David B Sattelle

University of Bath, Bath, ENG, United Kingdom

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Publications (88)474.17 Total impact

  • Source
    Dataset: Tribolium-suppl-nature06784-s1[1]
  • Source
    Dataset: 099.nature.2006.443.0931.gutell.suppl
  • Article: Xenopus laevis RIC-3 enhances the functional expression of the C. elegans homomeric nicotinic receptor, ACR-16, in Xenopus oocytes.
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    ABSTRACT: RIC-3 enhances the functional expression of certain nicotinic acetylcholine receptors (nAChRs) in vertebrates and invertebrates and increases the availability of functional receptors in cultured cells and Xenopus laevis oocytes. Maximal activity of RIC-3 may be cell-type dependent, so neither mammalian nor invertebrate proteins is optimal in amphibian oocytes. We cloned the X. laevis ric-3 cDNA and tested the frog protein in oocyte expression studies. X. laevis RIC-3 shares 52% amino acid identity with human RIC-3 and only 17% with that of Caenorhabditis elegans. We used the C. elegans nicotinic receptor, ACR-16, to compare the ability of RIC-3 from three species to enhance receptor expression. In the absence of RIC-3, the proportion of oocytes expressing detectable nAChRs was greatly reduced. Varying the ratio of acr-16 to X. laevis ric-3 cRNAs injected into oocytes had little impact on the total cell current. When X. laevis, human or C. elegans ric-3 cRNAs were co-injected with acr-16 cRNA (1 : 1 ratio), 100 μM acetylcholine induced larger currents in oocytes expressing X. laevis RIC-3 compared with its orthologues. This provides further evidence for a species-specific component of RIC-3 activity, and suggests that X. laevis RIC-3 is useful for enhancing the expression of invertebrate nAChRs in X. laevis oocytes.
    Journal of Neurochemistry 09/2012; · 4.06 Impact Factor
  • Article: Invertebrate models of spinal muscular atrophy: insights into mechanisms and potential therapeutics.
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    ABSTRACT: Invertebrate genetic models with their tractable neuromuscular systems are effective vehicles for the study of human nerve and muscle disorders. This is exemplified by insights made into spinal muscular atrophy (SMA) using the fruit fly Drosophila melanogaster and the nematode worm Caenorhabditis elegans. For speed and economy, these invertebrates offer convenient, whole-organism platforms for genetic screening as well as RNA interference (RNAi) and chemical library screens, permitting the rapid testing of hypotheses related to disease mechanisms and the exploration of new therapeutic routes and drug candidates. Here, we discuss recent developments encompassing synaptic physiology, RNA processing, and screening of compound and genome-scale RNAi libraries, showcasing the importance of invertebrate SMA models.
    BioEssays 12/2011; 33(12):956-65. · 4.95 Impact Factor
  • Article: Glutamate-gated chloride channels of Haemonchus contortus restore drug sensitivity to ivermectin resistant Caenorhabditis elegans.
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    ABSTRACT: Anthelmintic resistance is a major problem in livestock farming, especially of small ruminants, but our understanding of it has been limited by the difficulty in carrying out functional genetic studies on parasitic nematodes. An important nematode infecting sheep and goats is Haemonchus contortus; in many parts of the world this species is resistant to almost all the currently available drugs, including ivermectin. It is extremely polymorphic and to date it has proved impossible to relate any sequence polymorphisms to its ivermectin resistance status. Expression of candidate drug-resistance genes in Caenorhabditis elegans could provide a convenient means to study the effects of polymorphisms found in resistant parasites, but may be complicated by differences between the gene families of target and model organisms. We tested this using the glutamate-gated chloride channel (GluCl) gene family, which forms the ivermectin drug target and are candidate resistance genes. We expressed GluCl subunits from C. elegans and H. contortus in a highly resistant triple mutant C. elegans strain (DA1316) under the control of the avr-14 promoter; expression of GFP behind this promoter recapitulated the pattern previously reported for avr-14. Expression of ivermectin-sensitive subunits from both species restored drug sensitivity to transgenic worms, though some quantitative differences were noted between lines. Expression of an ivermectin-insensitive subunit, Hco-GLC-2, had no effect on drug sensitivity. Expression of a previously uncharacterised parasite-specific subunit, Hco-GLC-6, caused the transgenic worms to become ivermectin sensitive, suggesting that this subunit also encodes a GluCl that responds to the drug. These results demonstrate that both orthologous and paralogous subunits from C. elegans and H. contortus are able to rescue the ivermectin sensitivity of mutant C. elegans, though some quantitative differences were observed between transgenic lines in some assays. C. elegans is a suitable system for studying parasitic nematode genes that may be involved in drug resistance.
