Unlocking the secret to salt-resistant roots in bok choy
Nanjing Agricultural University The Academy of Science
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A proposed working model for BcWRKY33A-mediated root development in Bok choy. The transcription levels of BcWRKY25 and BcWRKY33A increased when exposed to NaCl stress. BcWRKY25 binds to the promoter of BcWRKY33A, enhancing its expression. As a result, the elevated BcWRKY33A directly activates the expression of BcLRP1 and BcCOW1, leading to the promotion of primary root elongation and root hair development.
view moreCredit: Horticulture Research
A new study explores the genetic mechanisms behind root development and salt tolerance in Bok choy, a widely grown vegetable known for its shallow roots. Researchers identified a key regulatory module involving BcWRKY33A, BcLRP1, and BcCOW1 that promotes root elongation and stabilizes root hair development under salt stress. The findings reveal how plants adapt to salinity by enhancing root system performance, which could inform strategies for developing more resilient crops in challenging environmental conditions.
Salt stress severely impacts plant growth, particularly in crops like Bok choy, which has a shallow root system. While genetic factors play a critical role in root architecture and stress responses, the molecular mechanisms underlying these processes remain poorly understood. WRKY transcription factors, such as BcWRKY33A, have been implicated in regulating root development and stress tolerance, but their exact roles in salt stress adaptation were unclear. Based on these challenges, further research is needed to fully elucidate the pathways involved in salt tolerance.
This study (DOI: 10.1093/hr/uhae280), published in Horticulture Research on September 28, 2024, unveils the role of BcWRKY33A in regulating root development under salt stress. Conducted by researchers from Nanjing Agricultural University and other institutions, this research focuses on how BcWRKY33A, in conjunction with other key genes, promotes root growth in response to salt stress, offering new insights for improving crop resilience.
The researchers discovered that BcWRKY33A, a transcription factor induced by salt stress, directly regulates the expression of BcLRP1 and BcCOW1, two genes critical for root development. BcLRP1 enhances primary root elongation, while BcCOW1 stabilizes root hair morphology. The study further identifies BcWRKY25 as an upstream regulator that triggers BcWRKY33A expression in response to salt stress. By manipulating these genetic pathways, the team successfully enhanced root growth and salt tolerance in transgenic plants. These results offer valuable strategies for breeding salt-tolerant crops, particularly in areas affected by salinity.
Dr. Xilin Hou, a leading researcher in the field, notes, "Our findings highlight the intricate genetic network that controls root development under stress. By understanding how BcWRKY33A regulates root architecture, we can develop more resilient crops, which is crucial in the face of increasing soil salinity challenges."
This research provides a comprehensive genetic framework for improving salt tolerance in crops like Bok choy. The insights into BcWRKY33A and its regulatory partners could aid in the development of genetically engineered plants with enhanced resilience to abiotic stresses. These findings hold significant promise for agricultural practices, especially in regions facing soil salinity, helping ensure food security in challenging environments.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhae280
Funding information
This work was supported by National Natural Science Foundation of China (32372698, 32072575), Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX22_0752), and National Vegetable Industry Technology System (CARS-23-A16) to T.L., and the USDA National Institute of Food and Agriculture (NIFA) Hatch project 02913 to W.L.
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.
Journal
Horticulture Research
Subject of Research
Not applicable
Article Title
BcWRKY25-BcWRKY33A-BcLRP1/BcCOW1 module promotes root development for improved salt tolerance in Bok choy
Starving for sugar: how grape cells adapt by rewriting their epigenome
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Global DNA-methylation is affected in G- cells. Global methylation level analysis in G− and G+ condition. (A) Bart chart representing the methylation level of individual sample (y-axis, 1 = 100%) in the three-cytosine sequence context (x-axis). (B, C) Cytosine methylation profiles within and 2 kb up- and downstream of (B) genes coding sequence and (C) of TE. (D) Differentially Methylated Cytosines (DMCs) and Differentially Methylated Regions (DMRs) and their contexts in G− condition compared to G+. Grey bar chart represents the total number of DMC/DMRs identified. Methylation changes are represented in black when methylation increases in G− compared to G+ cells (Hyperme) and in light grey when methylation decreases in G− compared to G+ cells (Hypome). Number of DMCs and DMRs are indicated on the top/bottom of each barchart. (E) Localization of identified DMRs in specific genomic features. Black and white pie charts represent the proportion of hyper-(black) and hypo-(white) methylated of identified DMRs (number underneath) in each sequence context. TE: extragenic transposable elements; TE-intron: intronic transposable elements; TE-promoter; transposable element found within promoter sequence.
view moreCredit: Horticulture Research
A recent study reveals how grapevine cells adapt to sugar starvation by reprogramming their DNA methylation and gene expression. Under carbon-deficient conditions, these cells undergo significant metabolic shifts, slowing growth while activating survival mechanisms like autophagy and photosynthesis. The research highlights the critical role of epigenetic changes, particularly increased DNA methylation at transposable elements, in helping cells cope with energy stress. These findings deepen our understanding of plant resilience and could inform strategies to improve crop tolerance to environmental stresses, such as drought or nutrient scarcity.
