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Publications [#113174] of Harold P. Erickson

Papers Published

  1. K Anderson, FA Lai, QY Liu, E Rousseau, HP Erickson, G Meissner, Structural and functional characterization of the purified cardiac ryanodine receptor-Ca2+ release channel complex., The Journal of biological chemistry, UNITED STATES, vol. 264 no. 2 (January, 1989), pp. 1329-35, ISSN 0021-9258
    (last updated on 2009/02/12)

    Abstract:
    Using density gradient centrifugation and [3H]ryanodine as a specific marker, the ryanodine receptor-Ca2+ release channel complex from Chaps-solubilized canine cardiac sarcoplasmic reticulum (SR) has been purified in the form of an approximately 30 S complex, comprised of Mr approximately 400,000 polypeptides. Purification resulted in a specific activity of approximately 450 pmol bound ryanodine/mg of protein, a 60-70% recovery of ryanodine binding activity, and retention of the high affinity ryanodine binding site (KD = 3 nM). Negative stain electron microscopy revealed a 4-fold symmetric, four-leaf clover structure, which could fill a box approximately 30 x 30 nm and was thus morphologically similar to the SR-transverse-tubule, junctionally associated foot structure. The structural, sedimentation, and ryanodine binding data strongly suggest there is one high affinity ryanodine binding site/30 S complex, comprised of four Mr approximately 400,000 subunits. Upon reconstitution into planar lipid bilayers, the purified complex exhibited a Ca2+ conductance (70 pS in 50 mM Ca2+) similar to that of the native cardiac Ca2+ release channel (75 pS). The reconstituted complex was also found to conduct Na+ (550 pS in 500 mM Na+) and often to display complex Na+ subconducting states. The purified channel could be activated by micromolar Ca2+ or millimolar ATP, inhibited by millimolar Mg2+ or micromolar ruthenium red, and modified to a long-lived open subconducting state by ryanodine. The sedimentation, subunit composition, morphological, and ryanodine binding characteristics of the purified cardiac ryanodine receptor-Ca2+ release channel complex were similar to those previously described for the purified ryanodine receptor-Ca2+ release channel complex from fast-twitch skeletal muscle.

    Keywords:
    Animals • Calcium • Dogs • Heart Ventricles • Ion Channels • Kinetics • Lipid Bilayers • Molecular Weight • Muscles • Myocardium • Organ Specificity • Receptors, Cholinergic • Ryanodine • Ryanodine Receptor Calcium Release Channel • Sarcoplasmic Reticulum • isolation & purification • metabolism • metabolism*


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