Figures & data
Figure 1 Model of the actin-auxin oscillator. In the absence of auxin, actin is organized in bundles that do not support the localization of auxin-efflux carriers in the plasma membrane, such that these carriers are clustered inside the cell. Upon addition of IAA or NAA (but not 2,4-D that is perceived by a different receptor), these bundles detach into fine actin strands that efficiently support the polar localization of the auxin-efflux carriers. The altered auxin efflux will transiently reduce the intracellular concentration of auxin (which will be later compensated by auxin drainage from neighboring cells) such that actin returns to a more bundled configuration. This will again affect the localization and thus the activity of efflux-carriers such that intracellular auxin concentration increases again. Since the cycling of transporters is a rapid process, the frequency of the oscillator is mainly determined by the velocity of actin reorganization (in the range of around 20 min).
