201
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Tharin S, Dziak E, Michalak M, Opas M. Widespread tissue distribution of rabbit calreticulin, a non-muscle functional analogue of calsequestrin. Cell Tissue Res 1992; 269:29-37. [PMID: 1423482 DOI: 10.1007/bf00384723] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Calreticulin was identified in a variety of rabbit tissues by Western blot analysis. Indirect immunofluorescence studies on cultured cells or frozen sections from the corresponding tissues revealed that the protein was distributed to the endoplasmic reticulum or sarcoplasmic reticulum. Calreticulin was found to be an abundant calcium-binding protein in non-muscle and smooth muscle cells and a constituent calcium-binding protein in cardiac and skeletal muscle. From the immunoblot data, calreticulin may exist as an isoform in rabbit neural retina. The present study establishes the ubiquity of calreticulin in intracellular calcium binding.
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Affiliation(s)
- S Tharin
- Department of Anatomy and Cell Biology, University of Toronto, Ontario, Canada
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202
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Villa A, Sharp AH, Racchetti G, Podini P, Bole DG, Dunn WA, Pozzan T, Snyder SH, Meldolesi J. The endoplasmic reticulum of Purkinje neuron body and dendrites: molecular identity and specializations for Ca2+ transport. Neuroscience 1992; 49:467-77. [PMID: 1331857 DOI: 10.1016/0306-4522(92)90111-e] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Immunofluorescence and immunogold labeling, together with sucrose gradient separation and Western blot analysis of microsomal subfractions, were employed in parallel to probe the endoplasmic reticulum in the cell body and dendrites of rat cerebellar Purkinje neurons. Two markers, previously investigated in non-nerve cells, the membrane protein p91 (calnexin) and the lumenal protein BiP, were found to be highly expressed and widely distributed to the various endoplasmic reticulum sections of Purkinje neurons, from the cell body to dendrites and dendritic spines. An antibody (denominated anti-rough-surfaced endoplasmic reticulum), which recognized two membrane proteins, p14 and p40, revealed a similar immunogold labeling pattern. However, centrifugation results consistent with a widespread distribution were obtained for p14 only, while p40 was concentrated in the rough microsome-enriched subfractions. The areas enriched in the inositol 1,4,5-triphosphate receptor and thus presumably specialized in Ca2+ transport (stacks of multiple smooth-surfaced cisternae; the dendritic spine apparatus) also exhibited labeling for BiP and p91, and were positive for the anti-rough-surfaced endoplasmic reticulum antibody (presumably via the p14 antigen). Additional antibodies, that yielded inadequate immunocytochemical signals, were employed only by Western blotting of the microsomal subfractions, while the ryanodine receptor was studied by specific binding. The latter receptor and the Ca2+ ATPase, known in other species to be concentrated in Purkinje neurons, exhibited bimodal distributions with a peak in the light and another in the heavy subfractions. A similar distribution was also observed with another lumenal protein, protein disulfide isomerase. Taken as a whole, the results that we have obtained suggest the existence in the endoplasmic reticulum of Purkinje neurons of two levels of organization; the first identified by widespread, probably general markers (BiP, p91, possibly p14 and others), the second by specialization markers, such as the inositol 1,4,5-triphosphate receptor and, possibly, p40, which appear restricted to areas where specific functions appear to be localized.
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Affiliation(s)
- A Villa
- Department of Pharmacology, CNR Cytopharmacology and B. Ceccarelli Centers, S. Raffaele Scientific Institute, Milano, Italy
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203
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The calcium pump of the liver nuclear membrane is identical to that of endoplasmic reticulum. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)49945-6] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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204
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Lodish H, Kong N, Wikström L. Calcium is required for folding of newly made subunits of the asialoglycoprotein receptor within the endoplasmic reticulum. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42340-x] [Citation(s) in RCA: 170] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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205
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Ross CA, Danoff SK, Schell MJ, Snyder SH, Ullrich A. Three additional inositol 1,4,5-trisphosphate receptors: molecular cloning and differential localization in brain and peripheral tissues. Proc Natl Acad Sci U S A 1992; 89:4265-9. [PMID: 1374893 PMCID: PMC49062 DOI: 10.1073/pnas.89.10.4265] [Citation(s) in RCA: 179] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Three inositol 1,4,5-trisphosphate receptor (IP3R) cDNAs, designated IP3R-II, -III, and -IV, were cloned from a mouse placenta cDNA library. All three display strong homology in membrane-spanning domains M7 and M8 to the originally cloned cerebellar IP3R-I, with divergences predominantly in cytoplasmic domains. Levels of mRNA for the three additional IP3Rs in general are substantially lower than for IP3R-I, though in the gastrointestinal tract the levels of IP3R-III may be comparable to IP3R-I. Cerebellar Purkinje cells express at least two and possibly three distinct IP3Rs, suggesting heterogeneity of IP3 action within a single cell.
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Affiliation(s)
- C A Ross
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2195
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206
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Affiliation(s)
- P Nicotera
- Department of Toxicology, Karolinska Institutet, Stockholm, Sweden
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207
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Preston SF, Berlin RD. An intracellular calcium store regulates protein synthesis in HeLa cells, but it is not the hormone-sensitive store. Cell Calcium 1992; 13:303-12. [PMID: 1377981 DOI: 10.1016/0143-4160(92)90065-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
There is considerable evidence, reviewed by Brostrom and Brostrom [1], that Ca2+ stores are involved in the regulation of protein synthesis. We provide evidence in HeLa cells that is consistent with their findings that depletion of Ca2+ stores and not changes in cytosolic free Ca2+ ([Ca2+]i) inhibit protein synthesis, but we also show that the mechanism leading to depletion is critical. Specifically, depletion of stores by the Ca(2+)-mobilizing hormone histamine does not inhibit protein synthesis. In assessing the role of Ca2+ stores in protein synthesis, experiments in certain cell types have been complicated by the use of Ca2+ ionophores, which simultaneously elevate [Ca2+]i and deplete Ca2+ stores. We have measured total cell Ca2+, [Ca2+]i and protein synthesis in HeLa cells under conditions that allowed evaluation of the separate contributions of stores and [Ca2+]i. Using 1,2-bis(2-aminophenoxyethane)-N,N,N'N'-tetraacetic acid (BAPTA) as an intracellular Ca2+, chelator and thapsigargin, which inhibits the membrane Ca(2+)-ATPase of storage vesicles, total cell Ca2+ can be depleted and this depletion is enhanced by extracellular EGTA which blocks Ca2+ influx; [Ca2+]i is actually lowered by BAPTA under these conditions. Protein synthesis is inhibited by BAPTA in the presence of EGTA and by thapsigargin with or without EGTA. However, histamine which with EGTA, affects an equal degree of Ca2+ depletion does not inhibit protein synthesis. Thus, it is suggested that Ca2+ stores are not homogeneous, and that the hormone-sensitive store specifically does not play a role in the regulation of protein synthesis. In this respect, the hormone-sensitive and insensitive stores do not functionally communicate and may be separately regulated.