    PLoS ONE 01/2011; 6(7):e22390. · 4.09 Impact Factor
  • Article: Proteins interacting with nicotinic acetylcholine receptors: expanding functional and therapeutic horizons.
    Andrew K Jones, Steven D Buckingham, David B Sattelle
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    ABSTRACT: Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that carry out the fast actions of the neurotransmitter acetylcholine (ACh). Over the past 30 years, it has become clear that the activity of nAChRs is dependent on their interaction with a host of proteins, and the number of these that have been identified has increased considerably with recent large-scale proteomic analyses. This review focuses on these interacting proteins, discussing how they regulate a wide range of functions including receptor assembly, and trafficking to and from the cell surface, as well as how they directly modulate functional characteristics such as sensitivity and the degree of response to ACh. Mutations giving rise to disease states highlight the importance of these interacting proteins. Here, we consider their potential as future therapeutic targets for treating diseases associated with altered nAChR function.
    Trends in Pharmacological Sciences 10/2010; 31(10):455-62. · 10.93 Impact Factor
  • Article: A novel Caenorhabditis elegans allele, smn-1(cb131), mimicking a mild form of spinal muscular atrophy, provides a convenient drug screening platform highlighting new and pre-approved compounds.
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    ABSTRACT: Spinal muscular atrophy (SMA), an autosomal recessive genetic disorder, is characterized by the selective degeneration of lower motor neurons, leading to muscle atrophy and, in the most severe cases, paralysis and death. Deletions and point mutations cause reduced levels of the widely expressed survival motor neuron (SMN) protein, which has been implicated in a range of cellular processes. The mechanisms underlying disease pathogenesis are unclear, and there is no effective treatment. Several animal models have been developed to study SMN function including the nematode, Caenorhabditis elegans, in which a large deletion in the gene homologous to SMN, smn-1, results in neuromuscular dysfunction and larval lethality. Although useful, this null mutant, smn-1(ok355), is not well suited to drug screening. We report the isolation and characterization of smn-1(cb131), a novel allele encoding a substitution in a highly conserved residue of exon 2, resembling a point mutation found in a patient with type IIIb SMA. The smn-1(cb131) animals display milder yet similar defects when compared with the smn-1 null mutant. Using an automated phenotyping system, mutants were shown to swim slower than wild-type animals. This phenotype was used to screen a library of 1040 chemical compounds for drugs that ameliorate the defect, highlighting six for subsequent testing. 4-aminopyridine, gaboxadol hydrochloride and N-acetylneuraminic acid all rescued at least one aspect of smn-1 phenotypic dysfunction. These findings may assist in accelerating the development of drugs for the treatment of SMA.
    Human Molecular Genetics 10/2010; 20(2):245-60. · 7.64 Impact Factor
  • Article: A Cys-loop mutation in the Caenorhabditis elegans nicotinic receptor subunit UNC-63 impairs but does not abolish channel function.
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    ABSTRACT: The nematode Caenorhabditis elegans is an established model organism for studying neurobiology. UNC-63 is a C. elegans nicotinic acetylcholine receptor (nAChR) α-subunit. It is an essential component of the levamisole-sensitive muscle nAChR (L-nAChR) and therefore plays an important role in cholinergic transmission at the nematode neuromuscular junction. Here, we show that worms with the unc-63(x26) allele, with its αC151Y mutation disrupting the Cys-loop, have deficient muscle function reflected by impaired swimming (thrashing). Single-channel recordings from cultured muscle cells from the mutant strain showed a 100-fold reduced frequency of opening events and shorter channel openings of L-nAChRs compared with those of wild-type worms. Anti-UNC-63 antibody staining in both cultured adult muscle and embryonic cells showed that L-nAChRs were expressed at similar levels in the mutant and wild-type cells, suggesting that the functional changes in the receptor, rather than changes in expression, are the predominant effect of the mutation. The kinetic changes mimic those reported in patients with fast-channel congenital myasthenic syndromes. We show that pyridostigmine bromide and 3,4-diaminopyridine, which are drugs used to treat fast-channel congenital myasthenic syndromes, partially rescued the motility defect seen in unc-63(x26). The C. elegans unc-63(x26) mutant may therefore offer a useful model to assist in the development of therapies for syndromes produced by altered function of human nAChRs.
