TY - JOUR
T1 - GTP- and inositol 1,4,5-trisphosphate-activated intracellular calcium movements in neuronal and smooth muscle cell lines.
AU - Chueh, S. H.
AU - Mullaney, J. M.
AU - Ghosh, T. K.
AU - Zachary, A. L.
AU - Gill, D. L.
N1 - Copyright:
This record is sourced from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
PY - 1987/10/5
Y1 - 1987/10/5
N2 - Recent evidence has revealed that a highly sensitive and specific guanine nucleotide regulatory process controls intracellular Ca2+ release within N1E-115 neuroblastoma cells (Gill, D. L., Ueda, T., Chueh, S. H., and Noel, M. W. (1986) Nature 320, 461-464). The present report documents GTP-induced Ca2+ release within quite distinct cell types, including the DDT1MF-2 smooth muscle cell line. GTP-induced Ca2+ release has similar GTP sensitivity and specificity among cells and rapidly mobilizes up to 70% of Ca2+ specifically accumulated within a nonmitochondrial Ca2+-pumping organelle within permeabilized DDT2MF-2 cells. Maximal GTP-induced release of Ca2+ is observed to be greater than inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ release (the latter being approximately 30% of total releasable Ca2+). After maximal IP3-induced release, further IP3 addition is ineffective, whereas subsequent addition of GTP further releases Ca2+ to equal exactly the extent of Ca2+ release observed by addition of GTP in the absence of IP3. This suggests that IP3 releases Ca2+ from the same pool as GTP, whereas GTP also releases from an additional pool. The effects of GTP appear to be reversible since simple washing of GTP-treated cells restores their previous Ca2+ uptake properties. Electron microscopic analysis of GTP-treated membrane vesicles reveals their morphology to be unchanged, whereas treatment of vesicles with 3% polyethylene glycol, known to enhance GTP-mediated Ca2+ release, clearly induces close coalescence of membranes. In the presence of 4 mM oxalate, GTP induces a rapid and profound uptake, as opposed to release, of Ca2+. The findings suggest that GTP-activated Ca2+ movement is a widespread phenomenon among cells, which can function on the same Ca2+ pool mobilized by IP3, and although activating Ca2+ movement by a mechanism distinct from IP3, does so via a process that does not appear to involve fusion between membranes.
AB - Recent evidence has revealed that a highly sensitive and specific guanine nucleotide regulatory process controls intracellular Ca2+ release within N1E-115 neuroblastoma cells (Gill, D. L., Ueda, T., Chueh, S. H., and Noel, M. W. (1986) Nature 320, 461-464). The present report documents GTP-induced Ca2+ release within quite distinct cell types, including the DDT1MF-2 smooth muscle cell line. GTP-induced Ca2+ release has similar GTP sensitivity and specificity among cells and rapidly mobilizes up to 70% of Ca2+ specifically accumulated within a nonmitochondrial Ca2+-pumping organelle within permeabilized DDT2MF-2 cells. Maximal GTP-induced release of Ca2+ is observed to be greater than inositol 1,4,5-trisphosphate (IP3)-induced Ca2+ release (the latter being approximately 30% of total releasable Ca2+). After maximal IP3-induced release, further IP3 addition is ineffective, whereas subsequent addition of GTP further releases Ca2+ to equal exactly the extent of Ca2+ release observed by addition of GTP in the absence of IP3. This suggests that IP3 releases Ca2+ from the same pool as GTP, whereas GTP also releases from an additional pool. The effects of GTP appear to be reversible since simple washing of GTP-treated cells restores their previous Ca2+ uptake properties. Electron microscopic analysis of GTP-treated membrane vesicles reveals their morphology to be unchanged, whereas treatment of vesicles with 3% polyethylene glycol, known to enhance GTP-mediated Ca2+ release, clearly induces close coalescence of membranes. In the presence of 4 mM oxalate, GTP induces a rapid and profound uptake, as opposed to release, of Ca2+. The findings suggest that GTP-activated Ca2+ movement is a widespread phenomenon among cells, which can function on the same Ca2+ pool mobilized by IP3, and although activating Ca2+ movement by a mechanism distinct from IP3, does so via a process that does not appear to involve fusion between membranes.
UR - http://www.scopus.com/inward/record.url?scp=0023645641&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0023645641&partnerID=8YFLogxK
M3 - Article
C2 - 3498720
AN - SCOPUS:0023645641
SN - 0021-9258
VL - 262
SP - 13857
EP - 13864
JO - The Journal of biological chemistry
JF - The Journal of biological chemistry
IS - 28
ER -