SlGRAS17 negatively regulates chlorophyll biosynthesis in tomato
Jianyong Wang1, Qingfang Lin1, Huizhu Yang1
1School of Life Sciences, Jiangsu Normal University, Xuzhou, Jiangsu 221116, China.
Plant Physiology
|March 4, 2026
Summary
We identified SlGRAS17 as a negative regulator of chlorophyll in tomato. This transcription factor represses chlorophyll biosynthesis by interacting with SlSEU3 and SlLUG to control SlGLK1 expression.
Area of Science:
- Plant Molecular Biology
- Plant Physiology
- Agricultural Science
Background:
- Chlorophyll content is crucial for photosynthesis and visual quality in tomato (Solanum lycopersicum).
- Positive regulators of chlorophyll biosynthesis are well-studied, but repression mechanisms are less understood.
- Understanding chlorophyll repression is key to improving tomato crop yield and quality.
Purpose of the Study:
- To identify novel negative regulators of chlorophyll biosynthesis in tomato.
- To elucidate the molecular mechanism by which SlGRAS17 controls chlorophyll accumulation.
- To characterize the interaction of SlGRAS17 with other regulatory factors.
Main Methods:
- Isolation and characterization of a high-chlorophyll mutant (hcm1).
- CRISPR/Cas9 gene editing to generate slgras17 mutants.
- Analysis of SlGRAS17 localization, DNA binding, and protein interactions (co-immunoprecipitation).
- Virus-induced gene silencing (VIGS) for genetic analysis.
Main Results:
- The GRAS transcription factor SlGRAS17 acts as a negative regulator of chlorophyll accumulation.
- slgras17 mutants exhibit dark-green leaves with increased chlorophyll content.
- SlGRAS17 directly represses SlGLK1 transcription by binding to its promoter.
- SlGRAS17 functions with co-repressors SlSEU3 and SlLUG to form a repressive complex.
Conclusions:
- SlGRAS17 is a key component of a novel transcriptional module that represses chlorophyll biosynthesis in tomato.
- The SlGRAS17-SlSEU3-SlLUG complex fine-tunes chlorophyll levels by regulating SlGLK1.
- This discovery provides new targets for genetic improvement of tomato quality and photosynthetic efficiency.
Related Concept Videos
01:25Cell Signaling in Plants
6.9K
Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...
6.9K
02:00Photoreceptors and Plant Responses to Light
28.7K
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.
28.7K