Junctional membrane Ca²⁺ dynamics in human muscle fibers are altered by malignant hyperthermia causative RyR mutation.

ABSTRACT: We used the nanometer-wide tubules of the transverse tubular (t)-system of human skeletal muscle fibers as sensitive sensors for the quantitative monitoring of the Ca²⁺-handling properties in the narrow junctional cytoplasmic space sandwiched between the tubular membrane and the sarcoplasmic reticulum cisternae in single muscle fibers. The t-system sealed with a Ca²⁺-sensitive dye trapped in it is sensitive to changes in ryanodine receptor (RyR) Ca²⁺ leak, the store operated calcium entry flux, plasma membrane Ca pump, and sodium-calcium exchanger activities, thus making the sealed t-system a nanodomain Ca²⁺ sensor of Ca²⁺ dynamics in the junctional space. The sensor was used to assess the basal Ca²⁺-handling properties of h

SUBMITTER: Cully TR 

PROVIDER: S-EPMC6094124 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature