Docking and fusion of insulin secretory granules in SUR1 knock out mouse beta-cells observed by total internal reflection fluorescence microscopy.
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.
Kikuta
Toshiteru
T
Department of Biochemistry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611, Japan.
Ohara-Imaizumi
Mica
M
Nakazaki
Mitsuhiro
M
Nishiwaki
Chiyono
C
Nakamichi
Yoko
Y
Tei
Chuwa
C
Aguilar-Bryan
Lydia
L
Bryan
Joseph
J
Nagamatsu
Shinya
S
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
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