Reconstitution of DNA segregation driven by assembly of a prokaryotic actin homolog.
نویسندگان
چکیده
Multiple unrelated polymer systems have evolved to partition DNA molecules between daughter cells at division. To better understand polymer-driven DNA segregation, we reconstituted the three-component segregation system of the R1 plasmid from purified components. We found that the ParR/parC complex can construct a simple bipolar spindle by binding the ends of ParM filaments, inhibiting dynamic instability, and acting as a ratchet permitting incorporation of new monomers and riding on the elongating filament ends. Under steady-state conditions, the dynamic instability of unattached ParM filaments provides the energy required to drive DNA segregation.
منابع مشابه
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عنوان ژورنال:
- Science
دوره 315 5816 شماره
صفحات -
تاریخ انتشار 2007