These findings demonstrate that GmHMGR6 enhances soybean salt tolerance through coordinated regulation of nitrogen metabolism, nodulation, and photosynthetic performance.
The GmSNAT1 gene, which encodes a key enzyme involved in soybean melatonin biosynthesis, is crucial for abiotic stress tolerance. In the present study, the molecular mechanism by which GmSNAT1 enhances cold tolerance is elucidated. The cold tolerance of plants was significantly increased by GmSNAT1 overexpression and reduced by CRISPR/Cas9-mediated knockout, a phenotype that was effectively rescued by exogenous melatonin. Integrated transcriptomic, physiological, and biochemical analyses revealed that the GmSNAT1-mediated melatonin pathway activates calcium signaling; coordinates the crosstalk between auxin, abscisic acid, and ethylene; and mobilizes transcription factor networks to orchestrate bidirectional physiological responses. Additionally, the activation of antioxidant systems for reactive oxygen species scavenging and the upregulation of photosynthesis-related genes to maintain photosynthetic stability were explored. The physical interaction between GmSNAT1 and the plant sulfotyrosine peptide receptor GmPSYR1 was confirmed using co-immunoprecipitation, bimolecular fluorescence complementation, and yeast two-hybrid assays. This interaction may be involved in cold stress signal transduction, regulation of root development, and redox homeostasis through GmPSYR1. Collectively, these findings demonstrate that cold adaptation in soybeans is synergistically enhanced by GmSNAT1 via a multidimensional axis encompassing melatonin synthesis, signal transduction, and physiological protection, thereby providing a novel molecular target for breeding cold-tolerant crops.
C. Ren, Tong Cheng, Wenjie Zhang et al.· Plant Physiology· 0 citations
Drought stress is a primary abiotic constraint limiting potato productivity. While polyphenol oxidase (PPO) is known to participate in stress responses, the specific role of StuPPO9 in drought tolerance remains poorly understood. In this study, we generated StuPPO9-overexpressing (OE) and CRISPR/Cas9-mediated knockout (C4) lines in the potato cultivar ‘Atlantic’. Under sustained drought stress, OE lines exhibited significantly superior growth phenotypes compared to wild-type (WT) and C4 plants, characterized by increased leaf and root relative water content, root number and enhanced photosynthetic efficiency (Pn and Gs). OE plants also maintained lower levels of MDA and ROS through elevated antioxidant enzyme activities. Notably, transcriptomic analysis revealed that StuPPO9 triggers a global reprogramming of metabolic pathways. Key drought-responsive genes associated with phenylpropanoid biosynthesis (e.g., anthocyanin acyltransferase), terpenoid metabolism, and hormone signaling (e.g., HPt protein) were significantly upregulated in OE plants. These findings suggest that StuPPO9 confers drought resilience through a multi-layered network involving optimized carbon allocation, reinforced cell wall integrity, and enhanced ROS scavenging capacity. This study provides a promising genetic target and theoretical foundation for breeding drought-resistant potato varieties.
Ming-Kun Chi, Boyang Liu, Heng-Zhao Yang et al.· Plants· 0 citations
Water scarcity impacts soybean cultivation and productivity globally. The ability of plants to withstand drought stress involves complex molecular and physiological mechanisms that facilitate the restoration and maintenance of cellular homeostasis. This study identified genes associated with carbohydrate metabolism and GABA shunt pathway that respond to water deficit in two soybean varieties. These varieties exhibited contrasting responses to water scarcity, and were subjected to two distinct cropping systems. In the drought-tolerant variety, a strategy for conferring tolerance was observed through the pre-emptive priming of the drought response. By applying multivariate analysis, we identified a pivotal gene, GmBAM-like 1, which responds to water scarcity. GmBAM-like 1 encodes a β-amylase and showed rapid activation and elevated expression levels in root tissues of the tolerant variety, suggesting its potential involvement in the drought tolerance response. Transgenic Arabidopsis plants overexpressing GmBAM-like 1 demonstrated enhanced tolerance to salt and osmotic stress, as evidenced by increased survival and germination rates. Additionally, after drought stress, these plants showed higher transpiration rates, larger leaf area, and greater relative water content upon rehydration. These findings demonstrate the potential of integrating the GmBAM-like 1 gene into plant breeding programs to develop cultivars with improved tolerance to water, salt, and osmotic stresses.
