Structural dynamics of troponin during activation of skeletal muscle.
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ABSTRACT:
SUBMITTER: Fusi L
PROVIDER: S-EPMC3970506 | biostudies-literature | 2014 Mar
REPOSITORIES: biostudies-literature
Publications
Structural dynamics of troponin during activation of skeletal muscle.
Fusi Luca L Brunello Elisabetta E Sevrieva Ivanka R IR Sun Yin-Biao YB Irving Malcolm M
Proceedings of the National Academy of Sciences of the United States of America 20140310 12
Time-resolved changes in the conformation of troponin in the thin filaments of skeletal muscle were followed during activation in situ by photolysis of caged calcium using bifunctional fluorescent probes in the regulatory and the coiled-coil (IT arm) domains of troponin. Three sequential steps in the activation mechanism were identified. The fastest step (1,100 s(-1)) matches the rate of Ca(2+) binding to the regulatory domain but also dominates the motion of the IT arm. The second step (120 s(- ...[more]
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