Figure 9.

Chloroplast morphogenesis is a highly regulated process. A, ET slice image of a normal-sized wild-type (WT) chloroplast with typical thylakoid differentiation into stacked (grana) and unstacked domains. B, 3D model based on the chloroplast in (A). Green represents thylakoid membranes, blue represents starch grains. C, ET slice image of an oversized chloroplast (compare scale bars) with aberrant thylakoid membrane organization in an Arabidopsis flz mutant (Liang et al., 2018b). FLZ is a dynamin-like protein, and thylakoid fusion is inhibited in the mutant (Gao et al., 2006; Findinier et al., 2019). Instead of a stroma-wide network, thylakoids form discrete spirals in the mutant. D, 3D model based on the chloroplast in (C). Scale bars = 500 nm.