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Updated: Aug 13, 2026

Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
The actin-binding cleft: functional characterisation of myosin II with a strut mutation
Setsuko Fujita-Becker1, Thomas F Reubold, Kenneth C Holmes
1Arbeitsgruppe Biophysik, Max Planck Institut für medizinische Forschung, Jahnstrasse, 29 69120, Heidelberg, Germany.
Abstract:
The myosin cross-bridge has two essential properties: to undergo the "power stroke" and to bind and release from actin - both under control of ATP binding and hydrolysis. In the absence of ATP the cross-bridge binds to actin with high affinity: the binding of ATP causes rapid release of the cross-bridge from actin. The actin binding-site is split by a deep cleft that closes on strong binding to actin. The cleft is straddled by a short polypeptide known as the "strut". In the following we summarise the structural basis of the power stroke and the control of actin affinity and then present data on the effects on actin affinity of replacing the strut by a flexible linker.
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