title: Human mutation within Per-Arnt-Sim (PAS) domain-containing protein kinase (PASK) causes basal insulin hypersecretion.
abstract: PAS kinase (PASK) is a glucose-regulated protein kinase involved in the control of pancreatic islet hormone release and insulin sensitivity. We aimed here to identify mutations in the PASK gene that may be associated with young-onset diabetes in humans. We screened 18 diabetic probands with unelucidated maturity-onset diabetes of the young (MODY). We identified two rare nonsynonymous mutations in the PASK gene (p.L1051V and p.G1117E), each of which was found in a single MODY family. Wild type or mutant PASKs were expressed in HEK 293 cells. Kinase activity of the affinity-purified proteins was assayed as autophosphorylation at amino acid Thr307 or against an Ugp1p-derived peptide. Whereas the PASK p.G1117E mutant displayed a ∼25% increase with respect to wild type PASK in the extent of autophosphorylation, and a ∼2-fold increase in kinase activity toward exogenous substrates, the activity of the p.L1051V mutant was unchanged. Amino acid Gly1117 is located in an α helical region opposing the active site of PASK and may elicit either: (a) a conformational change that increases catalytic efficiency or (b) a diminished inhibitory interaction with the PAS domain. Mouse islets were therefore infected with adenoviruses expressing wild type or mutant PASK and the regulation of insulin secretion was examined. PASK p.G1117E-infected islets displayed a 4-fold decrease in glucose-stimulated (16.7 versus 3 mM) insulin secretion, chiefly reflecting a 4.5-fold increase in insulin release at low glucose. In summary, we have characterized a rare mutation (p.G1117E) in the PASK gene from a young-onset diabetes family, which modulates glucose-stimulated insulin secretion.
authors: Department of Medicine, Section of Cell Biology, Division of Diabetes Endocrinology and Metabolism, Imperial College London, London SW7 2AZ, United Kingdom.
authors: Francesca
authors: F
authors: Semplici
authors: CNRS-UMR-8199, Pasteur Institute of Lille, BP245 59019 Lille Cedex, France; Lille Nord de France University, BP245 59019 Lille Cedex, France.
authors: Martine
authors: M
authors: Vaxillaire
authors: University of Utah School of Medicine, Salt Lake City, Utah 84132-3201.
authors: Sarah
authors: S
authors: Fogarty
authors: Montreal Diabetes Research Center, CRCHUM, University of Montréal, Québec, Canada.
authors: Meriem
authors: M
authors: Semache
authors: CNRS-UMR-8199, Pasteur Institute of Lille, BP245 59019 Lille Cedex, France; Lille Nord de France University, BP245 59019 Lille Cedex, France.
authors: Amélie
authors: A
authors: Bonnefond
authors: Montreal Diabetes Research Center, CRCHUM, University of Montréal, Québec, Canada.
authors: Ghislaine
authors: G
authors: Fontés
authors: CNRS-UMR-8199, Pasteur Institute of Lille, BP245 59019 Lille Cedex, France; Lille Nord de France University, BP245 59019 Lille Cedex, France.
authors: Julien
authors: J
authors: Philippe
authors: Department of Medicine, Section of Cell Biology, Division of Diabetes Endocrinology and Metabolism, Imperial College London, London SW7 2AZ, United Kingdom.
authors: Gargi
authors: G
authors: Meur
authors: Centre for Research in Biomedicine, Faculty of Health and Life Sciences, University of the West of England, Bristol BS16 1QY, United Kingdom.
authors: Frederique
authors: F
authors: Diraison
authors: Department of Biochemistry, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom.
authors: Richard B
authors: RB
authors: Sessions
authors: University of Utah School of Medicine, Salt Lake City, Utah 84132-3201.
authors: Jared
authors: J
authors: Rutter
authors: Montreal Diabetes Research Center, CRCHUM, University of Montréal, Québec, Canada; Department of Medicine, University of Montréal, Montréal QC H1W 4A4 Québec, Canada.
authors: Vincent
authors: V
authors: Poitout
authors: CNRS-UMR-8199, Pasteur Institute of Lille, BP245 59019 Lille Cedex, France; Lille Nord de France University, BP245 59019 Lille Cedex, France; Department of Genomics of Common Disease, School of Public Health, Imperial College London, London SW7 2AZ, United Kingdom.
authors: Philippe
authors: P
authors: Froguel
authors: Department of Medicine, Section of Cell Biology, Division of Diabetes Endocrinology and Metabolism, Imperial College London, London SW7 2AZ, United Kingdom. Electronic address: g.rutter@imperial.ac.uk.
authors: Guy A
authors: GA
authors: Rutter
mesh_terms: D000328:Adult; D000818:Animals; D002460:Cell Line; D003920:Diabetes Mellitus / Q000378:metabolism; D023281:Genomics; D005934:Glucagon / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D057809:HEK293 Cells; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008957:Models, Genetic; D016296:Mutagenesis; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D018840:HSP70 Heat-Shock Proteins; D007328:Insulin; D008565:Membrane Proteins; D011994:Recombinant Proteins; C018551:glucose-regulated proteins; D005934:Glucagon; C116037:PAS domain kinases; D017346:Protein Serine-Threonine Kinases; D005947:Glucose