Linked Life Data

10747966

Source:http://linkedlifedata.com/resource/pubmed/id/10747966

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2000-7-20
pubmed:abstractText
Kinetically distinct steps can be distinguished in the secretory response from neuroendocrine cells with slow ATP-dependent priming steps preceding the triggering of exocytosis by Ca(2+). One of these priming steps involves the maintenance of phosphatidylinositol 4, 5-bisphosphate (PtdIns-4,5-P(2)) through lipid kinases and is responsible for at least 70% of the ATP-dependent secretion observed in digitonin-permeabilized chromaffin cells. PtdIns-4,5-P(2) is usually thought to reside on the plasma membrane. However, because phosphatidylinositol 4-kinase is an integral chromaffin granule membrane protein, PtdIns-4,5-P(2) important in exocytosis may reside on the chromaffin granule membrane. In the present study we have investigated the localization of PtdIns-4,5-P(2) that is involved in exocytosis by transiently expressing in chromaffin cells a pleckstrin homology (PH) domain that specifically binds PtdIns-4, 5-P(2) and is fused to green fluorescent protein (GFP). The PH-GFP protein predominantly associated with the plasma membrane in chromaffin cells without any detectable association with chromaffin granules. Rhodamine-neomycin, which also binds to PtdIns-4,5-P(2), showed a similar subcellular localization. The transiently expressed PH-GFP inhibited exocytosis as measured by both biochemical and electrophysiological techniques. The results indicate that the inhibition was at a step after Ca(2+) entry and suggest that plasma membrane PtdIns-4,5-P(2) is important for exocytosis. Expression of PH-GFP also reduced calcium currents, raising the possibility that PtdIns-4,5-P(2) in some manner alters calcium channel function in chromaffin cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17878-85
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:10747966-Angiotensin II, pubmed-meshheading:10747966-Binding Sites, pubmed-meshheading:10747966-Cell Membrane, pubmed-meshheading:10747966-Chromaffin Cells, pubmed-meshheading:10747966-Chromaffin Granules, pubmed-meshheading:10747966-Dimethylphenylpiperazinium Iodide, pubmed-meshheading:10747966-Exocytosis, pubmed-meshheading:10747966-Genes, Reporter, pubmed-meshheading:10747966-Green Fluorescent Proteins, pubmed-meshheading:10747966-Human Growth Hormone, pubmed-meshheading:10747966-Humans, pubmed-meshheading:10747966-Kinetics, pubmed-meshheading:10747966-Luminescent Proteins, pubmed-meshheading:10747966-Phosphatidylinositol 4,5-Diphosphate, pubmed-meshheading:10747966-Phosphatidylinositol Phosphates, pubmed-meshheading:10747966-Recombinant Fusion Proteins, pubmed-meshheading:10747966-Transfection, pubmed-meshheading:10747966-src Homology Domains
pubmed:year
2000
pubmed:articleTitle
A pleckstrin homology domain specific for phosphatidylinositol 4, 5-bisphosphate (PtdIns-4,5-P2) and fused to green fluorescent protein identifies plasma membrane PtdIns-4,5-P2 as being important in exocytosis.
pubmed:affiliation
Department of Pharmacology, University of Michigan, Ann Arbor, Michigan 48109, USA. holz@umich.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.