Bulletin of the American Physical Society
APS March Meeting 2010
Volume 55, Number 2
Monday–Friday, March 15–19, 2010; Portland, Oregon
Session C1: Poster Session I (2:00 pm - 5:00 pm)
Monday, March 15, 2010
Room: Exhibit CD
Abstract ID: BAPS.2010.MAR.C1.74
Abstract: C1.00074 : Low-Frequency Changes in Rigor Crossbridge State -- A Reflection of Correlated Motion?
Preview Abstract Abstract
(Center for Biomolecular Studies)
The structure of muscle fibers in the state of rigor takes the form of a hierarchic, interconnected filament network. In this network, individual rigor crossbridges are strongly bound to actin and exist in two different conformational states. We have used EPR spectroscopy of spin-labeled fiber bundles to monitor changes in these conformational states as a function of time. These changes appeared in the time-series data as spontaneous, irregular fluctuations taking place on many time scales -- with a period ranging from minutes to hours. When fibers were treated with the substrate analog MgPPi, the time series exhibited a slowly-decaying large-amplitude response transient. The power spectra of both types of time-series data took a 1/f-like form with a mean slope of --1.3. This kind of 1/f-like behavior has been taken to reflect complexity and long-range correlations in many types of real-world system. We conclude that the low-frequency changes we have observed in crossbridge state may reflect the presence of long-range correlated motion taking place within the rigor-state filament network.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2010.MAR.C1.74
The American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics.
1 Physics Ellipse, College Park, MD 20740-3844
Editorial Office 1 Research Road, Ridge, NY 11961-2701 (631) 591-4000
Office of Public Affairs 529 14th St NW, Suite 1050, Washington, D.C. 20045-2001 (202) 662-8700