Skip to main content
. 2020 Dec 21;30(24):4999–5006.e3. doi: 10.1016/j.cub.2020.09.036

Figure 4.

Figure 4

Dynamics of Polarized BASL in Regenerating Protoplasts Reflect Growth Axis

(A, C, and E) Dynamics of polarized BASL in isotropically growing regenerating protoplasts. Protoplast A, polarized BASL changes orientation from 7 o’clock (t = 0) to 4 o’clock (t = 8) and then to 1 o’clock (t = 11). The orientation of the major axis varies during regeneration until 8 h. There is no strong divergence between minor and major axis lengths (M). Protoplast C, two caps of polarized BASL (t = 0–4) become a single cap at 6 o’clock (t = 7–11). The orientation of the major axis is relatively fixed. There is no strong divergence between minor and major axis lengths (N). Protoplast E, polarized BASL appears at 5 o’clock at t = 7 and then progressively changes orientation to 1 o’clock (t = 7–19). The orientation of the major axis is relatively fixed. There is no strong divergence between minor and major axis lengths (O). (B, D, and F) Corresponding edge profiles of isotropically growing protoplasts at selected times. The black arrow heads indicate the positions marked by the arrows in the microscopy images. (G, I, and K) Dynamics of polarized BASL in anisotropically growing protoplasts. Protoplast G, BASL is diffusely polarized at t = 0 (J) and then becomes strongly polarized at t = 7 (J) just before anistropic growth becomes evident (P). The major axis also becomes fixed at t = 7. Protoplast I, polarized BASL appears at t = 4 and then disappears after 19 h. Growth is largely restricted to the major axis (Q). Protoplast K, polarized BASL appears at t = 4. Growth is largely restricted to the major axis (U). (H, J, and L) Edge profiles of anisotropically growing protoplasts at selected times. (M–U) Major and minor axis of protoplasts shown in (A), (C), (E), (G), (I), and (K). White arrows and black arrowheads indicate polarized BASL. Yellow line indicates orientation of the major axis (the length of the line is fixed and does not indicate the magnitude of the differential between major and minimum axes). N, nucleus.

Scale bars (A), (C), (E), (G), (I), (K), and (M): 20 μm. Time zero refers to when imaging was started, which was 1–2 h after cells were transferred into regeneration media. The data were obtained from four independent experiments. See also Videos S3 and S4.