Cysteine‐string proteins regulate exocytosis of insulin independent from transmembrane ion fluxes

FEBS Letters

Burgoyne, Robert D.²  Chamberlain, Luke H.²  Zhang, Hui³  Wollheim, Claes B.³  Kelley, William L.¹  Lang, Jochen³ 

[1] Département de Biochemie Médicale, Centre Médical Universitaire, CH 1211 Genève 4, Switzerland;The Physiological Laboratory, University of Liverpool, Liverpool L69 3BX, UK;Division de Biochimie Clinique, Département de Médecine Interne, Centre Médical Universitaire, CH 1211 Genève 4, Switzerland

关键词: Exocytosis;    Vesicle protein;    Calcium;    Insulin;    Cysteine string protein;    Csp;    cysteine-string protein;    HIT-T15;    hamster insulinoma cells;    INS-1E;    rat insulinoma cells;    LDCV;    large dense core vesicles;    MIN6;    mouse insulinoma cells;    RT-PCR;    reverse transcription-polymerase chain reaction;    SLMV;    synaptic-like microvesicles;    SL-O;    streptolysin-O;    SV;    synaptic vesicles;    SVP38;    synaptophysin;   

DOI  :  10.1016/S0014-5793(98)01233-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Cysteine-string proteins (Csps) are vesicle proteins involved in exocytosis of synaptic vesicles in Drosophila and modulation of presynaptic calcium influx. As both the contribution of calcium channel regulation to the role of Csp in exocytosis and a function of Csp outside the nervous system are unknown, we studied its function in endocrine exocytosis from large dense core vesicles (LDCVs) using insulin-secreting pancreatic β-cells. Csps were expressed in primary and derived β-cell lines on insulin-containing LDCVs. Suppression of Csp expression reduced not only depolarisation induced insulin release but also exocytosis in permeabilised cells directly stimulated by Ca²⁺. Thus, Csp is a secretory granule protein and is required for endocrine exocytosis independent of the modulation of transmembrane calcium fluxes.

【 授权许可】

Unknown