by Paeonia ostii, a widely cultivated woody crop known for its high α-linolenic acid content, is facing challenges due to drought stress. Drought can significantly impact plant growth and even lead to plant death, limiting the widespread cultivation of P. ostii in hilly and mountainous regions. To better understand how P. ostii responds to drought stress at the molecular level, a group of scientists led by Professor Tao Jun from Yangzhou University conducted a research study.
The team focused on the WRKY family of transcription factors, which play a vital role in a plant’s response to drought stress. However, the specific molecular mechanisms of P. ostii WRKY transcription factors in drought stress response remained unclear. In their paper published in Horticulture Research in September 2023, the research team unveiled the role of PoWRKY71 in enhancing P. ostii’s resistance to drought stress by directly regulating the light-harvesting chlorophyll a/b-binding 151 (PoCAB151) gene.
To investigate the molecular regulation mechanism of WRKY transcription factors in P. ostii’s response to drought stress, the researchers screened the WRKY family and identified PoWRKY71 as a positive regulator of drought stress. They observed that the expression of PoWRKY71 was induced by drought stress and found that it localized in the nucleus of the plant’s cells, possessing transcriptional activation activity.
Further analysis involved functional studies of the gene, where transient silencing of PoWRKY71 in P. ostii resulted in a significant reduction in drought tolerance. These silenced plants exhibited increased accumulation of reactive oxygen species (ROS), decreased chlorophyll content, and decreased photosynthesis. Conversely, overexpression of PoWRKY71 in tobacco plants enhanced their drought tolerance, leading to a decrease in ROS accumulation, an increase in chlorophyll content, and enhanced photosynthesis.
Interestingly, through the screening of genes related to chlorophyll biosynthesis and homeostasis regulation, the researchers discovered that PoCAB151, a gene encoding a light-harvesting chlorophyll a/b-binding protein, was significantly down-regulated in the silenced P. ostii plants. Subsequent experiments, such as yeast one-hybrid (Y1H), electrophoretic mobility shift assay (EMSA), and dual-luciferase assays, revealed that PoWRKY71 directly binds to the promoter of PoCAB151 and activates its expression.
Moreover, using virus-induced gene silencing (VIGS) and overexpression techniques, the scientists demonstrated that PoCAB151 plays a positive role in regulating chloroplast homeostasis and drought tolerance in P. ostii.
In conclusion, this study sheds light on a new working model involving the interaction between PoWRKY71 and PoCAB151, which plays a crucial role in P. ostii’s drought tolerance. These findings provide valuable insights for the development of drought-resistant plant varieties through breeding strategies. With further research, the molecular mechanisms underlying plant responses to drought stress can be better understood, enabling the implementation of effective strategies to mitigate the impacts of drought on crops.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
