Stress biology最新文献

As a barrier between the cell and its environment, the plant cell wall provides structural support during development and stress response. Plants are able to sense their surroundings and adjust their activities accordingly. A crucial mechanism involved in these adaptive changes is the cell wall integrity (CWI) maintenance mechanism, which monitors and maintains the integrity of cell walls via changes in cell and cell wall metabolism without destroying cell wall organization. Different abiotic stresses and changes in plant developmental phases disrupt CWI. However, emerging evidence has demonstrated the initiation of CWI signaling mechanisms as key in promoting plant growth in complex situations. This review discusses recent advances in the Catharanthus roseus receptor-like kinase 1-like (CrRLK1L) protein function in plant cell wall signaling during adaptation to changing environments and development. We conclude by highlighting how current spatially resolved transcriptomics may be used to advance the role of CrRLK1L members in plant cell wall signaling during development and stress response.

Sheath blight (ShB), caused by the necrotrophic fungus Rhizoctonia solani, is a globally destructive rice disease responsible for significant yield losses. However, the absence of characterized genes conferring high potential resistance to sheath blight within natural rice germplasm constrains resistance breeding. A recent study published in Nature Genetics uncovered the ShB resistance receptor-like kinase 1 (SBRR1) as a key gene associated with disease resistance. SBRR1-R, an elite resistance allele mainly presented in indica rice and distinguished by a 256-bp promoter insertion, confers strong resistance without obvious yield penalty. SBRR1 is the first gene with major effects underlying natural variation in sheath blight resistance, offering significant potential for rice breeding. Furthermore, the discovery of the "bHLH57-SBRR1-R-SIP1-Chit3/4" defense module provides fundamental insights into rice immunity and a molecular module with substantial breeding potential.

Heavy metal pollution severely impacts plant health by inhibiting growth, photosynthesis, enzyme activities, and causing oxidative stress. Plants respond to such stress by activating complex defense mechanisms involving reactive oxygen species and different signaling pathways. These pathways are pivotal in triggering plant defense responses and are currently a major focus of research. Understanding the complex mechanisms of heavy metal uptake, transport, chelation, and signaling can guide strategies to improve plant resilience and stress tolerance. In this review, we aim to highlight the key heavy metals found in soil and the environment, along with their mechanisms of accumulation in plants. We also explore the defense responses of plants through various signaling pathways such as calcium (Ca²⁺), MAP kinase, and hormone signaling. Additionally, we emphasize the importance of understanding advanced omics technologies, including transcriptomics, metabolomics, and bioinformatic tools, in enhancing our knowledge of plant resilience and stress tolerance.

Plant cells exhibit an extraordinary regenerative potential, achieving cellular totipotency by dedifferentiating to form new tissues. While significant progress has been made in understanding cell fate mechanisms, the regulatory networks governing callus cell development remain insufficiently explored, particularly regarding cell classification, morphology, and regulatory processes. This study provides a detailed investigation into the developmental dynamics and transcriptomic profiles of callus cells in Arabidopsis at key stages: initiation, proliferation, and greening. Employing single-cell RNA sequencing and UMAP-based clustering, we annotated cell clusters based on highly enriched gene expressions. Developmental trajectories were further mapped through pseudotime analysis, revealing distinct transcription factor networks. Additionally, functional analysis of key regulatory genes was conducted using mutant and overexpression lines, affirming their roles in callus development. Gene Ontology analysis highlighted the involvement of environmental factors-low oxygen and salinity promoted callus formation, while light inhibited it, though essential for greening. These findings shed light on the complex regulatory landscape of plant tissue regeneration and guide future research avenues.

