Abstract:
:We propose a motility mechanism that may result in the displacement of objects within the cell. The mechanism, which we call polymer-guided diffusion, involves a microscopic cycle of polymer association and dissociation from a lateral binding site. Reassociation occurs at the polymer subunit adjacent to that which has just dissociated, thus generating an apparent sliding movement. The displacement involves only free diffusion and the spontaneous fluctuations of the polymer; the movement thus requires no other energy sources than thermal energy and the energy originally required for the formation of the polymer. In this manner polymer-associated organelles can be guided (inevitably) by diffusional processes toward a final destination. The specific example of the anaphase movement of chromosomes poleward is detailed.
journal_name
Proc Natl Acad Sci U S Aauthors
Garel JR,Job D,Margolis RLdoi
10.1073/pnas.84.11.3599subject
Has Abstractpub_date
1987-06-01 00:00:00pages
3599-603issue
11eissn
0027-8424issn
1091-6490journal_volume
84pub_type
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