Bell CA

References (2)

Title : Gastrointestinal dysfunction in patients and mice expressing the autism-associated R451C mutation in neuroligin-3 - Hosie_2019_Autism.Res_12_1043
Author(s) : Hosie S , Ellis M , Swaminathan M , Ramalhosa F , Seger GO , Balasuriya GK , Gillberg C , Rastam M , Churilov L , McKeown SJ , Yalcinkaya N , Urvil P , Savidge T , Bell CA , Bodin O , Wood J , Franks AE , Bornstein JC , Hill-Yardin EL
Ref : Autism Res , 12 :1043 , 2019
Abstract : Gastrointestinal (GI) problems constitute an important comorbidity in many patients with autism. Multiple mutations in the neuroligin family of synaptic adhesion molecules are implicated in autism, however whether they are expressed and impact GI function via changes in the enteric nervous system is unknown. We report the GI symptoms of two brothers with autism and an R451C mutation in Nlgn3 encoding the synaptic adhesion protein, neuroligin-3. We confirm the presence of an array of synaptic genes in the murine GI tract and investigate the impact of impaired synaptic protein expression in mice carrying the human neuroligin-3 R451C missense mutation (NL3(R451C) ). Assessing in vivo gut dysfunction, we report faster small intestinal transit in NL3(R451C) compared to wild-type mice. Using an ex vivo colonic motility assay, we show increased sensitivity to GABAA receptor modulation in NL3(R451C) mice, a well-established Central Nervous System (CNS) feature associated with this mutation. We further show increased numbers of small intestine myenteric neurons in NL3(R451C) mice. Although we observed altered sensitivity to GABAA receptor modulators in the colon, there was no change in colonic neuronal numbers including the number of GABA-immunoreactive myenteric neurons. We further identified altered fecal microbial communities in NL3(R451C) mice. These results suggest that the R451C mutation affects small intestinal and colonic function and alter neuronal numbers in the small intestine as well as impact fecal microbes. Our findings identify a novel GI phenotype associated with the R451C mutation and highlight NL3(R451C) mice as a useful preclinical model of GI dysfunction in autism. Autism Res 2019, 12: 1043-1056. (c) 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: People with autism commonly experience gastrointestinal problems, however the cause is unknown. We report gut symptoms in patients with the autism-associated R451C mutation encoding the neuroligin-3 protein. We show that many of the genes implicated in autism are expressed in mouse gut. The neuroligin-3 R451C mutation alters the enteric nervous system, causes gastrointestinal dysfunction, and disrupts gut microbe populations in mice. Gut dysfunction in autism could be due to mutations that affect neuronal communication.
ESTHER : Hosie_2019_Autism.Res_12_1043
PubMedSearch : Hosie_2019_Autism.Res_12_1043
PubMedID: 31119867
Gene_locus related to this paper: mouse-3neur , human-NLGN3

Title : Knockdown resistance (kdr) to DDT and pyrethroid insecticides maps to a sodium channel gene locus in the housefly (Musca domestica) - Williamson_1993_Mol.Gen.Genet_240_17
Author(s) : Williamson MS , Denholm I , Bell CA , Devonshire AL
Ref : Molecular & General Genetics , 240 :17 , 1993
Abstract : The voltage-sensitive sodium channel is generally regarded as the primary target site of dichloro-diphenyl-trichloro-ethane (DDT) and pyrethroid insecticides, and has been implicated in the widely reported mechanism of nerve insensitivity to these compounds. This phenomenon is expressed as knockdown resistance (kdr) and has been best characterised in the housefly where several putative alleles, including the more potent super-kdr factor, have been identified. We report the isolation of cDNA clones containing part of a housefly sodium channel gene, designated Msc, which show close homology to the para sodium channel of Drosophila (99% amino acid identity within the region of overlap). Using Southern blots of insect DNA, restriction fragment length polymorphisms (RFLPs) at the Msc locus were identified in susceptible, kdr and super-kdr housefly strains. These RFLPs showed tight linkage to resistance in controlled crosses involving these strains, thus providing clear genetic evidence that kdr, and hence pyrethroid mode of action, is closely associated with the voltage-sensitive sodium channel.
ESTHER : Williamson_1993_Mol.Gen.Genet_240_17
PubMedSearch : Williamson_1993_Mol.Gen.Genet_240_17
PubMedID: 8101963