編者按：最新的Cell上發(fā)文稱發(fā)現(xiàn)了細菌維持其形態(tài)的骨架蛋白，非常有意思,。
Cell, Vol 115, 705-713, 12 December 2003

The Bacterial Cytoskeleton: An Intermediate Filament-Like Function in Cell Shape
Nora Ausmees , Jeffrey R. Kuhn , and Christine Jacobs-Wagner
Various cell shapes are encountered in the prokaryotic world, but how they are achieved is poorly understood. Intermediate filaments (IFs) of the eukaryotic cytoskeleton play an important role in cell shape in higher organisms. No such filaments have been found in prokaryotes. Here, we describe a bacterial equivalent to IF proteins, named crescentin, whose cytoskeletal function is required for the vibrioid and helical shapes of Caulobacter crescentus. Without crescentin, the cells adopt a straight-rod morphology. Crescentin has characteristic features of IF proteins including the ability to assemble into filaments in vitro without energy or cofactor requirements. In vivo, crescentin forms a helical structure that colocalizes with the inner cell curvatures beneath the cytoplasmic membrane. We propose that IF-like filaments of crescentin assemble into a helical structure, which by applying its geometry to the cell, generates a vibrioid or helical cell shape depending on the length of the cell.