Extended Data Fig. 1: Secondary cell wall patterns of midd mutants.
(a) Density of secondary cell wall pits in roots (n = 30 cells, one cell/plant). (b) Density of secondary cell wall pits when pairs of distinct small pits (DPs) were counted as one pit (n = 30 cells, one cell/plant). (c) Areas of secondary cell wall pits without DPs in WT, midd1, midd2, midd1 midd2, midd1 midd2/pMIDD1:GFP–MIDD1, kinesin-13a, and kinesin-13a/pKinesin-13A:Kinesin-13A-tagRFP plants (n = 100 pits from 15 plants for WT, 13 plants for midd1, 22 plants for midd2, 14 plants for midd1 midd2, 15 plants for midd1 midd2/pMIDD1:GFP-MIDD1, 12 plants for kinesin-13a, 15 plants for kinesin-13a/pKinesin-13A:Kinesin-13A-tagRFP). (DP) indicates the area of DPs. (d) Electron micrographs of protoxylem vessels in roots. Red arrowheads indicate the ingrowth of secondary cell walls. Scale bar = 2 μm. Data are representative of three independent experiments. (e) Three replicated measurements of stripe densities (sample number of upper left, upper right and lower left panels: n = 20, 20, and 20 cells for WT; 21, 20, and 15 cells for midd1 midd2; 16, 20, and 18 cells for midd1 midd2/pMIDD1:GFP-MIDD1; 19, 21, and 21 cells for kinesin-13a; 21, 20, and 19 cells for kinesin-13a/pKinesin-13A:Kinesin-13A-tagRFP; 20, 19, and 21 cells for midd1 midd2 kinesin-13a; 20, 20, and 20 cells for rop7 rop8 rop11; 19, 20, and 20 cells for rop7 rop8 rop11/pROP7:ROP7; 20, 20, and 19 cells for rop7 rop8 rop11/pROP8:ROP8; and 20, 20, 20 cells for rop7 rop8 rop11/pROP11:ROP11; one cell/plant). Letters indicate statistically significant differences (p < 0.05) determined using one-way ANOVA, followed by Tukey’s test. Box plot indicates the median (horizontal line) and the interquartile range from 25 to 75%, and whiskers indicate SD (A-C, and E). (f) T-DNA insertions of midd1 and midd2 mutants.