Understanding the genetic mechanism of cold adaptation in cashmere goats and dairy goats is very important to improve their production performance. The purpose of this study was to comprehensively analyze the genetic basis of goat adaptation to cold environments, clarify the impact of environmental factors on genome diversity, and lay the foundation for breeding goat breeds to adapt to climate change. A total of 240 dairy goats were subjected to genome resequencing, and the whole genome sequencing data of 57 individuals from 6 published breeds were incorporated. By integrating multiple approaches such as phylogenetic analysis, population structure analysis, gene flow and population history exploration, selection signal analysis, and genome-environment association analysis, an in-depth investigation was carried out. Phylogenetic analysis unraveled the genetic relationships and differentiation patterns among dairy goats and other goat breeds. Through signal analysis (θπ, FST, XP-CLR), we identified numerous candidate genes associated with cold adaptation in dairy goats (STRIP1, ALX3, HTR4, NTRK2, MRPL11, PELI3, DPP3, BBS1) and cashmere goats (MED12L, MARC2, MARC1, DSG3, C6H4orf22, CHD7, MYPN, KIAA0825, MITF). Genome-environment association (GEA) analysis confirmed the link between these genes and environmental factors. Moreover, a detailed analysis of the critical genes C6H4orf22 and STRIP1 demonstrated their significant roles in the geographical variations of cold adaptation and allele frequency differences among different breeds. This study contributes to understanding the genetic basis of cold adaptation, providing crucial theoretical support for precision breeding programs aimed at improving production performance in cold regions by leveraging adaptive alleles, thereby ensuring sustainable animal husbandry.

Nucleotide-binding leucine-rich repeat (NLR) proteins assemble into genetically linked pairs to mediate effector-triggered immunity (ETI) in plants. Here, we characterize the paired NLRs NRCX and NARY (NRCX adjacent resistance gene Y) in Nicotiana benthamiana. CRISPR/Cas9 knockout of NRCX caused severe dwarfism and constitutively activated immunity, marked by PR1 upregulation and enhanced resistance to Phytophthora capsici. Co-silencing or double knockout of the adjacent NLR NARY partially rescued the nrcx phenotype, revealing NARY as a compensatory regulator that modulates growth and immunity. Structural analysis revealed that NARY harbors non-canonical Walker B and MHD motifs, which lack autoactivation capacity despite their divergence from canonical NLR executors. Split-luciferase and co-immunoprecipitation assays showed that NRCX and NARY interact exclusively through their CC domains, forming a non-canonical regulatory complex. Notably, simultaneous silencing of NRC2/3 and NARY incompletely restored growth in nrcx mutants, implicating additional factors in immune modulation. Our findings establish NARY as a compensatory NLR partner of NRCX that fine-tunes immunity without triggering cell death, revealing a novel mechanism for balancing growth and defense in Solanaceae.

Environmental stress adaptation is crucial for the survival and pathogenicity of plant fungal pathogens. In this study, we identified a transcription factor FgMsn2 in Fusarium graminearum, an ortholog of Msn2 in budding yeast. Structural analysis showed that the C2H2 zinc-finger domain is highly conserved across fungi, while other regions are less conserved, suggesting that FgMsn2 may have species-specific functions. Subsequently, we revealed that FgMsn2 is critical for vegetative growth, and conidiogenesis. Deletion of FgMSN2 severely reduced the deoxynivalenol (DON) production and pathogenicity, while enhancing tolerance to oxidative, osmotic, cell wall and membrane stresses. Furthermore, our RNA-seq analysis revealed that FgMsn2 regulates genes involved in energy metabolism, lipid metabolism and stress responses, emphasizing its role in maintaining metabolic balance and stress adaptability. Notably, FgMsn2 influences mitochondrial morphology, as the Fgmsn2 mutant exhibited disrupted mitochondrial structures and reduced ATP production. The Fgmsn2 mutant also showed increased lipid droplet accumulation, indicating the FgMsn2's role in lipid metabolism. Taken together, the FgMsn2 serves as a key regulator in fungal development, plant infection, stress responses, and metabolism. Our study provides valuable insights into the molecular mechanisms of fungal stress adaptation and pathogenicity, suggesting a potential target for the development of more effective fungicides and disease management strategies.

