title: Mannosidase 2, alpha 1 deficiency is associated with ricin resistance in embryonic stem (ES) cells.
abstract: Host gene products required for mediating the action of toxins are potential targets for reversing or controlling their pathogenic impact following exposure. To identify such targets libraries of insertional gene-trap mutations generated with a PiggyBac transposon in Blm-deficient embryonic stem cells were exposed to the plant toxin, ricin. Resistant clones were isolated and genetically characterised and one was found to be a homozygous mutant of the mannosidase 2, alpha 1 (Man2α1) locus with a matching defect in the homologous allele. The causality of the molecular lesion was confirmed by removal of the transposon following expression of PB-transposase. Comparative glycomic and lectin binding analysis of the Man2α1 (-/-) ricin resistant cells revealed an increase in the levels of hybrid glycan structures and a reduction in terminal β-galactose moieties, potential target receptors for ricin. Furthermore, naïve ES cells treated with inhibitors of the N-linked glycosylation pathway at the mannosidase 2, alpha 1 step exhibited either full or partial resistance to ricin. Therefore, we conclusively identified mannosidase 2, alpha 1 deficiency to be associated with ricin resistance.
authors: The Wellcome Trust Sanger Institute, The Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, United Kingdom.
authors: Wei
authors: W
authors: Wang
authors: Christine
authors: C
authors: Hale
authors: Dave
authors: D
authors: Goulding
authors: Stuart M
authors: SM
authors: Haslam
authors: Bérangère
authors: B
authors: Tissot
authors: Christopher
authors: C
authors: Lindsay
authors: Stephen
authors: S
authors: Michell
authors: Rick
authors: R
authors: Titball
authors: Jun
authors: J
authors: Yu
authors: Ana Luisa
authors: AL
authors: Toribio
authors: Raffaella
authors: R
authors: Rossi
authors: Anne
authors: A
authors: Dell
authors: Allan
authors: A
authors: Bradley
authors: Gordon
authors: G
authors: Dougan
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D004251:DNA Transposable Elements / Q000235:genetics; D053595:Embryonic Stem Cells / Q000187:drug effects* / Q000201:enzymology* / Q000648:ultrastructure; D015723:Gene Library; D054794:Glycomics; D006031:Glycosylation / Q000187:drug effects; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional / Q000235:genetics; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism; D012276:Ricin / Q000633:toxicity*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D043323:alpha-Mannosidase / Q000172:deficiency* / Q000378:metabolism
chemical_list: D004251:DNA Transposable Elements; D011134:Polysaccharides; D012276:Ricin; D043323:alpha-Mannosidase