Polarity in cells and sheets. Frances Taschuk 14 April 2008. E. coli cell division. Like many other prokaryotes, E. coli cells reproduce by binary fission The plane of division is determined by the location of a ring of FtsZ protein So how does FtsZ end up in the middle of the cell?.
14 April 2008
On average, MinC concentration is highest at each end of cell
Calculate numerical solutions by turning these into difference equations, eg:
FtsZ – blue MinD – green MinE - pink
Fz = frizzled
Dsh = dishevelled
Pk = Prickle-spiny-legs
Vang = Van Gogh/strabismus
Parameters unknown, so chose ones that produced certain hair pattern phenotypes - not highly sensitive to precise values
Includes directional bias – actual mechanism unknownThe model
Able to explain autonomous mutations vs nonautonomous domineering mutations
Autonomous: cells with abnormal Dsh or some abnormal Fz functions do not affect polarity of nearby cells
Nonautonomous domineering: mutant Fz unable to recruit Vang to adjacent cellResults
fzR52 – nonautonomous – does not recruit Vang-YFP
fzF31 – autonomous – Fz still recruits Vang-YFP
Meinhardt,H., de Boer, P. A. J. 2001. Pattern formation in Escehericihia coli: a model for the pole-to-pole oscillations of Min proteins and the localization of the division site. PNAS 98:25 14202-14207.
Amonlirdviman, K, et al. 2005. Mathematical modeling of planar cell polarity to understand domineering nonautonomy. Science 307, 423-424.