aspects of nematode biology.…”

Novel cholinesterase paralogs ofSchistosoma mansonihave perceived roles in cholinergic signaling, glucose scavenging and drug detoxification and are essential for parasite survival

“…The nervous system of helminths has long been a potential target for therapeutic agents as it plays several crucial roles in parasite biology that are fundamental to survival, including coordinating motility within and outside of the host, feeding and reproduction [6][7][8][9][10]. The Schistosoma nervous system is particularly important in this respect as this parasite lacks a body cavity and circulating body fluid [11,12] and, as a result, its signaling functions are chiefly achieved via neurotransmission.…”

“…The primary neurotransmitter that schistosomes utilize is acetylcholine (ACh), which allows muscle contraction. The physiological concentration of ACh, however, must be maintained otherwise it triggers paralysis and this is achieved primarily through the action of AChE [6][7][8].…”

A comparison of the FMRFamide-like peptide proteolytic activities of preparations from two plant-parasitic nematodes (Heterodera glycines and Meloidogyne incognita): possible targets for novel control

“…Walker, 2011) affecting nearly all physiological events (Holden-Dye & Walker, 2011) including behaviour (Liu et al, 2007;Cohen et al, 2009), locomotion (Kimber et al, 2007), feeding (Rogers et al, 2003;Papaioannou et al, 2005), reproduction (Moffett et al, 2003) and others Kimber & Fleming, 2005).…”