Plants face constant challenges from fluctuating nutrient availability, which disrupts their growth and survival. Sugar starvation, for instance, triggers metabolic and transcriptional changes, but the role of epigenetic regulation in this process remains poorly understood. Epigenetic mechanisms, such as DNA methylation, are known to influence gene activity without altering the DNA sequence, yet their connection to metabolic stress is unclear. Previous studies in animals and yeast have linked starvation to epigenetic modifications, but evidence in plants is limited. Understanding how plants epigenetically adapt to carbon scarcity could unlock new ways to enhance their stress resilience. Based on these challenges, researchers investigated the interplay between sugar depletion, DNA methylation, and gene expression in grapevine cells.
Published (DOI: 10.1093/hr/uhae277) on January 1, 2025, in Horticulture Research, a study by scientists from the University of Bordeaux and INRAE, including Margot M.J. Berger, Virginie Garcia, Nathalie Lacrampe, and others,explores how grapevine cells respond to sugar starvation. Using Cabernet Sauvignon cell cultures, the team analyzed metabolic, transcriptional, and epigenetic changes under glucose-rich and glucose-poor conditions. The research reveals that carbon deficiency triggers widespread DNA methylation changes, particularly at transposable elements, alongside shifts in gene expression linked to stress survival. These findings underscore the importance of epigenetic regulation in plant adaptation to nutrient scarcity.
The study found that grapevine cells deprived of glucose halted growth within 48 hours and underwent dramatic metabolic reprogramming. Key pathways for biomass production, like cell wall synthesis, were downregulated, while autophagy and photosynthesis genes were activated. Notably, sugar-starved cells showed higher global DNA methylation levels, especially in transposable elements, suggesting a mechanism to stabilize the genome under stress.
Using multi-omics approaches, the team identified 5,607 differentially expressed genes and 848 differentially methylated regions (DMRs). Hyper-methylation in CHH contexts was prominent, linked to reduced cell division and altered small RNA pathways. Intriguingly, some genes involved in carbon metabolism and stress responses exhibited methylation changes in their promoters, correlating with expression shifts. For example, a malate dehydrogenase gene was repressed alongside hyper-methylation of its promoter.
The study also revealed disruptions in one-carbon metabolism, which supplies methyl groups for DNA methylation. Flux analyses showed slowed production of S-adenosylmethionine (SAM), a key methyl donor, hinting at resource reallocation during starvation. These insights highlight how epigenetic and metabolic networks jointly orchestrate plant stress responses.
Dr. Philippe Gallusci, the study’s corresponding author, emphasized: "Our work bridges the gap between metabolism and epigenetics in plants. By showing how DNA methylation dynamically responds to carbon scarcity, we uncover a layer of regulation critical for stress adaptation. This could pave the way for breeding crops with enhanced resilience by targeting epigenetic pathways."
The research opens avenues for improving crop tolerance to abiotic stresses, such as drought or poor soil, by manipulating epigenetic markers. Farmers could potentially use metabolic priming or epigenetic editing to enhance plant survival in low-nutrient conditions. Additionally, the findings may inform viticulture practices, helping grapevines withstand climate-induced sugar shortages during ripening. Future studies could explore whether similar mechanisms operate in other crops or under field conditions. By elucidating the epigenetic basis of stress responses, this work contributes to sustainable agriculture strategies aimed at securing food production in a changing climate.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhae277
Funding information
Margot Berger was in receipt of a grant financed by CNIV (Comité National des Interprofessions du Vin) and by the Région Nouvelle Aquitaine (EPISTORE). Bernadette Rubio was in receipt of the PNDV (Plan National du dépérissement de la Vigne) funding EPIDEP. The work was supported by PNDV, Region Nouvelle Aquitaine and Bordeaux University.
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.
Journal
Horticulture Research
Subject of Research
Not applicable
Article Title
Grapevine cell response to carbon deficiency requires transcriptome and methylome reprogramming
