Peng Yuting, Jiang Yuyan, Chen Qing, Lin Yuanxiu, Li Mengyao, Zhang Yunting, Wang Yan, He Wen, Zhang Yong, Wang Xiaorong, Tang Haoru, Luo Ya
College of Horticulture, Sichuan Agricultural University, Chengdu, Sichuan Province, China.
College of Horticulture, Sichuan Agricultural University, Chengdu, Sichuan Province, China.
Plant Physiol Biochem. 2025 Jan;218:109327. doi: 10.1016/j.plaphy.2024.109327. Epub 2024 Nov 23.
Photosynthesis is a source of energy for various types of plant life activities and is essential for plant growth and development. Consequently, the study of photosynthetic mechanisms has been a hot spot. Leaf color mutants has always been ideal materials for exploring the mechanisms of chlorophyll metabolism and photosynthesis. In this study, we identified a leaf color mutant of 'Benihoppe' strawberry in the field, which exhibited a darker green leaf color compared with the wild type. The content of total chlorophyll and carotenoid in the mutant leaves was elevated by 7.44-20.23% and 8.9-21.92%, respectively, compared with that of the wild type. Additionally, net photosynthetic rate in the mutant increased by 20.13%. Further transcriptome analysis showed that significant upregulation of genes such as GLK1, PPR, and MORF9 in the mutant leaves, which promoted chloroplast development. The expression levels of UROD, PPOC, PORA, CHLG, and CPOX were significantly upregulated during chlorophyll synthesis, while the expression levels of HCAR and CYP89A9 were significantly downregulated during chlorophyll degradation, thus leading to the accumulation of chlorophyll in mutant leaves. The upregulation of gene expression levels such as PetM, AtpD, PGK, and RPI4 during photosynthesis promoted multiple stages of light and dark reaction, thereby enhancing the photosynthetic capacity of the mutant. And the changes in metabolites such as monogalactosyl monoacylglycerol (MGMG), glucuronosyldiacylglycerol (GlcADG), raffinose, etc. also indicate that the mutant has metabolic differences in chloroplast composition and photosynthesis compared to 'Benihoppe'. The above results not only deepen our understanding of the mechanism behind the dark-green leaf color in strawberry mutants but also provide potential genetic resources for cultivating strawberry varieties with enhanced photosynthetic capacity.
光合作用是各类植物生命活动的能量来源，对植物的生长发育至关重要。因此，光合机制的研究一直是热点。叶色突变体一直是探索叶绿素代谢和光合作用机制的理想材料。在本研究中，我们在田间鉴定出一个‘红颜’草莓叶色突变体，与野生型相比，其叶片颜色呈深绿色。与野生型相比，突变体叶片中总叶绿素和类胡萝卜素含量分别提高了7.44 - 20.23%和8.9 - 21.92%。此外，突变体的净光合速率提高了20.13%。进一步的转录组分析表明，突变体叶片中GLK1、PPR和MORF9等基因显著上调，促进了叶绿体发育。在叶绿素合成过程中，UROD、PPOC、PORA、CHLG和CPOX的表达水平显著上调，而在叶绿素降解过程中，HCAR和CYP89A9的表达水平显著下调，从而导致突变体叶片中叶绿素积累。光合作用过程中PetM、AtpD、PGK和RPI4等基因表达水平的上调促进了光反应和暗反应的多个阶段，从而增强了突变体的光合能力。单半乳糖基单酰甘油（MGMG）、葡萄糖醛酸二酰甘油（GlcADG）、棉子糖等代谢物的变化也表明，与‘红颜’相比，该突变体在叶绿体组成和光合作用方面存在代谢差异。上述结果不仅加深了我们对草莓突变体深绿叶色背后机制的理解，也为培育光合能力增强的草莓品种提供了潜在的遗传资源。
