Literature

A discussion of ID-related Reading

Post details: Insights into the workings of the fastest muscles

11/22/06

by David Tyler 11:07:10 am, Categories: Literature - Articles, 360 words

Insights into the workings of the fastest muscles

The thoracic musculature of insects that enables very high wing beat frequencies is described as “striking”. At a molecular level, a series of interrelated characteristics are required, including: “the highest measured detachment rate of myosin from actin”, “an exceptionally weak affinity of MgATP for myosin” and “a unique rate-limiting step in the cross-bridge cycle at the point of inorganic phosphate release.” Although this paper is written from an evolutionary perspective, the authors are continually flagging up design issues at the molecular level. The properties of the materials used to power flight are remarkable.

An exceptionally fast actomyosin reaction powers insect flight muscle
Douglas M. Swank, Vivek K. Vishnudas and David W. Maughan
Proc. Natl. Acad. Sci. USA. November 14, 2006, vol. 103, no. 46, 17543-17547 | doi:10.1073/pnas.0604972103.

Insects, as a group, have been remarkably successful in adapting to a great range of physical and biological environments, in large part because of their ability to fly. The evolution of flight in small insects was accompanied by striking adaptations of the thoracic musculature that enabled very high wing beat frequencies. At the cellular and protein filament level, a stretch activation mechanism evolved that allowed high-oscillatory work to be achieved at very high frequencies as contraction and nerve stimulus became asynchronous. At the molecular level, critical adaptations occurred within the motor protein myosin II, because its elementary interactions with actin set the speed of sarcomere contraction. Here, we show that the key myosin enzymatic adaptations required for powering the very fast flight muscles in the fruit fly Drosophila melanogaster include the highest measured detachment rate of myosin from actin (forward rate constant, 3,698 s-1), an exceptionally weak affinity of MgATP for myosin (association constant, 0.2 mM-1), and a unique rate-limiting step in the cross-bridge cycle at the point of inorganic phosphate release. The latter adaptations are constraints imposed by the overriding requirement for exceptionally fast release of the hydrolytic product MgADP. Otherwise, as in Drosophila embryonic muscle and other slow muscle types, a step associated with MgADP release limits muscle contraction speed by delaying the detachment of myosin from actin.

For further reading: Myosin's need for speed, JCB, 2006. 175(4), 519. | doi:10.1083/jcb.1754rr3
http://www.jcb.org/cgi/content/full/175/4/519b

Literature

Recently (cached)
Recently (no cache)

October 2008
Mon	Tue	Wed	Thu	Fri	Sat	Sun
<< <		> >>
		1	2	3	4	5
6	7	8	9	10	11	12
13	14	15	16	17	18	19
20	21	22	23	24	25	26
27	28	29	30	31

Last comments

Search

Linkblog

Links - Groups and Organizations

Access Research Network
Discovery Institute
Evolution News Blog
Evolution has become a favorite topic of the news media recently, but for some reason, they never seem to get the story straight. The staff at Discovery Institute's Center for Science and Culture started this Blog to set the record straight and make sure you knew "the rest of the story".
Intelligent Design Network (IDNet)
Intelligent Design Undergraduate Research Center
Intelligent Reasoning
A blogger from New England offers his intelligent reasoning.
International Society for Complexity, Information, and Design (ISCID)
Telic Thoughts
We are a group of individuals, coming from diverse backgrounds and not speaking for any organization, who have found common ground around teleological concepts, including intelligent design. We think these concepts have real potential to generate insights about our reality that are being drowned out by political advocacy from both sides. We hope this blog will provide a small voice that helps rectify this situation.
The Design Inference - The Writings of William A. Dembski
The Intelligent Design and Evolution Awareness Center (IDEA)
www.themonkeytrial.com
Website dedicated to comparing scenes from the "Inherit the Wind" movie with factual information from actual Scopes Trial. View 37 clips from the movie and decide for yourself if this movie is more fact or fiction.

Links - Of General Interest

A Brief View of Time and Those That Live There
Don Cicchetti blogs on: Culture, Music, Faith, Intelligent Design, Guitar, Audio
A Quick Guide to Sequenced Genomes
ARN Related Web Links
Creation/Evolution Quotes
Australian biologist Stephen E. Jones maintains one of the best origins "quote" databases around. He is meticulous about accuracy and working from original sources.
CreationEvolutionDesign
Most guys going through midlife crisis buy a convertible. Austrialian Stephen E. Jones went back to college to get a biology degree and is now a proponent of ID and common ancestry.
Darwinian Fairytales by David Stove
Complete zipped downloadable pdf copy of David Stove's devastating, and yet hard-to-find, critique of neo-Darwinism entitled "Darwinian Fairytales"
ID The Future
Intelligent Design The Future is a multiple contributor weblog whose participants include the nation's leading design scientists and theorists: biochemist Michael Behe, mathematician William Dembski, astronomer Guillermo Gonzalez, philosophers of science Stephen Meyer, and Jay Richards, philosopher of biology Paul Nelson, molecular biologist Jonathan Wells, and science writer Jonathan Witt. Posts will focus primarily on the intellectual issues at stake in the debate over intelligent design, rather than its implications for education or public policy.
John Mark Reynolds Blog
A Philosopher's Journey: Political and cultural reflections of John Mark N. Reynolds. Dr. Reynolds is Director of the Torrey Honors Institute at
Biola University.
NASA Astronomy Picture of the Day