Direct demonstration of actin filament annealing in vitro

doi:10.1083/jcb.106.6.1947

This Article

	Full Text (PDF, 1164K)
	Alert me when this article is cited
	Citation Map

Services

	Email this article
	Similar articles in this journal
	Similar articles in PubMed
	Alert me to new content in the JCB
	Download to citation manager

Citing Articles

	Citing Articles via HighWire
	Citing Articles via CrossRef
	Citing Articles via Google Scholar

Google Scholar

	Articles by Murphy, D. B.
	Articles by Pollard, T. D.
	Search for Related Content

PubMed

	PubMed Citation
	Articles by Murphy, D. B.
	Articles by Pollard, T. D.


Social Bookmarking

	What's this?

ARTICLES

Direct demonstration of actin filament annealing in vitro

DB Murphy, RO Gray, WA Grasser and TD Pollard
Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.

Direct electron microscopic examination confirms that short actin filaments rapidly anneal end-to-end in vitro, leading over time to an increase in filament length at steady state. During annealing of mixtures of native unlabeled filaments and glutaraldehyde-fixed filaments labeled with myosin subfragment-1, the structural polarity within heteropolymers is conserved absolutely. Annealing does not appear to require either ATP hydrolysis or the presence of exogenous actin monomers, suggesting that joining occurs through the direct association of filament ends. During recovery from sonication the initial rate of annealing is consistent with a second-order reaction involving the collision of two filament ends with an apparent annealing rate constant of 10(7) M-1s-1. This rapid phase lasts less than 10 s and is followed by a slow phase lasting minutes to hours. Annealing is calculated to contribute minimally to filament elongation during the initial stages of self-assembly. However, the rapid rate of annealing of sonicated fixed filaments observed in vitro suggests that it may be an efficient mechanism for repairing breaks in filaments and that annealing together with polymer-severing mechanisms may contribute significantly to the dynamics and function of actin filaments in vivo.
Add to CiteULike CiteULike Add to Complore Complore Add to Connotea Connotea Add to Del.icio.us Del.icio.us Add to Digg Digg Facebook Add to Reddit Reddit Add to Technorati Technorati Twitter What's this?

This article has been cited by other articles:

Colakoglu, G., Brown, A. (2009). Intermediate filaments exchange subunits along their length and elongate by end-to-end annealing. JCB 185: 769-777 [Abstract] [Full Text]
Fisher, C. I., Kuo, S. C. (2009). Filament rigidity causes F-actin depletion from nonbinding surfaces. Proc. Natl. Acad. Sci. USA 106: 133-138 [Abstract] [Full Text]
Esue, O., Cordero, M., Wirtz, D., Tseng, Y. (2005). The Assembly of MreB, a Prokaryotic Homolog of Actin. J. Biol. Chem. 280: 2628-2635 [Abstract] [Full Text]
Maruo, A., Hamner, C. E., Rodrigues, A. J., Higami, T., Greenleaf, J. F., Schaff, H. V. (2004). Nitric oxide and prostacyclin in ultrasonic vasodilatation of the canine internal mammary artery. Ann. Thorac. Surg. 77: 126-132 [Abstract] [Full Text]
Guild, G. M., Connelly, P. S., Ruggiero, L., Vranich, K. A., Tilney, L. G. (2003). Long continuous actin bundles in Drosophila bristles are constructed by overlapping short filaments. JCB 162: 1069-1077 [Abstract] [Full Text]
Ryu, J., Takagi, S, Nagai, R (1995). Stationary organization of the actin cytoskeleton in Vallisneria: the role of stable microfilaments at the end walls. J. Cell Sci. 108: 1531-1539 [Abstract]