Simulated dynamics of SoPIN1, PIN1b, and PIN1a during the initiation of a single convergence point and vein segment.

<p>Columns (1–5) correspond to progress of time (5960, 6100, 6430, 6610, 6850 simulation time units). Row (A) SoPIN1, (B) PIN1b, (C) PIN1a, and (D) combined. The concentration of each PIN in the cell membrane is indicated by the width of the colored wedges along each cell (increasing with concentration). The concentrations of each PIN on the membrane, and auxin in each cell, are also indicated by colors, as shown by the scale bars on the right. In rows (B) and (D), the direction and magnitude of PIN1b polarization is further highlighted by a blue arrow in each cell. Cells in the region outlined in white in Panel 2B exhibit increased polarization following the formation of a new convergence point (compare to Panel 1B). The region outlined in white in Panel 3B is the triangular fan of cells with increased polarization at the rootward end of the developing vein. The white arrow in Panel 3C points to a gap in auxin concentration along an emerging vein. The white arrow in Panel 4C points to two cells exhibiting a transient increase in auxin concentration.