Working model for the regulation of dynamic cell polarity in Myxococcus.

(A) Dynamic polarity switched during cellular reversals. See text for details. The orange yellow gradient symbolizes proposed MglA-GTP (orange) and MglA-GDP (yellow) distribution in the cell. At the time of reversal, an Frz-dependent unknown mechanism triggers MglA and MglB to switch to opposite poles. During the pause, the cell is depolarized, FrzS is symmetrically distributed at both cell poles, and the AglZ clusters are dispersed throughout the cytosol (green). The cycle is then reinitiated and the cell moves in the opposite direction. The sizes of the protein symbols reflect relative amounts at specific subcellular sites. (B) Cellular reversals in absence of an MglA GTP cycle. See text for details.