    Journal of Biological Chemistry 10/2010; 286(4):2550-8. · 4.77 Impact Factor
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    Article: Functional and evolutionary insights from the genomes of three parasitoid Nasonia species.
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    ABSTRACT: We report here genome sequences and comparative analyses of three closely related parasitoid wasps: Nasonia vitripennis, N. giraulti, and N. longicornis. Parasitoids are important regulators of arthropod populations, including major agricultural pests and disease vectors, and Nasonia is an emerging genetic model, particularly for evolutionary and developmental genetics. Key findings include the identification of a functional DNA methylation tool kit; hymenopteran-specific genes including diverse venoms; lateral gene transfers among Pox viruses, Wolbachia, and Nasonia; and the rapid evolution of genes involved in nuclear-mitochondrial interactions that are implicated in speciation. Newly developed genome resources advance Nasonia for genetic research, accelerate mapping and cloning of quantitative trait loci, and will ultimately provide tools and knowledge for further increasing the utility of parasitoids as pest insect-control agents.
    Science 01/2010; 327(5963):343-8. · 31.20 Impact Factor
  • Article: Diversity of insect nicotinic acetylcholine receptor subunits.
    Andrew K Jones, David B Sattelle
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    ABSTRACT: Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that mediate fast synaptic transmission in the insect nervous system and are targets of a major group of insecticides, the neonicotinoids. They consist of five subunits arranged around a central ion channeL Since the subunit composition determines the functional and pharmacological properties of the receptor the presence of nAChR families comprising several subunit-encodinggenes provides a molecular basis for broad functional diversity. Analyses of genome sequences have shown that nAChR gene families remain compact in diverse insect species, when compared to their nematode andvertebrate counterparts. Thus, the fruit fly (Drosophila melanogaster), malaria mosquito (Anopheles gambiae), honey bee (Apis mellifera), silk worm (Bombyx mon) and the red flour beetle (Tribolium castaneum) possess 10-12 nAChR genes while human and the nematode Caenorhabditis elegans have 16 and 29 respectively. Although insect nAChRgene families are amongst the smallest known, receptor diversity can be considerably increased by the posttranscriptional processes alternative splicing and mRNA A-to-I editingwhich can potentially generate protein products which far outnumber the nAChR genes. These two processes can also generate species-specific subunit isoforms. In addition, each insect possesses at least one highly divergent nAChR subunit which may perform species-specific functions. Species-specific subunit diversification may offer promising targets for future rational design of insecticides that target specific pest insects while sparing beneficial species.
    Advances in experimental medicine and biology 01/2010; 683:25-43. · 1.09 Impact Factor
  • Article: The nicotinic acetylcholine receptors of the parasitic nematode Ascaris suum: formation of two distinct drug targets by varying the relative expression levels of two subunits.
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    ABSTRACT: Parasitic nematodes are of medical and veterinary importance, adversely affecting human health and animal welfare. Ascaris suum is a gastrointestinal parasite of pigs; in addition to its veterinary significance it is a good model of the human parasite Ascaris lumbricoides, estimated to infect approximately 1.4 billion people globally. Anthelmintic drugs are essential to control nematode parasites, and nicotinic acetylcholine receptors (nAChRs) on nerve and muscle are the targets of cholinergic anthelmintics such as levamisole and pyrantel. Previous genetic analyses of nematode nAChRs have been confined to Caenorhabditis elegans, which is phylogenetically distinct from Ascaris spp. and many other important parasites. Here we report the cloning and expression of two nAChR subunit cDNAs from A. suum. The subunits are very similar in sequence to C. elegans UNC-29 and UNC-38, are expressed on muscle cells and can be expressed robustly in Xenopus oocytes to form acetylcholine-, nicotine-, levamisole- and pyrantel-sensitive channels. We also demonstrate that changing the stoichiometry of the receptor by injecting different ratios of the subunit cRNAs can reproduce two of the three pharmacological subtypes of nAChR present in A. suum muscle cells. When the ratio was 5:1 (Asu-unc-38ratioAsu-unc-29), nicotine was a full agonist and levamisole was a partial agonist, and oocytes responded to oxantel, but not pyrantel. At the reverse ratio (1:5 Asu-unc-38ratioAsu-unc-29), levamisole was a full agonist and nicotine was a partial agonist, and the oocytes responded to pyrantel, but not oxantel. These results represent the first in vitro expression of any parasitic nicotinic receptor and show that their properties are substantially different from those of C. elegans. The results also show that changing the expression level of a single receptor subunit dramatically altered the efficacy of some anthelmintic drugs. In vitro expression of these subunits may permit the development of parasite-specific screens for future anthelmintics.
