Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2011-7-5
pubmed:abstractText
In pancreatic ?-cells, glucose-induced mitochondrial ATP production plays an important role in insulin secretion. The mitochondrial phosphate carrier PiC is a member of the SLC25 (solute carrier family 25) family and transports Pi from the cytosol into the mitochondrial matrix. Since intramitochondrial Pi is an essential substrate for mitochondrial ATP production by complex V (ATP synthase) and affects the activity of the respiratory chain, Pi transport via PiC may be a rate-limiting step for ATP production. We evaluated the role of PiC in metabolism-secretion coupling in pancreatic ?-cells using INS-1 cells manipulated to reduce PiC expression by siRNA (small interfering RNA). Consequent reduction of the PiC protein level decreased glucose (10 mM)-stimulated insulin secretion, the ATP:ADP ratio in the presence of 10 mM glucose and elevation of intracellular calcium concentration in response to 10 mM glucose without affecting the mitochondrial membrane potential (??m) in INS-1 cells. In experiments using the mitochondrial fraction of INS-1 cells in the presence of 1 mM succinate, PiC down-regulation decreased ATP production at various Pi concentrations ranging from 0.001 to 10 mM, but did not affect ??m at 3 mM Pi. In conclusion, the Pi supply to mitochondria via PiC plays a critical role in ATP production and metabolism-secretion coupling in INS-1 cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1470-8728
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
435
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
421-30
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:21265734-Animals, pubmed-meshheading:21265734-COS Cells, pubmed-meshheading:21265734-Cell Line, Tumor, pubmed-meshheading:21265734-Cercopithecus aethiops, pubmed-meshheading:21265734-Gene Expression Regulation, Neoplastic, pubmed-meshheading:21265734-Glucose, pubmed-meshheading:21265734-Insulin, pubmed-meshheading:21265734-Insulinoma, pubmed-meshheading:21265734-Metabolism, pubmed-meshheading:21265734-Mitochondrial Proteins, pubmed-meshheading:21265734-Pancreatic Neoplasms, pubmed-meshheading:21265734-Phosphate Transport Proteins, pubmed-meshheading:21265734-Phosphates, pubmed-meshheading:21265734-Proton-Phosphate Symporters, pubmed-meshheading:21265734-RNA, Small Interfering, pubmed-meshheading:21265734-Rats, pubmed-meshheading:21265734-Rats, Wistar, pubmed-meshheading:21265734-Secretory Pathway
pubmed:year
2011
pubmed:articleTitle
Role of mitochondrial phosphate carrier in metabolism-secretion coupling in rat insulinoma cell line INS-1.
pubmed:affiliation
Department of Diabetes and Clinical Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't