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Affiliation(s)
- S F Preston
- Department of Physiology, University of Connecticut Health Center, Farmington
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208
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Lambert DG, Wojcikiewicz RJ, Safrany ST, Whitham EM, Nahorski SR. Muscarinic receptors, phosphoinositide metabolism and intracellular calcium in neuronal cells. Prog Neuropsychopharmacol Biol Psychiatry 1992; 16:253-70. [PMID: 1317042 DOI: 10.1016/0278-5846(92)90078-s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. We have utilised SH-SY5Y human neuroblastoma cells and primary cultures of rat neonatal cerebellar granule cells, both expressing M3 muscarinic receptors, to examine agonist driven polyphosphoinositide hydrolysis and alterations in intracellular calcium. 2. Stimulation of SH-SY5Y cells leads to a biphasic increase in intracellular calcium, the initial peak being due to the release of calcium from an intracellular store and the second maintained phase being due to calcium entry across the plasma membrane. The channel involved does not appear to be voltage sensitive, to involve a pertussis toxin sensitive G protein, or be opened by inositol polyphosphates. 3. Muscarinic receptor stimulation also leads to increased inositol polyphosphate formation in SH-SY5Y cells. Ins(1,4,5)P3 mass formation was biphasic in profile whereas Ins(1,3,4,5)P4 mass formation was slower and monophasic in profile. These data are consistent with substantial activity of 5-phosphatase (dephosphorylating Ins(1,4,5)P3 to Ins(1,4)P2) and 3-kinase (phosphorylating Ins(1,4,5)P3 to Ins(1,3,4,5)P4) in SH-SY5Y cells. 4. In order to better understand the role of Ins(1,4,5)P3 and its metabolites in calcium homeostasis we have examined the ability of a variety of natural and synthetic analogues to release intracellular sequestered calcium. The Ins(1,4,5)P3 calcium mobilizing receptor displays a remarkable degree of stereo- and positional selectivity with the most potent agonist to date being Ins(1,4,5)P3 (EC50 = 0.09 microM). 5. As an alternative to the continuous SH-SY5Y neuroblastoma (tumour derived) cell line we have used the primary cultured cerebellar granule cell. These cells also display a biphasic increase in Ins(1,4,5)P3 mass and a subsequent release of intracellular stored calcium. In our hands carbachol appears to increase calcium influx, a response which is only visible in the absence of magnesium.
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Affiliation(s)
- D G Lambert
- Department of Pharmacology and Therapeutics, University of Leicester, UK
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209
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Theibert A, Estevez V, Mourey R, Marecek J, Barrow R, Prestwich G, Snyder S. Photoaffinity labeling and characterization of isolated inositol 1,3,4,5-tetrakisphosphate- and inositol hexakisphosphate-binding proteins. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)50390-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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210
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Yamada M, Kakita A, Mizuguchi M, Rhee SG, Kim SU, Ikuta F. Ultrastructural localization of inositol 1,4,5-trisphosphate 3-kinase in rat cerebellar cortex. Brain Res 1992; 578:41-8. [PMID: 1324766 DOI: 10.1016/0006-8993(92)90227-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Subcellular localization of inositol 1,4,5-trisphosphate 3-kinase in the rat cerebellar cortex was studied immunohistochemically using a monoclonal antibody. Electron microscopy revealed intense immunoreactivity in the dendritic spines of Purkinje cells forming synapses with the parallel fibers, climbing fibers and recurrent collaterals of Purkinje cell axons. The labelling was associated with the hypolemmal cisternae, surrounding matrix and plasmalemma including the postsynaptic densities. Weaker immunoreactivity was present in the dendritic spines of basket cells and in certain segments of Purkinje cell recurrent collaterals. The postsynaptic regions of the dendritic trunks of Purkinje and basket cells were negative. These results indicate that inositol 1,4,5-trisphosphate 3-kinase is distributed amongst the spines of various synaptic relations with different electrophysiological properties, and that axon terminals of certain cell types are another functional site for the enzyme.
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Affiliation(s)
- M Yamada
- Department of Pathology, Niigata University, Japan
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211
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Sharp A, Snyder S, Nigam S. Inositol 1,4,5-trisphosphate receptors. Localization in epithelial tissue. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42537-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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212
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Ferris C, Cameron A, Bredt D, Huganir R, Snyder S. Autophosphorylation of inositol 1,4,5-trisphosphate receptors. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)50532-4] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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213
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Mechanism of Ca2+ inhibition of inositol 1,4,5-trisphosphate (InsP3) binding to the cerebellar InsP3 receptor. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)42538-0] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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214
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Khan AA, Steiner JP, Snyder SH. Plasma membrane inositol 1,4,5-trisphosphate receptor of lymphocytes: selective enrichment in sialic acid and unique binding specificity. Proc Natl Acad Sci U S A 1992; 89:2849-53. [PMID: 1313570 PMCID: PMC48760 DOI: 10.1073/pnas.89.7.2849] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The inositol 1,4,5-trisphosphate receptor (IP3R) associated with plasma membranes of lymphocytes differs in terminal sugar content and binding specificity from the cerebellar receptor, which is localized to endoplasmic reticulum. Lectin column chromatography reveals that 30% of IP3R in the thymus contains sialic acid, reflecting a plasma membrane association, in contrast to 5% of cerebellar IP3R. IP3R in thymus and plasma membrane fractions of Jurkat lymphocytes differs from IP3R of Jurkat microsomes and cerebellum in inositol phosphate specificity. The plasma membrane IP3R has lower affinity for IP3 but higher affinity for inositol 1,3,4,5-tetrakisphosphate, which may reflect a unique regulation of calcium at the plasma membrane by inositol phosphates.
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MESH Headings
- Animals
- Calcium Channels
- Cell Membrane/metabolism
- Cerebellum/metabolism
- Heparin/pharmacology
- Humans
- In Vitro Techniques
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Lymphocytes/chemistry
- Lymphocytes/metabolism
- Male
- Microsomes/metabolism
- Rats
- Rats, Inbred Strains
- Receptors, Cell Surface/chemistry
- Receptors, Cell Surface/metabolism
- Receptors, Cytoplasmic and Nuclear
- Receptors, Mitogen/chemistry
- Sialic Acids/analysis
- Thymus Gland/metabolism
- Tumor Cells, Cultured
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Affiliation(s)
- A A Khan
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205-2185
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215
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Mouillac B, Devilliers G, Jard S, Guillon G. Pharmacological characterization of inositol 1,4,5-trisphosphate binding sites: relation to Ca2+ release. Eur J Pharmacol 1992; 225:179-93. [PMID: 1516654 DOI: 10.1016/0922-4106(92)90019-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Two subcellular fractions, one enriched in plasma membranes and the other in endoplasmic reticulum membranes, were obtained from WRK1 cells using a combination of differential centrifugations and Percoll gradient fractionation. Specific inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) binding sites were detected in these two preparations. Endoplasmic reticulum membranes exhibited a binding capacity which was about 5-fold higher than that of plasma membranes. Dose-dependent Ins(1,4,5)P3 binding was determined. Experimental data obtained with endoplasmic reticulum membranes could be adequately fitted with a two-site model (a high-affinity binding site with Kd and Bmax values of 0.7 +/- 0.15 nM and 12.9 +/- 5 fmol/mg protein and a low-affinity binding site with Kd and Bmax values of 44.2 +/- 14.6 nM and 143 +/- 43 fmol/mg protein). Both the high- and low-affinity binding sites were selective for Ins(1,4,5)P3. Besides Ins(1,4,5)P3, Ins(1,3,4,5)P4 also discriminated between the two populations of sites while heparin interacted with the high- and low-affinity binding sites with the same affinity. Ins(1,4,5)P3-induced calcium release from endoplasmic reticulum vesicles was determined by monitoring the calcium concentration in the extravesicular compartment with fura-2. Under experimental conditions where the degradation of Ins(1,4,5)P3 was reduced (incubation at 0 degrees C), a high-affinity Ins(1,4,5)P3-induced calcium release (apparent Kact around 20 nM) could be demonstrated. These results suggest that in WRK1 cells, the endoplasmic reticulum is a major site for Ins(1,4,5)P3 action and that the high-affinity binding sites located on the endoplasmic reticulum membranes may contribute to the physiological regulation of the cytosolic free calcium concentration.
