Cortical mitochondria regulate insulin secretion by local Ca2+ buffering in rodent beta cells.
J Cell Sci
; 132(9)2019 04 30.
Article
em En
| MEDLINE
| ID: mdl-30926624
ABSTRACT
Mitochondria play an essential role in regulating insulin secretion from beta cells by providing the ATP needed for the membrane depolarization that results in voltage-dependent Ca2+ influx and subsequent insulin granule exocytosis. Ca2+, in turn, is also rapidly taken up by the mitochondria and exerts important feedback regulation of metabolism. The aim of this study was to determine whether the distribution of mitochondria within beta cells is important for the secretory capacity of these cells. We find that cortically localized mitochondria are abundant in rodent beta cells, and that these mitochondria redistribute towards the cell interior following depolarization. The redistribution requires Ca2+-induced remodeling of the cortical F-actin network. Using light-regulated motor proteins, we increased the cortical density of mitochondria twofold and found that this blunted the voltage-dependent increase in cytosolic Ca2+ concentration and suppressed insulin secretion. The activity-dependent changes in mitochondria distribution are likely to be important for the generation of Ca2+ microdomains required for efficient insulin granule release.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cálcio
/
Células Secretoras de Insulina
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Secreção de Insulina
/
Mitocôndrias
Limite:
Animals
Idioma:
En
Revista:
J Cell Sci
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Suécia