图1. 类囊体超微结构的可塑性
(A) CURT1蛋白水平影响基粒结构: CURT1蛋白含量增加, 类囊体基粒片层数增加, 直径变窄; CURT1蛋白含量减少, 类囊体基粒片层数变少, 直径变宽; (B) 光强影响类囊体结构: 低光下基粒片层数增多, 高光下基粒直径变窄, 基粒高度增加; (C) PSII磷酸化水平影响类囊体膜结构: PSII磷酸化增强, 基粒直径变小、变高, 类囊体膜间隙变大, 囊腔增厚; PSII磷酸化水平下降, 基粒直径变大, 类囊体膜间隙变小, 基粒层数变少。LL: 低光; HL: 高光; PSII: 光系统II; LHCII: 捕光蛋白复合物II; CURT1: 弯曲类囊体膜蛋白1

Figure 1. The plasticity of thylakoid ultrastructure
(A) Effects of CURT1 levels on granum dimensions: With the level of CURT1 proteins increased, the grana displays more layers of membrane and decreased diameter; Grana without CURT1 proteins significantly increased in diameter but contain far fewer layers of membrane; (B) Effects of changes in light conditions on granum dimensions: under low light levels, the numbers of layers in grana stacks are increased, and high light intensities lead to significant reduction in the diameter, and to partial transversal unstacking of grana discs; (C) Effects of PSII phosphorylation on granum dimensions: increased levels of PSII phosphorylation lead to significant reduction in the diameter, the enlargement of the vertical gaps between thylakoid layers, and swelling of the thylakoid lumen; Decreased levels of PSII phosphorylation lead to increased diameter, decreased gaps of adjacent layers within the granum, and fewer layers of membrane. LL: Low light; HL: High light; PSII: Photosystem II; LHC II: Light-harvesting complex II; CURT1: CURVATURE THYLAKOID 1