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Affiliation(s)
- B Mouillac
- Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France
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216
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Nagasawa H, Kogure K. Alterations of 45Ca accumulation and [3H]inositol 1,4,5-trisphosphate binding using autoradiography in the exo-focal postischemic brain areas of the rat. J Neurosci Res 1992; 31:507-12. [PMID: 1640501 DOI: 10.1002/jnr.490310314] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We studied the alterations of calcium accumulation and intracellular signal transduction using autoradiography of the second messenger system in order to clarify the mechanisms of the delayed neuronal changes in the remote areas of rat brain after transient focal ischemia. Chronological changes of 45Ca accumulation and [3H]inositol 1,4,5-trisphosphate (IP3) binding sites were determined after 90 min of right middle cerebral artery (MCA) occlusion and after such occlusion followed by different periods of recirculation. After the ischemic insult, 45Ca accumulation extended to the lateral segment of the caudate putamen and to the cerebral cortex, both supplied by the occluded MCA. One day after the ischemia, [3H]IP3 binding sites decreased significantly compared with the control values in these ischemic areas. Moreover, 3 days after the ischemia, 45Ca accumulation was first detected in the ipsilateral thalamus and the substantia nigra, which lay outside the ischemic areas. In the substantia nigra, a significant decrease of [3H]IP3 binding sites and concurrent 45Ca accumulation were observed. In the thalamus, however, there was not alteration until 1 week after the ischemia, and then [3H]IP3 binding sites increased significantly 2 weeks (P less than 0.05) and 4 weeks (P less than 0.01) after the ischemia. Based on the present study, we speculate that different mechanisms associated with signal transduction systems may be responsible for exo-focal postischemic delayed neuronal changes in the thalamus and the substantia nigra. The increase of [3H]IP3 binding sites of the thalamus in the chronic stage may be new evidence of plasticity related to neurotransmission.
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Affiliation(s)
- H Nagasawa
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
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217
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Authi KS. Localisation of the [32P]IP3 binding site on human platelet intracellular membranes isolated by high-voltage free-flow electrophoresis. FEBS Lett 1992; 298:173-6. [PMID: 1544439 DOI: 10.1016/0014-5793(92)80049-m] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This study reports the localisation of the [32P]IP3 binding site on highly purified membrane fractions prepared using high-voltage free-flow electrophoresis. Binding studies on mixed membranes, carried out at 4 degrees C, revealed a binding site with a Kd = 86 nM and beta max = 5.3 pmol/mg protein. The binding was potently inhibited by heparin. High-voltage free-flow electrophoresis was used to further purify surface and intracellular membranes. The intracellular membranes showed a 5-fold enrichment of binding sites with respect to the parent mixed membranes with the same Kd (80 nM), but the surface membranes showed an absence of binding activity. The results indicate the localisation of the IP3 receptor on highly purified intracellular membranes.
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Affiliation(s)
- K S Authi
- Platelet Section, Thrombosis Research Institute, Chelsea, London, UK
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218
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Feng L, Pereira B, Kraus-Friedmann N. Different localization of inositol 1,4,5-trisphosphate and ryanodine binding sites in rat liver. Cell Calcium 1992; 13:79-87. [PMID: 1321686 DOI: 10.1016/0143-4160(92)90001-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The distribution of inositol 1,4,5-trisphosphate and ryanodine binding sites between plasma membrane, microsomal, and mitochondrial fractions of rat liver were compared. IP3 bound mostly to the plasma membrane fraction (Kd = 6 nM; Bmax = 802 fmol/mg protein). Some IP3 binding sites were also present in the microsomal and mitochondrial fractions (Kd = 2.5 and 2.9 nM; Bmax = 35 and 23 fmol/mg protein respectively). The possibility that these binding sites are due to contamination of the fractions with plasma membrane cannot be excluded. Binding of IP3 to the plasma membrane was inhibited by heparin but not by either caffeine or tetracaine. High-affinity ryanodine binding sites were present mostly in the microsomal fraction (Kd = 13 nM; Bmax = 301 fmol/mg protein). Lower affinity binding sites were also found to be present in the mitochondrial and plasma membrane fractions. Binding of ryanodine to the microsomal fraction was inhibited by both caffeine and tetracaine but not by heparin. These data demonstrate that IP3 and ryanodine binding sites are present in different cellular compartments in the liver. These differences in the localization of the binding sites might be indicative of their functional differences.
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Affiliation(s)
- L Feng
- Department of Physiology and Cell Biology, University of Texas Medical School, Health Science Center, Houston
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219
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Van Delden C, Favre C, Spät A, Cerny E, Krause KH, Lew DP. Purification of an inositol 1,4,5-trisphosphate-binding calreticulin-containing intracellular compartment of HL-60 cells. Biochem J 1992; 281 ( Pt 3):651-6. [PMID: 1536644 PMCID: PMC1130739 DOI: 10.1042/bj2810651] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To investigate the identity of Ins(1,4,5)P3-sensitive intracellular Ca2+ stores in myeloid cells, we have developed a method that yields subcellular fractions highly enriched in Ins(1,4,5)P3 binding. HL-60 cells were disrupted by nitrogen cavitation, and subcellular fractions were obtained by differential centrifugation, followed by Percoll- and sucrose-density-gradient separations. A subcellular fraction enriched 26-fold in Ins(1,4,5)P3-binding sites was obtained. This fraction showed no enrichment in plasma-membrane markers and only a comparatively moderate enrichment (7-fold) in endoplasmic-reticulum markers. The ratio between specific enrichment of Ins(1,4,5)P3 binding and endoplasmic-reticulum markers in the different fractions varied over 50-fold, from less than 0.1 to greater than 5. The purified Ins(1,4,5)P3-binding fraction was enriched to a similar extent (27-fold) in the putative intravesicular Ca(2+)-storage protein calreticulin. Our results favour the concept of a distinct Ins(1,4,5)P3-binding, calreticulin-containing compartment (i.e. the calciosome) in HL-60 cells.
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Affiliation(s)
- C Van Delden
- Division of Infectious Diseases, Geneva University Hospital, Switzerland
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220
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221
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Fisher SK, Heacock AM, Agranoff BW. Inositol lipids and signal transduction in the nervous system: an update. J Neurochem 1992; 58:18-38. [PMID: 1309233 DOI: 10.1111/j.1471-4159.1992.tb09273.x] [Citation(s) in RCA: 194] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- S K Fisher
- Department of Pharmacology, University of Michigan, Ann Arbor 48104-1687
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222
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Dulhunty AF. The voltage-activation of contraction in skeletal muscle. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1992; 57:181-223. [PMID: 1603939 DOI: 10.1016/0079-6107(92)90024-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- A F Dulhunty
- John Curtin School of Medical Research, Australian National University, Canberra City
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223
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Li PP, Vecil GG, Green MA, Warsh JJ. Inositol 1,4,5-trisphosphate receptor in developing and senescent rat cerebellum. Neurobiol Aging 1992; 13:89-92. [PMID: 1311805 DOI: 10.1016/0197-4580(92)90014-o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Numerous process associated with intracellular calcium homeostasis have previously been found to vary with age. To determine whether the binding sites for the calcium-mobilizing second messenger, inositol 1,4,5-trisphosphate (InsP3), also displays such variation, [3H]InsP3 binding was investigated in cerebellar or cerebral cortical membranes prepared from rats at different ages from birth up to 24 months of age. In the cerebellum, the InsP3 receptor density was very low during the first week after birth, increased markedly between days 8 and 28 and then reached an apparent plateau between 28 to 56 days of age. The InsP3 receptor binding affinity was comparable at different developmental stages. No age-related differences were found in InsP3 receptor density or affinity in the cerebral cortex of 3-, 6-, 9-, 12-, and 24-month-old rats. In the cerebellum, InsP3 receptor density but not affinity was significantly reduced in 24-month-old compared only to 3-month-old animals. Our data suggest that the changes in InsP3 receptor binding during early development might reflect the growth and maturation of neurons containing these receptors (i.e., Purkinje cells). Furthermore, the age-dependent reduction in InsP3 receptor density, together with the recent report of senescent changes in protein kinase C activity, indicate that disruption of phosphoinositide second messenger system may be of importance to the impairment of neuronal responsiveness and behavioral deficits observed with aging.
