Ryanodine receptor binding to FKBP12 is modulated by channel activation state

Jones, Jonathan-Lee, Reynolds, Deborah Fidelis, Lai, Francis Anthony ORCID: https://orcid.org/0000-0003-2852-8547 and Blayney, Lynda Mary 2005. Ryanodine receptor binding to FKBP12 is modulated by channel activation state. Journal of Cell Science (JCS) 118 (20) , pp. 4613-4619. 10.1242/jcs.02582

Full text not available from this repository.

Abstract

Ryanodine receptor (RyR) Ca2+ release channels undergo a conformational change between the open and closed states. Its protein modulator, FK506 binding protein 12 (FKBP12), stabilises the channel gating between the four subunits that surround a central Ca2+-conducting pore. To understand the interdependence of RyR and FKBP12 binding, physiological and pharmacological agents were used to modulate the RyR open/closed state. ELISA sandwich binding assays showed that FKBP12 binding was dependent on the free Ca2+ and was lower at 1-10 µM free Ca2+ compared with 1 mM EGTA and 1 mM Ca2+, and this effect was enhanced by the inclusion of 1 mM ATP. Ruthenium red increased the binding of FKBP12. [3H]Ryanodine binding confirmed that 1 mM EGTA, 1 mM Ca2+ and 1 µM ruthenium red closed the channel, whereas 1 µM free Ca2+, 1 µM free Ca2+ + 1 mM ATP, or 10 mM caffeine opened it. These binding conditions were used in surface plasmon resonance studies to measure equilibrium binding kinetics. The affinity constant KA was significantly greater for the closed than the open channel, a change mediated by a decreased dissociation rate constant, kd. The results show that surface plasmon resonance is a powerful technique that can measure differences in RyR1 equilibrium binding kinetics with FKBP12.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Schools > Medicine
Uncontrolled Keywords:	Ryanodine receptor ; FKBP12 ; Surface plasmon resonance ; Channel activation state
Publisher:	Company of Biologists
ISSN:	1477-9137
Last Modified:	17 Oct 2022 08:23
URI:	https://orca.cardiff.ac.uk/id/eprint/38

Citation Data

Cited 19 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item