    PLoS Pathogens 08/2009; 5(7):e1000517. · 9.13 Impact Factor
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    Article: Comparative pharmacology and computational modelling yield insights into allosteric modulation of human alpha7 nicotinic acetylcholine receptors.
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    ABSTRACT: The human alpha7 nicotinic acetylcholine receptor (nAChR) subunit and its Caenorhabditis elegans homolog, ACR-16, can generate functional recombinant homomeric receptors when expressed in Xenopus laevis oocytes. Both nAChRs express robustly in the presence of the co-injected chaperone, RIC-3, and show striking differences in the actions of a type I positive allosteric modulator (PAM), ivermectin (IVM). Type I PAMs are characterised by an increase in amplitude only of the response to acetylcholine (ACh), whereas type II PAMs exhibit, in addition, changes in time-course/desensitization of the ACh response. The type I PAMs, ivermectin, 5-hydroxyindole (5-HI), NS-1738 and genistein and the type II PAM, PNU-120596, are all active on human alpha7 but are without PAM activity on ACR-16, where they attenuate the amplitude of the ACh response. We used the published structure of avermectin B1a to generate a model of IVM, which was then docked into the candidate transmembrane allosteric binding site on alpha7 and ACR-16 in an attempt to gain insights into the observed differences in IVM actions. The new pharmacological findings and computational approaches being developed may inform the design of novel PAM drugs targeting major neurological disorders.
    Biochemical pharmacology 07/2009; 78(7):836-43. · 4.25 Impact Factor
  • Article: Splice-variant- and stage-specific RNA editing of the Drosophila GABA receptor modulates agonist potency.
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    ABSTRACT: The molecular diversity of many gene products functioning in the nervous system is enhanced by alternative splicing and adenosine-to-inosine editing of pre-mRNA. Using RDL, a Drosophila melanogaster GABA-gated ion channel, we examined the functional impact of RNA editing at several sites along with alternative splicing of more than one exon. We show that alternative splicing and RNA editing have a combined influence on the potency of the neurotransmitter GABA, and the editing isoforms detected in vivo span the entire functional range of potencies seen for all possible edit variants expressed in Xenopus laevis oocytes. The extent of RNA editing is developmentally regulated and can also be linked to the choice of alternative exons. These results provide insights into how the rich diversity of signaling necessary for complex brain function can be achieved by relatively few genes.
    Journal of Neuroscience 05/2009; 29(13):4287-92. · 7.11 Impact Factor
  • Article: Diverse actions and target-site selectivity of neonicotinoids: structural insights.
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    ABSTRACT: The nicotinic acetylcholine receptors (nAChRs) are targets for human and veterinary medicines as well as insecticides. Subtype-selectivity among the diverse nAChR family members is important for medicines targeting particular disorders, and pest-insect selectivity is essential for the development of safer, environmentally acceptable insecticides. Neonicotinoid insecticides selectively targeting insect nAChRs have important applications in crop protection and animal health. Members of this class exhibit strikingly diverse actions on their nAChR targets. Here we review the chemistry and diverse actions of neonicotinoids on insect and mammalian nAChRs. Electrophysiological studies on native nAChRs and on wild-type and mutagenized recombinant nAChRs have shown that basic residues particular to loop D of insect nAChRs are likely to interact electrostatically with the nitro group of neonicotinoids. In 2008, the crystal structures were published showing neonicotinoids docking into the acetylcholine binding site of molluscan acetylcholine binding proteins with homology to the ligand binding domain (LBD) of nAChRs. The crystal structures showed that 1) glutamine in loop D, corresponding to the basic residues of insect nAChRs, hydrogen bonds with the NO(2) group of imidacloprid and 2) neonicotinoid-unique stacking and CH-pi bonds at the LBD. A neonicotinoid-resistant strain obtained by laboratory-screening has been found to result from target site mutations, and possible reasons for this are also suggested by the crystal structures. The prospects of designing neonicotinoids that are safe not only for mammals but also for beneficial insects such as honey bees (Apis mellifera) are discussed in terms of interactions with non-alpha nAChR subunits.
    Molecular pharmacology 04/2009; 76(1):1-10. · 4.53 Impact Factor
  • Article: Nicotinic acetylcholine receptor signalling: roles in Alzheimer's disease and amyloid neuroprotection.