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Affiliation(s)
- P P Li
- Section of Biochemical Psychiatry, Clarke Institute of Psychiatry, University of Toronto, Ontario, Canada
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224
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Johnson RJ, Liu NG, Fishman JB, Dixon JD, Fine RE. Isolation of a calreticulin-like calcium binding protein from bovine brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1992; 12:69-76. [PMID: 1312207 DOI: 10.1016/0169-328x(92)90069-n] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Intracellular calcium levels are stringently regulated in all cells. The nature of this regulation is incompletely understood, but recent evidence indicates that the endoplasmic reticulum plays an important role in sequestering intracellular calcium. Using methods for isolating both calsequestrin and calreticulin, we have isolated a 58 kDa, high capacity calcium binding protein that exists in microsomes that shift their density in an oxalate-mediated density shift assay. This protein which we call CBP-58 bears similarities to the endoplasmic reticulum protein, calreticulin, in that it has a pI of 4.7 containing approximately 30% glutamate and aspartate, has a high capacity for calcium, and stains blue with the carbocyanine dye, 'Stains-all'. Peptide, amino acid, nucleotide and immunochemical analyses reveal further similarities between CBP-58 and calreticulin, but also some marked differences. Its tissue distribution suggests it is highly enriched in brain versus other tissues. We believe that CBP-58 is a calreticulin-like protein and that differences in the amino acid composition and sequences may reflect species diversity in calreticulin.
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Affiliation(s)
- R J Johnson
- Anatomy and Neurobiology, Department, Boston University School of Medicine, MA 02118
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225
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Cocco L, Martelli AM, Gilmour RS, Rana RA, Barnabei O, Manzoli FA. Changes in inositol lipid metabolism and protein kinase C translocation in nuclei of mitogen stimulated Swiss 3T3 cells. ADVANCES IN ENZYME REGULATION 1992; 32:91-103. [PMID: 1323206 DOI: 10.1016/0065-2571(92)90010-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The correlation between changes in nuclear polyphosphoinositide levels preceding PKC translocation to the nucleus and the onset of DNA synthesis has been discussed. Using two different clones of Swiss 3T3 fibroblasts belonging to the same original cell line, one of which is unresponsive to mitogenic stimulation with IGF-I on its own or in combination with bombesin, it has been observed that a rapid and transient breakdown of nuclear PIP and PIP2 occurs only in responsive cells and this precedes the translocation of PKC to the nucleus, as evidenced by immunochemical analysis as well as by enzymatic activity. Therefore, it seems that a direct link exists between nuclear polyphosphoinositide metabolism, PKC translocation to the nucleus and cell division. Since IGF-I acts at the plasma membrane through a tyrosine kinase receptor it seems that the mitogenic stimulation induced by this factor utilizes different signalling pathways at the plasma membrane and at the nucleus. Because of the evidence that type I IGF receptor is expressed in both responsive and unresponsive cells and that the receptor machinery at the plasma membrane is active the lack of the transient changes in nuclear inositol lipids and of PKC translocation in unresponsive cells further suggests that the cell nucleus is capable of an autonomous signalling system based on polyphosphoinositide metabolism.
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Affiliation(s)
- L Cocco
- Institute of Human Anatomy, University of Bologna, Italy
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226
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Padua RA, Yamamoto T, Fyda D, Sawchuk MA, Geiger JD, Nagy JI. Autoradiographic analysis of [3H]Ryanodine binding sites in rat brain: regional distribution and the effects of lesions on sites in the hippocampus. J Chem Neuroanat 1992; 5:63-73. [PMID: 1605914 DOI: 10.1016/0891-0618(92)90034-n] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Quantitative and qualitative autoradiographic methods together with lesion approaches were used to determine the distribution of [3H]ryanodine binding sites in rat brain and the neuronal localization of these sites in the hippocampus. In normal animals, levels of [3H]ryanodine binding sites ranged from a low of about 1 fmol/mg tissue in subcortical structures to a high of 12-18 fmol/mg tissue in subregions of the hippocampus and the olfactory bulb. Relatively high densities of sites (5-9 fmol/mg tissue) were also seen in the olfactory tubercle, most areas of the cerebral cortex, accumbens nucleus, striatum, lateral septal nuclei, pontine nucleus, superior colliculus and granule cell layer of the cerebellum. Specific binding was undetectable in white matter. In experimental animals, intracerebral injections of kainic acid caused neuronal degeneration and a near total depletion of [3H]ryanodine binding sites in the dentate gyrus and in fields CA1, CA2 and CA3 of the hippocampus. Injections of kainic acid that left dentate granule cells largely intact while destroying all neurons in field CA3 had no effect on binding sites in the dentate gyrus. However, these lesions substantially reduced the density of binding in field CA3, leaving a narrow band of sites outlining the position of the degenerated CA3 pyramidal cells. Mechanical knife-cut lesions that severed the granule cell mossy fiber input to field CA3 reduced the density of binding sites in the CA3 region. The results indicate that [3H]ryanodine binding sites in brain are heterogeneously distributed and suggest that a proportion of these sites in the hippocampus may be contained in mossy fiber terminals where a presumptive calcium channel/ryanodine receptor complex may be involved in the regulation of calcium mobilization and/or neurotransmitter release.
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Affiliation(s)
- R A Padua
- Departments of Physiology, University of Manitoba, Faculty of Medicine, Winnipeg, Canada
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227
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Henzi V, MacDermott AB. Characteristics and function of Ca(2+)- and inositol 1,4,5-trisphosphate-releasable stores of Ca2+ in neurons. Neuroscience 1992; 46:251-73. [PMID: 1311812 DOI: 10.1016/0306-4522(92)90049-8] [Citation(s) in RCA: 210] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Molecular, biochemical and physiological evidence for the existence of releasable Ca2+ stores in neurons is strong. There are two separate molecules that function as release channels from those Ca2+ stores, the RyanR and InsP3R, and both have multiple regulatory sites for positive and negative control. Perhaps most intriguing is the biphasic, concentration-dependent action of cytosolic Ca2+ on both channels, first to stimulate release then, at higher concentration, to depress release. Whether the InsP3R and RyanR channels regulate Ca2+ release from different or identical functional compartments will need to be defined for each neuron type and perhaps even for each intracellular region within neurons since the evidence for functional separation of stores is mixed. The identification of Ca2+ storage and releasing capacity throughout all subcellular regions of neurons and the increasing evidence for a role for Ca2+ stores in neuronal plasticity suggests that the further characterization of the functional properties of Ca2+ stores will be an increasingly important and expanding area of interest in neurobiology.
