Figure 7: pp2aa and pp2ac mutants are impaired in PPB formation.
From: A protein phosphatase 2A complex spatially controls plant cell division
(a–c) Immunolocalizations on root tip cells of 4-day-old seedlings using anti-tubulin (green), DAPI staining (blue) and anti-KNOLLE (red). (a) Wild-type cell at the preprophase stage (PPB marked by the arrowheads) showing KNOLLE accumulation at the trans-Golgi network. (b–d) Absence of PPBs in pp2aa1-a3 (b) and pp2ac3-c4 (c) double mutants, and in the ton1 mutant (d). Instead, dense perinuclear microtubules are visible at this stage (asterisks point out the nuclei). Scale bars, 10 μm (a–d). (e) PPB defects in pp2aa and pp2ac mutants. Mitotic stages in KNOLLE-positive cells were assessed using the anti-tubulin antibody. The number and percentage of KNOLLE-positive cells with spindles, phragmoplasts, PPBs or without PPB are indicated as well as the number of roots observed.
