Troponin I converts the skeletal muscle ryanodine receptor into a rectifying calcium release channel
Open Access
- 5 March 2002
- journal article
- Published by Wiley in FEBS Letters
- Vol. 515 (1-3) , 155-158
- https://doi.org/10.1016/s0014-5793(02)02463-8
Abstract
The goal of our present studies has been to find novel ryanodine receptor (RyR1) interacting polypeptides that modulate the channel activity from the luminal side of RyR1. Using K+ as charge carrier for recording of single channel events here we demonstrate a very unexpected observation that troponin I substantially alters RyR's gating behavior, and that RyR1 in association with troponin I becomes a rectifying Ca2+ release channel. Troponin I rapidly locks the RyR1 in a non‐conducting state only at a negative holding potential, and only when applied to the luminal side; switching to a positive holding potential results in the channel returning to its original activity, immediately. A hypothesis is proposed to account for how an intraluminally located, positively charged molecule might function as a RyR1 regulator under physiological conditions.Keywords
This publication has 23 references indexed in Scilit:
- Signaling—2000 and BeyondCell, 2000
- The identification of the phosphorylated 150/160-kDa proteins of sarcoplasmic reticulum, their kinase and their association with the ryanodine receptorBiochimica et Biophysica Acta (BBA) - Biomembranes, 1996
- Sarcoplasmic reticulum lumenal Ca2+ has access to cytosolic activation and inactivation sites of skeletal muscle Ca2+ release channelBiophysical Journal, 1996
- VDAC/porin is present in sarcoplasmic reticulum from skeletal muscleFEBS Letters, 1996
- The role of Ca2+ ions in excitation-contraction coupling of skeletal muscle fibresBiochimica et Biophysica Acta (BBA) - Reviews on Biomembranes, 1995
- Ryanodine Receptor/Ca2+ Release Channels and Their Regulation by Endogenous EffectorsAnnual Review of Physiology, 1994
- Enhancement of Ca2+ release channel activity by phosphorylation of the skeletal muscle ryanodine receptorFEBS Letters, 1993
- A novel genetic system to detect protein–protein interactionsNature, 1989
- Primary structure and expression from complementary DNA of skeletal muscle ryanodine receptorNature, 1989
- Biochemistry and Biophysics of Excitation-Contraction CouplingAnnual Review of Biophysics, 1989