|
rdf:type |
|
|
lifeskim:mentions |
|
|
pubmed:dateCreated |
1998-5-21
|
|
pubmed:abstractText |
Microdomains of high Ca2+ concentration ([Ca2+]) may be critical to the control of intracellular processes such as secretion and metabolism without compromising other cell functions. To explore changes in [Ca2+] in the outer mantle (< 30 nm deep) that surrounds the surface of dense-core secretory granules, we have designed a recombinant chimaera between the granule protein phogrin and aequorin. When expressed in populations of insulin-secreting MIN6 or phaeochromocytoma PC12 cells, the chimaera was targeted to secretory granules as expected. The recombinant protein reported a similar [Ca2+] at the granule surface to that in the bulk cytosol, measured with untargeted aequorin. This was the case both at rest (-Ca2+- = 80-120 nM) and after stimulation with agents that provoke Ca2+ entry or Ca2+ mobilization from intracellular pools, and during activated secretion. Thus depolarization of MIN6 cell populations with high K+ increased [Ca2+] both in the bulk cytosol and close to the granules to approx. 4 microM, with near-identical kinetics of increase and recovery. Similarly, stimulation of PC12 cells with ATP provoked an increase in -Ca2+- in either domain to 1.3 microM. These data argue that, in MIN6 and PC12 neuroendocrine cells (i) significant mobilization of Ca2+ from most secretory granules probably does not occur during activated Ca2+ influx or mobilization of internal Ca2+ stores, and (ii) agonist-stimulated Ca2+-dependent secretion can occur without development of a large gradient of [Ca2+] between the surface of most secretory vesicles and the rest of the cytosol.
|
|
pubmed:grant |
|
|
pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-1517243,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-2163307,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-3858813,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-6094537,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-6117094,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-6204995,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-6344863,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7021800,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7482794,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7515895,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7730373,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7834745,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7914371,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7954659,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-7969419,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8052313,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8163544,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8226749,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8316857,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8592464,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8606773,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8608601,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8643602,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-8663434,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-9010210,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-9083036,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-9130702,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-9180077,
http://linkedlifedata.com/resource/pubmed/commentcorrection/9494112-9242406
|
|
pubmed:language |
eng
|
|
pubmed:journal |
|
|
pubmed:citationSubset |
IM
|
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenosine Triphosphate,
http://linkedlifedata.com/resource/pubmed/chemical/Aequorin,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Insulin,
http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins,
http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Neoplasm Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/PTPRN2 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium,
http://linkedlifedata.com/resource/pubmed/chemical/Protein Tyrosine Phosphatases,
http://linkedlifedata.com/resource/pubmed/chemical/Receptor-Like Protein Tyrosine...,
http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Fusion Proteins
|
|
pubmed:status |
MEDLINE
|
|
pubmed:month |
Mar
|
|
pubmed:issn |
0264-6021
|
|
pubmed:author |
|
|
pubmed:issnType |
Print
|
|
pubmed:day |
15
|
|
pubmed:volume |
330 ( Pt 3)
|
|
pubmed:owner |
NLM
|
|
pubmed:authorsComplete |
Y
|
|
pubmed:pagination |
1399-404
|
|
pubmed:dateRevised |
2011-11-17
|
|
pubmed:meshHeading |
pubmed-meshheading:9494112-Adenosine Triphosphate,
pubmed-meshheading:9494112-Aequorin,
pubmed-meshheading:9494112-Animals,
pubmed-meshheading:9494112-Calcium,
pubmed-meshheading:9494112-Cell Line,
pubmed-meshheading:9494112-Cytoplasmic Granules,
pubmed-meshheading:9494112-Insulin,
pubmed-meshheading:9494112-Islets of Langerhans,
pubmed-meshheading:9494112-Kinetics,
pubmed-meshheading:9494112-Luminescent Measurements,
pubmed-meshheading:9494112-Membrane Glycoproteins,
pubmed-meshheading:9494112-Membrane Proteins,
pubmed-meshheading:9494112-Neoplasm Proteins,
pubmed-meshheading:9494112-PC12 Cells,
pubmed-meshheading:9494112-Potassium,
pubmed-meshheading:9494112-Protein Tyrosine Phosphatases,
pubmed-meshheading:9494112-Rats,
pubmed-meshheading:9494112-Receptor-Like Protein Tyrosine Phosphatases, Class 8,
pubmed-meshheading:9494112-Recombinant Fusion Proteins,
pubmed-meshheading:9494112-Transfection
|
|
pubmed:year |
1998
|
|
pubmed:articleTitle |
A phogrin-aequorin chimaera to image free Ca2+ in the vicinity of secretory granules.
|
|
pubmed:affiliation |
Department of Biochemistry, School of Medical Sciences, University Walk, University of Bristol, Bristol BS8 1TD, U.K.
|
|
pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|