Fábia Guimarães-Dias, Lucas Leal Lima, A. C. Neves-Borges et al.· Genetics and Molecular Biolo...· 0 citations
ABSTRACT Strigolactones (SLs) modulate multiple aspects of plant development and stress physiology. This study investigated their role in maize response to abiotic stress by comparing an SL‐biosynthesis mutant (zmccd8) with wild‐type (WT) seedlings grown for 4 weeks in vermiculite under nutrient and water limitation. Plant growth, time‐course pigment accumulation, targeted gene expression, and root transcriptomic profiles were analyzed. Our results showed that zmccd8 plants were largely unable to induce leaf senescence and efficient nutrient remobilization toward younger tissues under nitrogen (N) deficiency, a response previously associated with maize adaptation to low N availability. In parallel, the mutant developed a smaller root system, mainly due to limited adventitious root formation, particularly under N shortage. Root transcriptomic profiling revealed that N deficiency strongly affected WT plants, inducing extensive regulation of pathways involved in nitrogen metabolism and transport, secondary metabolism, ethylene and MAPK signaling, oxidative stress responses, and major transcription factor families. These responses were largely absent in the zmccd8 mutant, suggesting reduced transcriptional plasticity and compromised capacity to cope with stress‐associated oxidative imbalance. Conversely, despite inducing substantial physiological and molecular responses, water stress elicited only modest SL‐dependent regulation, with limited and heterogeneous changes between genotypes. Overall, our findings demonstrate that in maize, SLs act in a stress‐specific manner, playing a predominant role in acclimatisation to nitrogen deficiency through coordinated regulation of senescence, nutrient remobilization, root architecture, and gene expression, while contributing more marginally to water‐stress acclimatisation. These results provide new insights into SLs' role in shaping maize physiological plasticity under abiotic stress conditions.
L. Buzzicotti, Claudia Camilletti, L. Ravazzolo et al.· Physiologia Plantarum : An I...· 0 citations
Soil inorganic nitrogen (N) availability is a critical determinant of symbiotic nitrogen fixation efficiency, making it essential for legumes to respond appropriately and effectively to N fluctuations. Here, we identify a pair of high N response factors GmNIGT2a/2b (NITRATE-INDUCIBLE GARP-TYPE TRANSCRIPTIONAL REPRESSOR). GmNIGT2a/2b are activated by GmNLP4a/b (NIN-like proteins) under high N. The nodules of gmnigt2a/2b double mutants exhibit exacerbated reduction in nitrogenase activity and accelerated senescence in response to high N. Integration of RNA-seq and DAP-seq analyses reveals that GmNIGT2a/2b negatively regulate a suite of core N-induced genes, including NAC, WRKY, and bZIP transcription factors as well as trehalose metabolism genes. GmNIGT2b binds to the promoters of SNAP3 and NAC039 and represses their expression, thereby delaying nodule senescence. Our results suggest that GmNIGT2a/2b-mediated transcriptional regulation prevents excessive nodule senescence in response to high N, highlighting the complexity of transcriptional reprogramming for environmental adaptation in nodules.
Tianli Ge, Xiaolei Yao, Yuan Li et al.· Journal of genetics and geno...· 0 citations
The results suggest that OsCYP51H9 participates in the phytosterol-BR pathway and plays a positive role in rice adaptation to low-nitrogen environments, providing a potential target for molecular breeding.
Zhengli Jiao, Jianyi Li, Weijuan Xu et al.· Plant physiology and biochem...· 0 citations