Cucumber target spot, a major disease that threatens cucumber production, is caused by Corynespora cassiicola. Cyclobutrifluram, a novel succinate dehydrogenase inhibitor (SDHI) developed by Syngenta, has demonstrated strong inhibitory activity against various plant pathogenic fungi and nematodes. However, its antifungal spectrum, resistance risk as well as underlying mechanisms of resistance in C. cassiicola remain poorly understood. In this study, cyclobutrifluram exhibited potent inhibitory activity against anamorphic fungi and selected ascomycetes, with the mean sensitivity of C. cassiicola isolates to the fungicide being 0.98 ± 1.26 μg/mL. Additionally, five laboratory-derived cyclobutrifluram-resistant mutants showed comparable or lower biological fitness than their respective parental isolates. The resistant mutants and field isolates were also found to possess nine distinct point mutations in the CcSdhB, CcSdhC or CcSdhD genes. Finally, cyclobutrifluram exhibited positive cross-resistance with other SDHIs, with the resistance levels varying depending on the specific mutations present. In conclusion, cyclobutrifluram was found to be effective against anamorphic fungi and selected ascomycetes. C. cassiicola's risk of resistance development to cyclobutrifluram was assessed as moderate to high and was primarily associated with mutations in CcSdh genes.

Crown rot (CR), caused by Fusarium pseudograminearum and related species, is a soil-borne disease threatening global wheat (Triticum aestivum) production, with yield losses exceeding 50% under severe infections. The rapid spread of CR in China, driven by straw retention policies and warming climates, highlights the need for interdisciplinary solutions. This review systematically integrates advances in CR research and addresses pathogen biology, host resistance, and sustainable management. Research on pathogen biology has clarified the distribution of major Fusarium species, the infection process, toxin profiles, mating types, and virulence factors. Host resistance to CR is quantitatively controlled, and through quantitative trait locus (QTL) mapping and omics-based approaches, several genes encoding transcription factors, receptor-like kinases and enzymes, signaling pathways and secondary metabolites involved in resistance have been identified. Advances in control strategies, including chemical and biological methods, as well as the application of nanotechnology, have shown promising results. The review also highlights future research directions, such as investigating the molecular mechanisms of pathogen-host interactions, identifying effectors and susceptibility genes for CR in wheat, and integrating multi-omics studies with high-resolution genetic maps to pinpoint CR resistance genes. These efforts are crucial for improving our understanding of the disease and developing effective management strategies.

Apple replant disease (ARD) poses a serious threat to apple cultivation, primarily caused by the accumulation of Fusarium species. Bacillus species have demonstrated significant potential as microbial agents, with capabilities in promoting plant growth, suppressing soil-borne pathogens, and improving soil quality. Here in this study, strain LRB-5 was isolated from a healthy apple root system and identified as Bacillus vallismortis based on physiological and biochemical characterization and molecular sequencing analysis. It exhibited broad-spectrum antifungal activity against various Fusarium species, including F. oxysporum, F. moniliforme, F. proliferatum, and F. solani, with inhibition rates exceeding 65%. LRB-5 extracellular metabolites significantly inhibited Fusarium mycelial growth and spore germination. Greenhouse experiments demonstrated that LRB-5 reduced ARD disease severity by more than 50%. The volatile organic compounds produced by LRB-5 exhibited both antimicrobial activity and growth-promoting properties. Further assays revealed LRB-5 can secrete various cell wall-degrading enzymes and possesses plant growth-promoting capabilities. Pot experiments showed LRB-5 had excellent colonization ability in the rhizosphere of Malus hupehensis Rehd. seedlings, significantly increasing seedling biomass, soil bacterial and actinomycete populations, and the activity of root protective enzymes. Moreover, LRB-5 significantly enhanced the activity of soil enzymes while reducing the contents of phlorizin, benzoic acid, and p-hydroxybenzoic acid in the rhizosphere soil. Terminal restriction fragment length polymorphism and quantitative real-time PCR analyses revealed that LRB-5 improved bacterial carbon utilization, increased microbial diversity indices, reduced the abundance of Fusarium spp., and altered the structure of soil microbial communities. Collectively, these rusults suggest that LRB-5 effectively alleviated ARD by protecting apple roots from Fusarium infection and phenolic acid toxicity, optimizing soil microbial communities, and promoting plant growth. Future research should explore the combined application of LRB-5 with other control measures, thereby promoting its practical implementation.