Povzetek
SNAP-25 is a protein of the core SNARE complex mediating stimulus-dependent release of insulin from pancreatic [beta] cells. The protein exists as two alternatively spliced isoforms, SNAP-25a and SNAP-25b, differing in 9 out of 206 amino acids, yet their specific roles in pancreatic [beta] cells remain unclear. We explored the effect of SNAP-25b-deficiency on glucose-stimulated insulin release in islets and found increased secretion both in vivo and in vitro. However, slow photo-release of caged Ca2+ in [beta] cells within pancreatic slices showed no significant differences in Ca2+-sensitivity, amplitude or rate of exocytosis between SNAP-25b-deficient and wild-type littermates. Therefore, we next investigated if Ca2+ handling was affected in glucose-stimulated [beta] cells using intracellular Ca2+-imaging and found premature activation and delayed termination of [Ca2+] i elevations. These findings were accompanied by less synchronized Ca2+-oscillations and hence more segregated functional [beta] cell networks in SNAP-25b-deficient mice. Islet gross morphology and architecture were maintained in mutant mice, although sex specific compensatory changes were observed. Thus, our study proposes that SNAP-25b in pancreatic [beta] cells, except for participating in the core SNARE complex, is necessary for accurate regulation of Ca2+-dynamics.
Ključne besede
insulin secretion;pre-diabetes;
Podatki
Jezik: |
Angleški jezik |
Leto izida: |
2017 |
Tipologija: |
1.01 - Izvirni znanstveni članek |
Organizacija: |
UM MF - Medicinska fakulteta |
UDK: |
612.349.7 |
COBISS: |
512737080
|
ISSN: |
2045-2322 |
Št. ogledov: |
857 |
Št. prenosov: |
129 |
Ocena: |
0 (0 glasov) |
Metapodatki: |
|
Ostali podatki
Sekundarni jezik: |
Slovenski jezik |
Sekundarne ključne besede: |
Pancreas;physiology;Islets of Langerhans; |
URN: |
URN:SI:UM: |
Vrsta dela (COBISS): |
Znanstveno delo |
Strani: |
14 str. |
Zvezek: |
ǂVol. ǂ7 |
Čas izdaje: |
2017 |
DOI: |
10.1038/s41598-017-08082-y |
ID: |
10859897 |