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    ABSTRACT: Alzheimer's disease (AD), the major contributor to dementia in the elderly, involves accumulation in the brain of extracellular plaques containing the beta-amyloid protein (Abeta) and intracellular neurofibrillary tangles of hyperphosphorylated tau protein. AD is also characterized by a loss of neurons, particularly those expressing nicotinic acetylcholine receptors (nAChRs), thereby leading to a reduction in nAChR numbers. The Abeta(1-42) protein, which is toxic to neurons, is critical to the onset and progression of AD. The discovery of new drug therapies for AD is likely to be accelerated by an improved understanding of the mechanisms whereby Abeta causes neuronal death. We examine the evidence for a role in Abeta(1-42) toxicity of nAChRs; paradoxically, nAChRs can also protect neurons when activated by nicotinic ligands. Abeta peptides and nicotine differentially activate several intracellular signaling pathways, including the phosphatidylinositol 3-kinase/v-akt murine thymoma viral oncogene homolog pathway, the extracellular signal-regulated kinase/mitogen-activated protein kinase, and JAK-2/STAT-3 pathways. These pathways control cell death or survival and the secretion of Abeta peptides. We propose that understanding the differential activation of these pathways by nicotine and/or Abeta(1-42) may offer the prospect of new routes to therapy for AD.
    Pharmacological reviews 04/2009; 61(1):39-61. · 17.00 Impact Factor
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    Article: Deletion of smn-1, the Caenorhabditis elegans ortholog of the spinal muscular atrophy gene, results in locomotor dysfunction and reduced lifespan.
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    ABSTRACT: Spinal muscular atrophy is the most common genetic cause of infant mortality and is characterized by degeneration of lower motor neurons leading to muscle wasting. The causative gene has been identified as survival motor neuron (SMN). The invertebrate model organism Caenorhabditis elegans contains smn-1, the ortholog of human SMN. Caenorhabditis elegans smn-1 is expressed in various tissues including the nervous system and body wall muscle, and knockdown of smn-1 by RNA interference is embryonic lethal. Here we show that the smn-1(ok355) deletion, which removes most of smn-1 including the translation start site, produces a pleiotropic phenotype including late larval arrest, reduced lifespan, sterility as well as impaired locomotion and pharyngeal activity. Mutant nematodes develop to late larval stages due to maternal contribution of the smn-1 gene product that allows to study SMN-1 functions beyond embryogenesis. Neuronal, but not muscle-directed, expression of smn-1 partially rescues the smn-1(ok355) phenotype. Thus, the deletion mutant smn-1(ok355) provides a useful platform for functional analysis of an invertebrate ortholog of the human SMN protein.
    Human Molecular Genetics 11/2008; 18(1):97-104. · 7.64 Impact Factor
  • Article: Strategies for automated analysis of C. elegans locomotion.
    Steven D Buckingham, David B Sattelle
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    ABSTRACT: Automated analysis of C. elegans behaviour is a rapidly developing field, offering the possibility of behaviour-based, high-throughput drug screens and systematic phenotyping. Standard methods for parameterizing worm shapes and movements are emerging, and progress has been made towards overcoming the difficulties introduced by interactions between worms, as well as worm coiling and omega turning. Current methods have facilitated the identification of subtle phenotypes and the characterisation of roles of neurones in forward locomotion and chemotaxis, as well as the quantitative characterisation of behaviour choice and circadian patterns of activity. Given the speed with which C. elegans has been deployed in genetic screens and chemical screens, it is to be hoped that wormtrackers may eventually provide similar rapidity in assaying behavioural phenotypes. However, considerable progress must be made before this can be accomplished. In the case of genome-wide RNAi screens, for example, the presence in the worm genome of some 19,000 genes means that even the minimal user intervention in an automatic phenotyping system will be very costly. Nonetheless, recent advances have shown that drug actions on large numbers of worms can be tracked, raising hopes that high-throughput behavioural screens may soon be available.
    Invertebrate Neuroscience 10/2008; 8(3):121-31. · 1.32 Impact Factor
  • Article: Insect ryanodine receptors: molecular targets for novel pest control chemicals.
