Fig. 2

Mechanical responses of PIN1 and MT after LaCl₃ treatments. a, b PIN1-GFP shows polarized subcellular localization 3 h after local cell ablation with a glass pipette, without pharmacological treatment. c, d PIN1-GFP reorientation was not detected 3 h after cell ablation following 15 min pretreatment with 5 mM LaCl₃ without a subsequent water rinse. e At three additional hours after LaCl₃ washout, PIN1-GFP has reoriented away from the ablation site. a–e LUT is gem in Fiji-ImageJ software. f–m Confocal projections of laser-ablated SAMs expressing pPIN1::PIN1-GFP (magenta in f, h, j, l or red in g, i, k, m) and pML1::mcherry-MAP4 (green). f, g Mock treated meristem just after ablation. h, i The same meristem as in f and g, 4 h later. j–m Another laser ablated meristem, treated with 5 mM LaCl₃ 15 min before ablation and imaged at 0 h after ablation (j, k) and 4 h later without a water rinse during incubation (l, m). Note difference in PIN1 polarity response comparing h with l although MTs re-oriented circumferentially in both cases (compare i with m). a–m Similarly colored dots mark the same cells tracked over time. Scale bars: 20 µm (a–e) and 10 µm (f–m)