Bacterial actin homolog ParM: arguments for an apolar, antiparallel double helix.
نویسنده
چکیده
The bacterial actin homolog ParM has always been modeled as a polar filament, comprising two parallel helical strands, like actin itself. I present arguments here that ParM may be an apolar filament, in which the two helical strands are antiparallel.
منابع مشابه
An actin homolog of the archaeon Thermoplasma acidophilum that retains the ancient characteristics of eukaryotic actin.
Actin, a central component of the eukaryotic cytoskeleton, plays a crucial role in determining cell shape in addition to several other functions. Recently, the structure of the archaeal actin homolog Ta0583, isolated from the archaeon Thermoplasma acidophilum, which lacks a cell wall, was reported by Roeben et al. (J. Mol. Biol. 358:145-156, 2006). Here we show that Ta0583 assembles into bundle...
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End-on view of the atomic model of the bacterial actinlike ParM protein double-helical fi lament, generated from an electron microscopic reconstruction. A bipolar spindle of antiparallel ParM fi laments pushes plasmids to the cell poles, constituting the simplest known apparatus for the segregation of genetic information. The loops on the outside of the 8to 9-nanometer-thick fi laments are invo...
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ParM is a prokaryotic actin homologue, which ensures even plasmid segregation before bacterial cell division. In vivo, ParM forms a labile filament bundle that is reminiscent of the more complex spindle formed by microtubules partitioning chromosomes in eukaryotic cells. However, little is known about the underlying structural mechanism of DNA segregation by ParM filaments and the accompanying ...
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ورودعنوان ژورنال:
- Journal of molecular biology
دوره 422 4 شماره
صفحات -
تاریخ انتشار 2012