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Affiliation(s)
- V Henzi
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032
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228
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Wilkin GP, Marriott DR, Cholewinski AJ, Wood JN, Taylor GW, Stephens GJ, Djamgoz MB. Receptor activation and its biochemical consequences in astrocytes. Ann N Y Acad Sci 1991; 633:475-88. [PMID: 1665035 DOI: 10.1111/j.1749-6632.1991.tb15637.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- G P Wilkin
- Department of Biochemistry, Imperial College of Science, Technology & Medicine, London, UK
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229
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Nagasawa H, Kogure K. Alterations of [3H]inositol 1,4,5-trisphosphate binding in the postischemic rat brain. Neurosci Lett 1991; 133:129-32. [PMID: 1791989 DOI: 10.1016/0304-3940(91)90074-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Chronological changes of [3H]inositol 1,4,5-trisphosphate (IP3) binding sites were determined after 90 min of right middle cerebral artery (MCA) occlusion and after such occlusion followed by different periods of recirculation. One day after the ischemia, [3H]IP3 binding sites decreased significantly compared with the control values in the lateral segment of the caudate putamen and the cerebral cortex, both supplied by the occluded MCA. Moreover, 3 days after the ischemia, a significant decrease of [3H]IP3 binding sites was observed in the substantia nigra of ischemic side. In the ipsilateral thalamus, however, there was no alteration until 1 week after the ischemia, and then [3H]IP3 binding sites increased significantly 2 weeks (P less than 0.05) and 4 weeks (P less than 0.01) after the ischemia. Based on the present study, we speculate that different mechanisms associated with signal transduction systems may be responsible for exo-focal postischemic delayed neuronal changes in the thalamus and the substantia nigra. The increase of [3H]IP3 binding sites of the thalamus in the chronic stage may be new evidence of plasticity related to neurotransmission.
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Affiliation(s)
- H Nagasawa
- Department of Neurology, Tohoku University School of Medicine, Sendai, Japan
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230
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Terasaki M, Sardet C. Demonstration of calcium uptake and release by sea urchin egg cortical endoplasmic reticulum. J Cell Biol 1991; 115:1031-7. [PMID: 1955454 PMCID: PMC2289945 DOI: 10.1083/jcb.115.4.1031] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The calcium indicator dye fluo-3/AM was loaded into the ER of isolated cortices of unfertilized eggs of the sea urchin Arbacia punctulata. Development of the fluorescent signal took from 8 to 40 min and usually required 1 mM ATP. The signal decreased to a minimum level within 30 s after perfusion with 1 microM InsP3 and increased within 5 min when InsP3 was replaced with 1 mM ATP. Also, the fluorescence signal was lowered rapidly by perfusion with 10 microM A23187 or 10 microM ionomycin. These findings demonstrate that the cortical ER is a site of ATP-dependent calcium sequestration and InsP3-induced calcium release. A light-induced wave of calcium release, traveling between 0.7 and 2.8 microns/s (average speed 1.4 microns/s, N = 8), was sometimes observed during time lapse recordings; it may therefore be possible to use the isolated cortex preparation to investigate the postfertilization calcium wave.
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Affiliation(s)
- M Terasaki
- Marine Biological Laboratories, Woods Hole, Massachusetts
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231
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Michalak M, Baksh S, Opas M. Identification and immunolocalization of calreticulin in pancreatic cells: no evidence for "calciosomes". Exp Cell Res 1991; 197:91-9. [PMID: 1915668 DOI: 10.1016/0014-4827(91)90484-c] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the present study, we have shown that calreticulin is a major Ca(2+)-sequestering protein in pancreatic microsomes. This protein is a peripheral membrane protein and could be extracted from the microsomal membrane with carbonate buffer at pH 11.4. Calreticulin was identified in the membrane fractions by immunoblotting with a specific antibody, by a 45Ca2+ overlay technique, and by NH2-terminal amino acid analysis of the purified protein. Immunocytochemical localization of calreticulin in pancreatic acinar cells and pancreatic fibroblasts showed that the protein is localized to the ER membranes in these cells. We were unable to detect calsequestrin or any calsequestrin-like proteins in the pancreas and found no evidence for the existence of large numbers of specialized, calreticulin-containing vesicles which could be an equivalent of the calsequestrin-containing calciosomes previously reported in this tissue. Purified pancreatic calreticulin binds Ca2+ with both a low and a high capacity (approximately 1 mol of Ca2+/mol of protein and approximately 20-23 mol of Ca2+/mol of protein). The concentrations of Ca2+ required for half-maximal saturation of the low and high capacity sites were approximately 4-6 microM and approximately 1.5 mM, respectively. We conclude that calreticulin, which is confined to the lumen of the ER, plays a major role in Ca2+ storage in pancreatic cells.
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Affiliation(s)
- M Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Canada
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232
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Zimanyi I, Pessah IN. Pharmacological characterization of the specific binding of [3H]ryanodine to rat brain microsomal membranes. Brain Res 1991; 561:181-91. [PMID: 1666327 DOI: 10.1016/0006-8993(91)91594-q] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
High-affinity binding of [3H]ryanodine has been characterized in rat brain microsomal fractions. Membrane fractions from 4 brain regions (cerebral cortex, cerebellum, hippocampus and brainstem) have been isolated using sucrose density gradient purification. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed the presence of a high-molecular weight protein (Mr approximately 320 kDa), similar to that of ryanodine receptor from muscle sarcoplasmic reticulum (SR). In the presence of high salt (1 M KCl), [3H]ryanodine binds to low density (0.8 M sucrose) cortical microsomal fraction with high affinity (Kd 1.5 nM), and with the highest capacity (Bmax 330 fmol/mg protein). Kinetic analysis of the binding suggests multiple available binding sites for ryanodine. Binding of ryanodine is Ca2+ dependent (ED50 1 microM) and inhibited by Mg2+ and Ruthenium red. Adenine nucleotides have a biphasic effect on the binding of [3H]ryanodine. At low Ca2+ concentration caffeine and daunorubicin enhance the binding of [3H]ryanodine. The inositol 1,4,5-trisphosphate (IP3) binding inhibitor, heparin, has no effect on ryanodine binding, and ryanodine and caffeine do not influence the binding of [3H]IP3, which is enriched in the cerebellar fractions. These data demonstrate significant quantitative differences in the pharmacology of brain and muscle receptors and raise the question as to the physiological role of ryanodine binding proteins in the central nervous system and whether it is coupled to an endoplasmatic reticulum (ER) Ca2+ release channel.
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MESH Headings
- Adenosine Triphosphatases/metabolism
- Animals
- Brain/metabolism
- Calcium/pharmacology
- Calcium Channels
- Cell Fractionation
- Centrifugation, Density Gradient
- Electrophoresis, Polyacrylamide Gel
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Intracellular Membranes/metabolism
- Kinetics
- Magnesium/pharmacology
- Microsomes/metabolism
- Molecular Weight
- Organ Specificity
- Rats
- Rats, Inbred Strains
- Receptors, Cell Surface/metabolism
- Receptors, Cholinergic/drug effects
- Receptors, Cholinergic/isolation & purification
- Receptors, Cholinergic/metabolism
- Receptors, Cytoplasmic and Nuclear
- Ryanodine/metabolism
- Ryanodine Receptor Calcium Release Channel
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Affiliation(s)
- I Zimanyi
- Department of Veterinary Pharmacology and Toxicology, University of California, Davis 95616
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233
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Relationship between agonist- and thapsigargin-sensitive calcium pools in adrenal glomerulosa cells. Thapsigargin-induced Ca2+ mobilization and entry. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)55110-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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234
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Hansen C, Yang L, Williamson J. Mechanisms of receptor-mediated Ca2+ signaling in rat hepatocytes. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)55101-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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235
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Llano I, Dreessen J, Kano M, Konnerth A. Intradendritic release of calcium induced by glutamate in cerebellar Purkinje cells. Neuron 1991; 7:577-83. [PMID: 1681831 DOI: 10.1016/0896-6273(91)90370-f] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The ability of excitatory amino acids to induce increases in the intracellular Ca2+ concentration ([Ca2+]i) of cerebellar Purkinje cells was examined by digital fluorescence ratio imaging of voltage-clamped Purkinje cells dialyzed with the Ca2+ indicator fura-2. Purkinje cells responded with large inward currents accompanied by increases in dendritic [Ca2+]i when challenged with the excitatory amino acid agonists glutamate and quisqualate. The rise in [Ca2+]i was transient and reached peak values of several hundred nanomolar. The response subsisted in the absence of extracellular Ca2+, a condition that eliminates Ca2+ entry through voltage-gated Ca2+ channels, indicating that Ca2+ arose in large part from an intracellular compartment. In support of this hypothesis, only the first agonist application elicited a [Ca2+]i increase in slices maintained in Ca(2+)-free medium, as expected if the intracellular stores become depleted. These results indicate that metabotropic glutamate receptors are functional in Purkinje cells and point to glutamate as a possible modulator of [Ca2+]i in these neurons.
