Abstract:
:We study the stochastic dynamics of growth and shrinkage of single actin filaments taking into account insertion, removal, and ATP hydrolysis of subunits either according to the vectorial mechanism or to the random mechanism. In a previous work, we developed a model for a single actin or microtubule filament where hydrolysis occurred according to the vectorial mechanism: the filament could grow only from one end, and was in contact with a reservoir of monomers. Here we extend this approach in two ways--by including the dynamics of both ends and by comparing two possible mechanisms of ATP hydrolysis. Our emphasis is mainly on two possible limiting models for the mechanism of hydrolysis within a single filament, namely the vectorial or the random model. We propose a set of experiments to test the nature of the precise mechanism of hydrolysis within actin filaments.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Ranjith P,Mallick K,Joanny JF,Lacoste Ddoi
10.1016/j.bpj.2009.12.4306subject
Has Abstractpub_date
2010-04-21 00:00:00pages
1418-27issue
8eissn
0006-3495issn
1542-0086pii
S0006-3495(10)00007-Xjournal_volume
98pub_type
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journal_title:Biophysical journal
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