title: Docking and fusion of insulin secretory granules in SUR1 knock out mouse beta-cells observed by total internal reflection fluorescence microscopy.
abstract: To explore how the sulfonylurea receptor (SUR1) is involved in docking and fusion of insulin granules, dynamic motion of single insulin secretory granules near the plasma membrane was examined in SUR1 knock-out (Sur1KO) beta-cells by total internal reflection fluorescence microscopy. Sur1KO beta-cells exhibited a marked reduction in the number of fusion events from previously docked granules. However, the number of docked granules declined during stimulation as a consequence of the release of docked granules into the cytoplasm vs. fusion with the plasma membrane. Thus, the impaired docking and fusion results in decreased insulin exocytosis from Sur1KO beta-cells.
authors.affiliation: Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611, Japan.
authors.forename: Toshiteru
authors.initials: T
authors.lastname: Kikuta
authors.forename: Mica
authors.initials: M
authors.lastname: Ohara-Imaizumi
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Nakazaki
authors.forename: Chiyono
authors.initials: C
authors.lastname: Nishiwaki
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakamichi
authors.forename: Chuwa
authors.initials: C
authors.lastname: Tei
authors.forename: Lydia
authors.initials: L
authors.lastname: Aguilar-Bryan
authors.forename: Joseph
authors.initials: J
authors.lastname: Bryan
authors.forename: Shinya
authors.initials: S
authors.lastname: Nagamatsu
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D005089:Exocytosis; D007328:Insulin / Q000032:analysis / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics*; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D022142:Secretory Vesicles / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D064233:Sulfonylurea Receptors
chemical_list: D018528:ATP-Binding Cassette Transporters; D007328:Insulin; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors; C577508:Abcc8 protein, mouse