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Affiliation(s)
- I Llano
- Laboratoire de Neurobiologie, Ecole Normale Supérieure, Paris, France
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236
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Affiliation(s)
- R D Burgoyne
- Department of Physiology, University of Liverpool, UK
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237
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Whitham EM, Challiss RA, Nahorski SR. Inositol 1,4,5-triphosphate-stimulated calcium release from permeabilized cerebellar granule cells. Br J Pharmacol 1991; 104:202-6. [PMID: 1786511 PMCID: PMC1908263 DOI: 10.1111/j.1476-5381.1991.tb12408.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
1. Muscarinic cholinoceptor stimulation of phosphoinositide hydrolysis in rat cultured cerebellar granule cells results in a rapid, transient accumulation of inositol 1,4,5-trisphosphate (Ins(1,4,5)P3), which has been implicated in the release of non-mitochondrial intracellular Ca2+ stores. In the present study, the release of Ca2+ from intracellular stores and the Ins(1,4,5)P3 receptor responsible for this process have been investigated. 2. Monolayers of saponin-permeabilized granule cells accumulate 45Ca2+ in an ATP-dependent manner and the sequestered 45Ca2+ can be concentration-dependently released by Ins(1,4,5)P3 by a stereospecific and heparin-sensitive mechanism. The EC50 for Ins(1,4,5)P3-stimulated 45Ca2+ release was 80 +/- 3 nM. 3. Radioligand binding studies performed on a crude granule cell membrane fraction indicated the presence of an apparently homogeneous population of stereo-specific Ins(1,4,5)P3 receptors (KD 54.7 +/- 2.0 nM; Bmax 1.37 +/- 0.29 pmol mg-1 protein). 4. This study provides evidence for Ins(1,4,5)P3-sensitive intracellular Ca2+ stores in primary cultures of cerebellar granule cells and suggest that these cells provide an excellent model neuronal system in which to study the relative functional roles of Ca2+ release from intracellular stores and Ca(2+)-entry in neuronal Ca2+ homeostasis.
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Affiliation(s)
- E M Whitham
- Department of Pharmacology and Therapeutics, University of Leicester
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238
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Terasaki M, Jaffe LA. Organization of the sea urchin egg endoplasmic reticulum and its reorganization at fertilization. J Cell Biol 1991; 114:929-40. [PMID: 1874789 PMCID: PMC2289104 DOI: 10.1083/jcb.114.5.929] [Citation(s) in RCA: 188] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The ER of eggs of the sea urchin Lytechinus pictus was stained by microinjecting a saturated solution of the fluorescent dicarbocyanine DiIC18(3) (DiI) in soybean oil; the dye spread from the oil drop into ER membranes throughout the egg but not into other organelles. Confocal microscopy revealed large cisternae extending throughout the interior of the egg and a tubular membrane network at the cortex. Since diffusion of DiI is confined to continuous bilayers, the spread of the dye supports the concept that the ER is a cell-wide, interconnected compartment. In time lapse observations, the internal cisternae were seen to be in continuous motion, while the cortical ER was stationary. After fertilization, the internal ER appeared to become more finely divided, beginning as a wave apparently coincident with the calcium wave and becoming most marked by 2-3 min. By 5-8 min the ER returned to an organization similar to that of the unfertilized egg. The cortical network also changed at fertilization; it became disrupted and eventually recovered. DiI labeling allowed continuous observations of the ER during pronuclear migration and mitosis. DiI-stained membranes accumulated in the region of the microtubule array surrounding the sperm nucleus and centriole (the sperm aster) as it migrated to the center of the egg; this accumulation persisted near the centrosomes and zygote nucleus throughout pronuclear fusion and the first two mitotic cycles. We have used a new method to observe the spatial and temporal organization of the ER in a living cell, and we have demonstrated a striking reorganization of the ER at fertilization.
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Affiliation(s)
- M Terasaki
- Laboratory of Neurobiology, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892
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239
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Li PP, Green MA, Warsh JJ. A study of cerebellar inositol 1,4,5-trisphosphate receptor following climbing and parallel fibre deafferentation. Brain Res 1991; 555:169-72. [PMID: 1657296 DOI: 10.1016/0006-8993(91)90875-v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have examined the influence of climbing fibre and parallel fibre afferent inputs on the inositol 1,4,5-trisphosphate (InsP3) receptor in rat cerebellum. Lesions of the inferior olive-climbing fibre projections to Purkinje cells by 3-acetylpyridine (3-AP) significantly reduced the [3H]InsP3 binding density (-20%) with no apparent changes in the binding affinity 21 days after treatment. No further reduction in binding density was found in rats given a second dose 7 days after the initial injection. A significant reduction in the binding density was evident as early as 7 days post-lesion. However, 3-AP (0.5 mM) failed to inhibit [3H]InsP3 binding in vitro. Cerebellar granule cells were lesioned by two consecutive injections of methylazoxymethanol acetate at birth. In these 60-day-old granuloprival rats, the density and affinity of [3H]InsP3 binding sites in the cerebellum remained comparable to the controls. Since lesions of the climbing fibres increase Purkinje cell activity, we suggest that changes in InsP3 receptor density may reflect an adaptative response to the heightened Purkinje cell activity. In addition, the results also indicate that expression of the InsP3 receptor in the cerebellum is largely independent of the presence of granule cell-parallel fibre synaptic innervation onto the Purkinje cells.
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Affiliation(s)
- P P Li
- Section of Biochemical Psychiatry, Clarke Institute of Psychiatry, Toronto, Ont., Canada
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240
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Nakagawa T, Okano H, Furuichi T, Aruga J, Mikoshiba K. The subtypes of the mouse inositol 1,4,5-trisphosphate receptor are expressed in a tissue-specific and developmentally specific manner. Proc Natl Acad Sci U S A 1991; 88:6244-8. [PMID: 1648733 PMCID: PMC52059 DOI: 10.1073/pnas.88.14.6244] [Citation(s) in RCA: 188] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Additional subtypes of the inositol 1,4,5-trisphosphate (InsP3) receptor are expressed in a tissue-specific and developmentally specific manner. They differ from the InsP3 receptor structure previously reported in two small variably spliced segments. One segment (SI) is located within the InsP3 binding site, whereas another segment (SII) is located near putative sites for phosphorylation and ATP binding to modulate InsP3 action on Ca2+ flux. Therefore, we speculate that selective use of InsP3 receptor subtypes permits a tissue-specific and developmentally specific expression of functionally distinct channels.
