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Detection and functional characterization of ryanodine receptors from sea urchin eggs.
Lokuta AJ
,
Darszon A
,
Beltrán C
,
Valdivia HH
.
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1. Immunoblot analysis, [3H]ryanodine binding, and planar lipid bilayer techniques were used to identify and characterize the functional properties of ryanodine receptors (RyRs) from Lytechinus pictus and Strongylocentrotus purpuratus sea urchin eggs. 2. An antibody against mammalian skeletal RyRs identified an approximately 400 kDa band in the cortical microsomes of sea urchin eggs while a cardiac-specific RyR antibody failed to recognize this protein. [3H]Ryanodine binding to cortical microsomes revealed the presence of a high-affinity (Kd = 13 nM), saturable (maximal density of receptor sites, Bmax = 1.56 pmol (mg protein)-1) binding site that exhibited a biphasic response to Ca2+. 3. Upon reconstitution of cortical microsomes into lipid bilayers, only sparse and unstable openings of a high-conductance cation channel were detected. Addition of crude sea urchin egg homogenate to the cytosolic (cis side) of the channel increased the frequency of openings and stabilized channel activity. The homogenate-activated channels were Ca2+ sensitive, selective for Ca2+ over Cs+, and driven by ryanodine into a long-lived subconductance state that represented approximately 40 % of the full conductance level. Homogenate dialysed in membranes with a molecular weight cut-off <= 2000 lacked the capacity to increase the frequency of RyR openings and to stabilize channel activity. 4. Direct application of cyclic adenosine diphosphoribose (cADPR) or photolysis of NPE-cADPR (''caged'' cADPR) by ultraviolet laser pulses produced transient activation of sea urchin egg RyRs. Calmodulin (CaM) failed to activate reconstituted RyRs; however, channel activity was inhibited by the CaM blocker trifluoroperazine, suggesting that CaM was necessary but not sufficient to sustain RyR activity. 5. These findings suggest that a functional Ca2+ release unit in sea urchin eggs is a complex of several molecules, one of which corresponds to a protein functionally similar to mammalian RyRs.
Brillantes,
Stabilization of calcium release channel (ryanodine receptor) function by FK506-binding protein.
1994, Pubmed
Brillantes,
Stabilization of calcium release channel (ryanodine receptor) function by FK506-binding protein.
1994,
Pubmed
Chu,
Cytoplasmic Ca2+ does not inhibit the cardiac muscle sarcoplasmic reticulum ryanodine receptor Ca2+ channel, although Ca(2+)-induced Ca2+ inactivation of Ca2+ release is observed in native vesicles.
1993,
Pubmed
Ding,
Analysis of multiple conductance states observed in Ca2+ release channel of sarcoplasmic reticulum.
1996,
Pubmed
Fruen,
Cyclic ADP-ribose does not affect cardiac or skeletal muscle ryanodine receptors.
1994,
Pubmed
Galione,
Cyclic ADP-ribose, the ADP-ribosyl cyclase pathway and calcium signalling.
1994,
Pubmed
,
Echinobase
Galione,
Ca(2+)-induced Ca2+ release in sea urchin egg homogenates: modulation by cyclic ADP-ribose.
1991,
Pubmed
,
Echinobase
Guo,
Cyclic ADP-ribose does not regulate sarcoplasmic reticulum Ca2+ release in intact cardiac myocytes.
1996,
Pubmed
,
Echinobase
Györke,
Ryanodine receptor adaptation: control mechanism of Ca(2+)-induced Ca2+ release in heart.
1993,
Pubmed
Knox,
A molecular mechanism for sensory adaptation based on ligand-induced receptor modification.
1986,
Pubmed
Lee,
Structural determination of a cyclic metabolite of NAD+ with intracellular Ca2+-mobilizing activity.
1989,
Pubmed
,
Echinobase
Lee,
Cyclic ADP ribose activation of the ryanodine receptor is mediated by calmodulin.
1994,
Pubmed
,
Echinobase
Lindsay,
How does ryanodine modify ion handling in the sheep cardiac sarcoplasmic reticulum Ca(2+)-release channel?
1994,
Pubmed
Liu,
Multiple conductance states of the purified calcium release channel complex from skeletal sarcoplasmic reticulum.
1989,
Pubmed
Lokuta,
Modulation of cardiac ryanodine receptors by sorcin.
1997,
Pubmed
Lokuta,
Modulation of cardiac ryanodine receptors of swine and rabbit by a phosphorylation-dephosphorylation mechanism.
1995,
Pubmed
McPherson,
Cortical localization of a calcium release channel in sea urchin eggs.
1992,
Pubmed
,
Echinobase
Meissner,
Ryanodine receptor/Ca2+ release channels and their regulation by endogenous effectors.
1994,
Pubmed
Meissner,
Evidence of a role for calmodulin in the regulation of calcium release from skeletal muscle sarcoplasmic reticulum.
1986,
Pubmed
Meissner,
Regulation of skeletal muscle Ca2+ release channel (ryanodine receptor) by Ca2+ and monovalent cations and anions.
1997,
Pubmed
Noguchi,
Cyclic ADP-ribose binds to FK506-binding protein 12.6 to release Ca2+ from islet microsomes.
1997,
Pubmed
Parrington,
Calcium oscillations in mammalian eggs triggered by a soluble sperm protein.
1996,
Pubmed
Rousseau,
Ryanodine modifies conductance and gating behavior of single Ca2+ release channel.
1987,
Pubmed
Sitsapesan,
Cyclic ADP-ribose competes with ATP for the adenine nucleotide binding site on the cardiac ryanodine receptor Ca(2+)-release channel.
1994,
Pubmed
Smith,
Purified ryanodine receptor from rabbit skeletal muscle is the calcium-release channel of sarcoplasmic reticulum.
1988,
Pubmed
Tanaka,
Calmodulin is a selective mediator of Ca(2+)-induced Ca2+ release via the ryanodine receptor-like Ca2+ channel triggered by cyclic ADP-ribose.
1995,
Pubmed
,
Echinobase
Tripathy,
Calmodulin activation and inhibition of skeletal muscle Ca2+ release channel (ryanodine receptor).
1995,
Pubmed
Valdivia,
Rapid adaptation of cardiac ryanodine receptors: modulation by Mg2+ and phosphorylation.
1995,
Pubmed
Wagenknecht,
Three-dimensional architecture of the calcium channel/foot structure of sarcoplasmic reticulum.
1989,
Pubmed
Walseth,
Identification of cyclic ADP-ribose-binding proteins by photoaffinity labeling.
1993,
Pubmed
,
Echinobase
Xiao,
The immunophilin FK506-binding protein modulates Ca2+ release channel closure in rat heart.
1997,
Pubmed
Xu,
Regulation of cardiac Ca2+ release channel (ryanodine receptor) by Ca2+, H+, Mg2+, and adenine nucleotides under normal and simulated ischemic conditions.
1996,
Pubmed
el-Hayek,
Peptide probe of ryanodine receptor function. Imperatoxin A, a peptide from the venom of the scorpion Pandinus imperator, selectively activates skeletal-type ryanodine receptor isoforms.
1995,
Pubmed
