Figure 9.

Model of formin localization and functions during cytokinesis. During cytokinesis group I formins localize on the cell plate membrane and in the cell plate assembly matrix; group II formins localize on microtubules. The first function of formins is nucleating F-actin by the cell plate (A). The second function is promoting microtubule elongation by stabilizing tubulin protofilament flares on the growing plus-tips (B). When microtubule tip approaches the cell plate, formins dock the microtubule tip to the cell plate assembly matrix (CPAM) through interaction with EB1 proteins (C). Formins localized within CPAM and on the cell plate stabilizes microtubule plus-ends (D). Formins can also contribute to the cell plate membrane recycling by facilitating recruitment of DRPs to the cell plate through yet unknown mechanism (E). Only one-half of the phragmoplast is shown in the model.