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MESH Headings
- Aging/physiology
- Amino Acid Sequence
- Animals
- Base Sequence
- Brain/growth & development
- Calcium Channels
- DNA/genetics
- DNA/isolation & purification
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Male
- Mice
- Mice, Inbred ICR
- Molecular Sequence Data
- Organ Specificity
- Polymerase Chain Reaction/methods
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Cytoplasmic and Nuclear
- Restriction Mapping
- Spinal Cord/growth & development
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Affiliation(s)
- T Nakagawa
- Division of Regulation of Macromolecular Function, Osaka University, Suita, Japan
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241
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Fuller CM, Benos DJ. The physiology and biochemistry of sodium and chloride permeability pathways in epithelia. J Nutr Biochem 1991. [DOI: 10.1016/0955-2863(91)90091-i] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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242
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Rossier MF, Putney JW. The identity of the calcium-storing, inositol 1,4,5-trisphosphate-sensitive organelle in non-muscle cells: calciosome, endoplasmic reticulum ... or both? Trends Neurosci 1991; 14:310-4. [PMID: 1719679 DOI: 10.1016/0166-2236(91)90143-i] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Although the initial phase of receptor-mediated Ca2+ signaling, involving Ca2+ release from intracellular stores by inositol 1,4,5-trisphosphate, is relatively well characterized, the nature of the organelle releasing Ca2+ is a controversial subject. At issue is the question of whether Ca2+ is released from the endoplasmic reticulum, or from a more specialized organelle called the 'calciosome'. In this review, we attempt to analyse the arguments for and against these two views, and attempt to reconcile some of the apparently conflicting findings by proposing a hypothetical model of the inositol 1,4,5-trisphosphate-sensitive Ca2+ pool.
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Affiliation(s)
- M F Rossier
- Laboratory of Cellular and Molecular Pharmacology, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709
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243
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Abstract
Chloride-selective ion channels were measured from isolated rat liver nuclei. Single ion channel currents were recorded in both "nuclear-attached" and in excised patches in the inside-out configuration of the patch-clamp technique. Two types of chloride conductance were defined, a large conductance (150 pS; iCl,N) channel with complex kinetics and multiple substates, and a second smaller conductance (58 pS;ICln) channel sensitive to block by ATP. The channels were inhibited by pharmacological agents known to block chloride channels and were insensitive to internal and external changes in calcium and magnesium. Presumably the channels reside in the external membrane of the nuclear double membrane and may mediate charge balance in the release and uptake of calcium from the perinuclear space.
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Affiliation(s)
- L Tabares
- Department of Pharmacology, Mayo Foundation, Rochester, Minnesota 55905
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244
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245
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Bezprozvanny I, Watras J, Ehrlich BE. Bell-shaped calcium-response curves of Ins(1,4,5)P3- and calcium-gated channels from endoplasmic reticulum of cerebellum. Nature 1991; 351:751-4. [PMID: 1648178 DOI: 10.1038/351751a0] [Citation(s) in RCA: 1350] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Release of calcium from intracellular stores occurs by two pathways, an inositol 1,4,5-trisphosphate (InsP3)-gated channel and a calcium-gated channel (ryanodine receptor). Using specific antibodies, both receptors were found in Purkinje cells of cerebellum. We have now compared the functional properties of the channels corresponding to the two receptors by incorporating endoplasmic reticulum vesicles from canine cerebellum into planar bilayers. InsP3-gated channels were observed most frequently. Another channel type was activated by adenine nucleotides or caffeine, inhibited by ruthenium red, and modified by ryanodine, characteristics of the ryanodine receptor/channel6. The open probability of both channel types displayed a bell-shaped curve for dependence on calcium. For the InsP3-gated channel, the maximum probability of opening occurred at 0.2 microM free calcium, with sharp decreases on either side of the maximum. Maximum activity for the ryanodine receptor/channel was maintained between 1 and 100 microM calcium. Thus, within the physiological range of cytoplasmic calcium, the InsP3-gated channel itself allows positive feedback and then negative feedback for calcium release, whereas the ryanodine receptor/channel behaves solely as a calcium-activated channel. The existence in the same cell of two channels with different responses to calcium and different ligand sensitivities provides a basis for complex patterns of intracellular calcium regulation.
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Affiliation(s)
- I Bezprozvanny
- Department of Medicine, University of Connecticut, Health Center, Farmington 06032
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246
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Rossi A, Manzo L, Orrenius S, Vahter M, Nicotera P. Modifications of cell signalling in the cytotoxicity of metals. PHARMACOLOGY & TOXICOLOGY 1991; 68:424-9. [PMID: 1653953 DOI: 10.1111/j.1600-0773.1991.tb01265.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Many metals act on biological systems at low concentrations and recent epidemiological and experimental research indicates that toxic effects of certain metals occur at levels only marginally higher than those found in healthy subjects. Despite a large number of studies describing metal cytotoxicity, the molecular mechanisms involved are still poorly understood. However, it now seems evident that several metals can interact with enzyme functional groups and that proteins involved in signal transduction, including Ca2+ channels and pumps, may be especially sensitive to this interaction. Impairment of the ability of cells to adequately respond to the stimulation by hormones and growth factors may result in the loss of important cell functions or activation of mechanisms that compromise cell survival. In the following sections we will briefly describe the effects of various metals on cell signalling and present our recent findings on the mechanism by which inorganic mercury affects signal transduction.
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Affiliation(s)
- A Rossi
- Institute of Environmental Medicine, Karolinska Institutet. Stockholm, Sweden
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247
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Walton PD, Airey JA, Sutko JL, Beck CF, Mignery GA, Südhof TC, Deerinck TJ, Ellisman MH. Ryanodine and inositol trisphosphate receptors coexist in avian cerebellar Purkinje neurons. J Biophys Biochem Cytol 1991; 113:1145-57. [PMID: 1645737 PMCID: PMC2289007 DOI: 10.1083/jcb.113.5.1145] [Citation(s) in RCA: 219] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Two intracellular calcium-release channel proteins, the inositol trisphosphate (InsP3), and ryanodine receptors, have been identified in mammalian and avian cerebellar Purkinje neurons. In the present study, biochemical and immunological techniques were used to demonstrate that these proteins coexist in the same avian Purkinje neurons, where they have different intracellular distributions. Western analyses demonstrate that antibodies produced against the InsP3 and the ryanodine receptors do not cross-react. Based on their relative rates of sedimentation in continuous sucrose gradients and SDS-PAGE, the avian cerebellar InsP3 receptor has apparent native and subunit molecular weights of approximately 1,000 and 260 kD, while those of the ryanodine receptors are approximately 2,000 and 500 kD. Specific [3H]InsP3- and [3H]ryanodine-binding activities were localized in the sucrose gradient fractions enriched in the 260-kD and the approximately 500-kD polypeptides, respectively. Under equilibrium conditions, cerebellar microsomes bound [3H]InsP3 with a Kd of 16.8 nM and Bmax of 3.8 pmol/mg protein; whereas, [3H]ryanodine was bound with a Kd of 1.5 nM and a capacity of 0.08 pmol/mg protein. Immunolocalization techniques, applied at both the light and electron microscopic levels, revealed that the InsP3 and ryanodine receptors have overlapping, yet distinctive intracellular distributions in avian Purkinje neurons. Most notably the InsP3 receptor is localized in endomembranes of the dendritic tree, in both the shafts and spines. In contrast, the ryanodine receptor is observed in dendritic shafts, but not in the spines. Both receptors appear to be more abundant at main branch points of the dendritic arbor. In Purkinje neuron cell bodies, both the InsP3 and ryanodine receptors are present in smooth and rough ER, subsurface membrane cisternae and to a lesser extent in the nuclear envelope. In some cases the receptors coexist in the same membranes. Neither protein is observed at the plasma membrane, Golgi complex or mitochondrial membranes. Both the InsP3 and ryanodine receptors are associated with intracellular membrane systems in axonal processes, although they are less abundant there than in dendrites. These data demonstrate that InsP3 and ryanodine receptors exist as unique proteins in the same Purkinje neuron. These calcium-release channels appear to coexist in ER membranes in most regions of the Purkinje neurons, but importantly they are differentially distributed in dendritic processes, with the dendritic spines containing only InsP3 receptors.
