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Contact
Info:
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Courier
Address:
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Phone:
(203) 785-4066
Fax:
(203) 785-4951
e-mail:
Know.Chandler@yale.edu |
333
Cedar Street,
SHM
B163c
New
Haven, CT 06510 |
Excitation-contraction
coupling in skeletal muscle.
Calcium ions
play an important role in intracellular communication in many cells. In
vertebrate twitch muscle fibers, for example, contraction is normally
activated by a depolarization of the membranes of the transverse tubular
system. This leads to a movement of calcium ions from inside the sarcoplasmic
reticulum (SR), where they are stored, into the myoplasm, where they can
bind to the calcium regulatory sites on troponin so that contraction can
occur. My research objectives are to understand the factors that control
the flow of calcium ions through the calcium channels in the SR membrane
(ryanodine receptor protein). These factors include the voltage across
the tubular membranes, which is sensed by their voltage sensors (the dihydropyrydine
receptors), and free [Ca2+] itself, which can cause calcium-induced calcium
release or calcium inactivation of calcium release. Electrophysiological
methods are used to monitor currents generated by the voltage sensors,
and optical methods are used to monitor the myoplasmic free calcium concentration,
which can be used to estimate SR calcium release.
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Figure caption:
Relative timing of the action potential (AP), myoplasmic free
[Ca] and the rate of Ca release from the sarcoplasmic reticulum
(d[Ca]T/dt) and the binding of Ca to the Ca- regulatory sites
on troponin ([CaTrop]).
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Selected
publications:
Click
 for PDF
Hollingworth
S., J. Peet, W.K. Chandler, and S.M. Baylor (2001).
Calcium sparks in intact skeletal muscle fibers of the frog. Journal
of General Physiology. 118: 653-678. 
Baylor, S.M., S. Hollingworth, and W.K. Chandler (2002).
Comparison of simulated and measured sparks in intact skeletal muscle
fibers of the frog. Journal of General Physiology. 120: 349-368.
Hollingworth, S., W.K. Chandler, and S.M. Baylor (2006).
Effects of tetracaine on voltage-activated calcium sparks in frog intact
skeletal muscle fibers. Journal of General Physiology. 127: 291-307.
knox.chandler@yale.edu
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