Stimulation of insulin release from permeabilized HIT‐T15 cells by a synthetic peptide corresponding to the effector domain of the small GTP‐binding protein rab3

FEBS Letters

Balch, William E.¹  Regazzi, Romano²  Wollheim, Claes B.²  Li, Guodong² 

[1] Department of Molecular Biology, Research Institute of Scripps Clinic, La Jolla, CA 92037, USA;Division de Biochimie Clinique, Département de Médecine, Centre Médical Universitaire, CH-1211 Geneva 4, Switzerland (member of the Geneva Diabetes Group)

关键词: GTP-binding protein;    Insulin secretion;    Calcium;    Rab protein;    Exocytosis;    G-protein;    GTP-binding protein;    SMGs;    small molecular weight GTP-binding proteins;    GAP;    GTPase-activating protein;    GDI;    GDP-dissociation inhibitor;    GDS;    GDP-dissociation stimulator;    GDPβS;    guanosine 5'-O-(2-thiodiphosphate);    GTPγS;    guanosine-5'-O-(3-thiotrisphosphate);    SL-O;    streptolysin-O;   

DOI  :  10.1016/0014-5793(93)80159-R

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A synthetic peptide (rab3AL) corresponding to the effector domain of rab3, a small GTP-binding protein, stimulated basal and potentiated Ca²⁺-as well as GTPγS-evoked insulin secretion about 2-fold from streptolysin-O permeabilized HIT cells. This effect was specific, since the analogous peptides of ras or rab1 did not affect the exocytotic event. The more than additive effect of rab3AL on Ca²⁺ or GTPγS stimulation indicates a distinct mode of action of the peptide. The partial loss of cytosolic proteins from permeabilized cells was accompanied by a faster run-down of the secretory response to Ca²⁺ than the one to GTPγS. The persistent effect of rab3AL under these conditions points to a membrane localization of its target. These results suggest that rab3 and its effector are involved in the regulation of insulin secretion.

【 授权许可】

Unknown