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MESH Headings
- Animals
- Antibodies, Monoclonal
- Blotting, Western
- Calcium Channels
- Cell Membrane/ultrastructure
- Chickens
- Electrophoresis, Polyacrylamide Gel
- Endoplasmic Reticulum/metabolism
- Endoplasmic Reticulum/ultrastructure
- Fluorescent Antibody Technique
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Microscopy, Immunoelectron
- Microsomes/metabolism
- Microsomes/ultrastructure
- Molecular Weight
- Purkinje Cells/cytology
- Purkinje Cells/metabolism
- Purkinje Cells/ultrastructure
- Receptors, Cell Surface/analysis
- Receptors, Cell Surface/isolation & purification
- Receptors, Cell Surface/metabolism
- Receptors, Cholinergic/analysis
- Receptors, Cholinergic/isolation & purification
- Receptors, Cholinergic/metabolism
- Receptors, Cytoplasmic and Nuclear
- Ryanodine/metabolism
- Ryanodine Receptor Calcium Release Channel
- Tritium
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Affiliation(s)
- P D Walton
- Department of Pharmacology, University of Nevada, Reno 89557
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248
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Villa A, Podini P, Clegg DO, Pozzan T, Meldolesi J. Intracellular Ca2+ stores in chicken Purkinje neurons: differential distribution of the low affinity-high capacity Ca2+ binding protein, calsequestrin, of Ca2+ ATPase and of the ER lumenal protein, Bip. J Cell Biol 1991; 113:779-91. [PMID: 1827445 PMCID: PMC2288980 DOI: 10.1083/jcb.113.4.779] [Citation(s) in RCA: 140] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
To identify intracellular Ca2+ stores, we have mapped (by cryosection immunofluorescence and immunogold labeling) the distribution in the chicken cerebellar cortex of an essential component, the main low affinity-high capacity Ca2+ binding protein which in this tissue has been recently shown undistinguishable from muscle calsequestrin (Volpe, P., B. H. Alderson-Lang, L. Madeddu, E. Damiani, J. H. Collins, and A. Margreth. 1990. Neuron. 5:713-721). Appreciable levels of the protein were found exclusively within Purkinje neurons, distributed to the cell body, the axon, and the elaborate dendritic tree, with little labeling, however, of dendritic spines. At the EM level the protein displayed a dual localization: within the ER (rough- and smooth-surfaced cisternae, including the cisternal stacks recently shown [in the rat] to be highly enriched in receptors for inositol 1,4,5-triphosphate) and, over 10-fold more concentrated, within a population of moderately dense, membrane-bound small vacuoles and tubules, identified as calciosomes. These latter structures were widely distributed both in the cell body (approximately 1% of the cross-sectional area, particularly concentrated near the Golgi complex) and in the dendrites, up to the entrance of the spines. The distribution of calsequestrin was compared to those of another putative component of the Ca2+ stores, the membrane pump Ca2+ ATPase, and of the ER resident lumenal protein, Bip. Ca2+ ATPase was expressed by both calciosomes and regular ER cisternae, but excluded from cisternal stacks; Bip was abundant within the ER lumena (cisternae and stacks) and very low within calciosomes (average calsequestrin/Bip immunolabeling ratios were approximately 0.5 and 36.5 in the two types of structure, respectively). These results suggest that ER cisternal stacks do not represent independent Ca2+ stores, but operate coordinately with the adjacent, lumenally continuous ER cisternae. The ER and calciosomes could serve as rapidly exchanging Ca2+ stores, characterized however by different properties, in particular, by the greater Ca2+ accumulation potential of calciosomes. Hypotheses of calciosome biogenesis (directly from the ER or via the Golgi complex) are discussed.
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Affiliation(s)
- A Villa
- Department of Pharmacology, Consiglio Nazionale delle Ricerche Cytopharmacology, University of Milano, Italy
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249
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Michelangeli F, Di Virgilio F, Villa A, Podini P, Meldolesi J, Pozzan T. Identification, kinetic properties and intracellular localization of the (Ca(2+)-Mg2+)-ATPase from the intracellular stores of chicken cerebellum. Biochem J 1991; 275 ( Pt 3):555-61. [PMID: 1828146 PMCID: PMC1150202 DOI: 10.1042/bj2750555] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The microsomal fraction of chicken cerebellum expresses a large amount of Ca(2+)-ATPase (105 kDa), which is phosphorylated by ATP in the presence of Ca2+. The Ca(2+)-ATPase activity is highly sensitive to temperature and to the presence of detergents. This ATPase has kinetic properties similar to those of chicken skeletal-muscle sarcoplasmic reticulum, as (i) it is activated by low (microM) and inhibited by high (mM) Ca2+ concentrations, (ii) it shows biphasic activation with ATP and (iii) it is inhibited by vanadate. However, the vanadate-sensitivity is at least 10 times greater than that observed in chicken skeletal or cardiac sarcoplasmic-reticulum Ca(2+)-ATPases. Thus, despite cross-reacting with antibodies against the cardiac and skeletal isoforms, the cerebellar microsomal Ca(2+)-ATPase appears to be distinct from both muscle enzymes. The Ca(2+)-ATPase is concentrated in, but not exclusive to, Purkinje neurons. In Purkinje neurons the Ca(2+)-ATPase appears to be expressed throughout the cell body, the dendritic tree (and the spines) and the axons. At the electron-microscope level the Ca(2+)-ATPase is found in smooth and rough endoplasmic-reticulum cisternae as well as in other, yet unidentified, smooth-surfaced structures.
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Affiliation(s)
- F Michelangeli
- Institute of General Pathology, University of padova, Italy
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250
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Theibert AB, Estevez VA, Ferris CD, Danoff SK, Barrow RK, Prestwich GD, Snyder SH. Inositol 1,3,4,5-tetrakisphosphate and inositol hexakisphosphate receptor proteins: isolation and characterization from rat brain. Proc Natl Acad Sci U S A 1991; 88:3165-9. [PMID: 1849645 PMCID: PMC51406 DOI: 10.1073/pnas.88.8.3165] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
High-affinity, membrane-associated inositol 1,3,4,5-tetrakisphosphate (IP4) and inositol hexakisphosphate (IP6) binding proteins were solubilized and isolated utilizing a heparin-agarose resin followed by an IP4 affinity resin. The IP6 receptor comprises a protein complex of 115-, 105-, and 50-kDa subunits, all of which comigrate under native conditions. The Kd of the receptor for IP6 is 12 nM, whereas inositol 1,3,4,5,6-pentakisphosphate (IP5), IP4, and inositol 1,4,5-trisphosphate (IP3) are 50%, 30%, and 15%, respectively, as potent. Two protein complexes copurify with the IP4 receptor fraction. A 182/123-kDa complex elutes first from the affinity column followed by a 174/84-kDa protein complex, which elutes at higher salt. Both complexes show high affinity for IP4 (Kd = 3-4 nM). IP5, IP6, and IP3 display approximately 25%, 10%, and 0.1%, respectively, the affinity of IP4. Ligand binding to IP6 and IP4 receptors is inhibited 50% by heparin at 0.1 microgram/ml. IP4 receptor proteins are stoichiometrically phosphorylated by cyclic AMP-dependent protein kinase and protein kinase C, whereas negligible phosphorylation is observed for the IP6 receptor.
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Affiliation(s)
- A B Theibert
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205
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