    David B Sattelle, Daniel Cordova, Timothy R Cheek
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    ABSTRACT: Ryanodine receptors (RyRs) are a distinct class of ligand-gated calcium channels controlling the release of calcium from intracellular stores. They are located on the sarcoplasmic reticulum of muscle and the endoplasmic reticulum of neurons and many other cell types. Ryanodine, a plant alkaloid and an important ligand used to characterize and purify the receptor, has served as a natural botanical insecticide, but attempts to generate synthetic commercial analogues of ryanodine have proved unsuccessful. Recently two classes of synthetic chemicals have emerged resulting in commercial insecticides that target insect RyRs. The phthalic acid diamide class has yielded flubendiamide, the first synthetic ryanodine receptor insecticide to be commercialized. Shortly after the discovery of the phthalic diamides, the anthranilic diamides were discovered. This class has produced the insecticides Rynaxypyr and Cyazypyr. Here we review the structure and functions of insect RyRs and address the modes of action of phthalic acid diamides and anthranilic diamides on insect ryanodine receptors. Particularly intersting is the inherent selectivity both chemical classes exhibit for insect RyRs over their mammalian counterparts. The future prospects for RyRs as a commercially-validated target site for insect control chemicals are also considered.
    Invertebrate Neuroscience 10/2008; 8(3):107-19. · 1.32 Impact Factor
  • Article: Combined roles of loops C and D in the interactions of a neonicotinoid insecticide imidacloprid with the alpha4beta2 nicotinic acetylcholine receptor.
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    ABSTRACT: Neonicotinoid insecticides are widely used for crop protection based on their selective actions on insect nicotinic acetylcholine receptors (insect nAChRs). Loops C and D in insect nAChRs have been shown to possess structural features favorable for neonicotinoid-nAChR interactions. However, it remains to be resolved whether such features serve either co-operatively, or independently, to enhance neonicotinoid sensitivity of nAChRs. We therefore examined using voltage-clamp electrophysiology the effects on the response to imidacloprid of combinatorial substitutions of residues in loops C and D of the chicken alpha4beta2 nAChR by those present in insect nAChRs. The E219P mutation in loop C of the alpha4 subunit resulted in enhanced responses to imidacloprid of alpha4beta2, whereas E219S and E219T mutations barely influenced its actions. On the other hand, mutations in loop D (T77R; E79V and T77N; E79R) alone shifted the imidacloprid concentration-response curve to the left (lower concentrations). Interestingly, all three mutations did, however, further enhance the agonist efficacy of imidacloprid when combined with the mutations in loop D. Such synergistic effects of the two loops on the interactions with imidaclprid were observed irrespective of subunit stoichiometry. Computational modeling of the ligand binding domain of the wild-type and mutant alpha4beta2 nAChRs using the crystal structure of the acetylcholine binding protein from Lymnaea stagnalis also indicated that interactions with loop F of loops C and D may contribute to determining the response to imidacloprid.
    Neuropharmacology 09/2008; 56(1):264-72. · 4.81 Impact Factor
  • Article: A role for Leu118 of loop E in agonist binding to the alpha 7 nicotinic acetylcholine receptor.
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    ABSTRACT: Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels mediating fast cholinergic synaptic transmission in the brain and at neuromuscular junctions. We used the structure of the acetylcholine binding protein from Lymnaea stagnalis to model the chicken alpha7 agonist-binding domain. The initial models and a preliminary docking study suggested that position Leu118 may play an important role in determining agonist actions on alpha7. A prediction from these in silico studies, that L118E and L118D would retain binding to acetylcholine but L118K and L118R would not, was confirmed in electrophysiological studies on functional recombinant mutant receptors expressed in Xenopus laevis oocytes. The functional studies also demonstrated that residues at position 118 have a dramatic effect on the actions of imidacloprid (a partial agonist of wild-type alpha7 receptors) and its des-nitro derivative. Molecular dynamics simulations confirmed that Leu118 can strongly influence agonist binding and that the model was robust in terms of its prediction for acetylcholine binding. Together, the results indicate a role for Leu118 in influencing agonist actions on alpha7 nAChRs.
    Molecular pharmacology 07/2008; 73(6):1659-67. · 4.53 Impact Factor

Institutions

  • 2009–2012
    • University of Bath
      • Department of Biology and Biochemistry
      Bath, ENG, United Kingdom
  • 2002–2011
    • University of Oxford
      • • Department of Physiology, Anatomy and Genetics
      • • MRC Functional Genomics Unit
      Oxford, ENG, United Kingdom
  • 2002–2009
    • Kinki University
      • Faculty of Agriculture
      Ōsaka-shi, Osaka-fu, Japan
  • 1991–2008
    • University of Cambridge
      • Department of Zoology
      Cambridge, ENG, United Kingdom
  • 2007
    • Université d'Angers
      • Faculté de médecine
      Angers, Pays de la Loire, France
  • 2006
    • University College London
      • Department of Pharmacology
      London, ENG, United Kingdom