Mandarin fish (Siniperca chuatsi) are known to exhibit distinct physiological and immunological adaptations to environmental stressors, but the underlying molecular and microbial mechanisms remain unclear. In this study, we integrated transcriptome and microbiome analyses to investigate adaptations across three geographically distinct mandarin fish groups: Guangdong (G), Qiupu (Q), and native Taihu (T). Liver RNA sequencing revealed 5339 differentially expressed genes (DEGs) between T and G and 1531 DEGs between T and Q. Functional enrichment analysis revealed group-specific responses. Specifically, DEGs from T vs. G were linked to small-molecule metabolism and innate immunity whereas the DEGs from T vs. Q were related to immune regulation and chromatin organization. The concurrent 16S rRNA sequencing of the intestinal microbiota identified 2680 amplicon sequence variants, with principal coordinate analysis showing distinct clustering (31.77% variance). Group T had higher Firmicutes abundance whereas groups G and Q had a higher relative abundance of Fusobacteriota. Correlation networks revealed key microbe–gene interactions, including positive links between Lactobacillus and immune genes in group T and negative associations with Romboutsia. These findings suggest that enhanced immune homeostasis and metabolic flexibility in group T may result from coordinated host gene expression and Lactobacillus-driven microbiome modulation. We provide new insights into the mechanisms of adaptation in mandarin fish and identify potential biomarkers for enhancing aquaculture resilience.
UV-B radiation is a significant environmental factor that affects a wide range of biological processes in plants. Maca (Lepidium meyenii Walp.), a critical herbaceous plant native to high altitudes, shows strong adaptation to environmental stimuli including UV-B radiation. Despite the importance of maca for studying high-altitude adaptation, comprehensive transcriptomic and proteomic data on the response of maca to UV-B are lacking. This study used integrated comparative transcriptomics and proteomics to examine the gene and protein expression in maca leaves exposed to UV-B radiation for 0, 12, 24, and 36 h. As a result, 7255 significant differentially expressed genes and 257 differentially expressed proteins were identified following UV-B exposure. Bioinformatics revealed that UV-B radiation induced complex changes in the transcriptome and proteome of maca, affecting energy, carbohydrate, nucleotide, and glycan metabolism. Enrichment and protein-protein interaction network analyses highlighted the "glutathione metabolism" pathway as significantly upregulated upon UV-B radiation. Quantitative PCR of eight genes associated with this pathway revealed that seven exhibited significant transcriptional upregulation, highlighting the critical role of this pathway in maca response to UV-B radiation. Glutathione content measurement and inhibition assays demonstrated that disruption of the "glutathione metabolism" pathway led to a significant reduction in UV-B-induced total glutathione, reduced glutathione, and oxidized glutathione levels. This further supports the conclusion that the "glutathione metabolism" pathway plays a crucial role in maca's response to UV-B radiation. The transcriptomic and proteomic data presented here provide valuable insights into the functional aspects and molecular response mechanisms of maca plants to UV-B radiation.
Background: The ubiquitin–proteasome system plays a critical role in plant antiviral defense, with HECT-type E3 ubiquitin ligases serving as key regulators of protein turnover. To explore the potential involvement of the HECT gene family in host resistance against tomato yellow leaf curl virus (TYLCV), a comprehensive analysis was conducted in Nicotiana benthamiana. Methods: In this study, the HECT gene family in N. benthamiana was systematically investigated using a genome-wide bioinformatic analysis. The potential roles of these genes in the response to TYLCV infection were further examined using a virus-induced gene silencing (VIGS) technique. Results: Using a Hidden Markov Model approach, 18 NbHECT genes were identified that phylogenetically clustered into four subfamilies with distinct structural features. Chromosomal location and synteny analyses indicated that these genes were unevenly distributed across 11 chromosomes, with 10 instances of segmental duplication identified. Tissue-specific expression profiling demonstrated that 17 NbHECTs were constitutively expressed, with Group III members showing the highest expression in reproductive tissues. Following TYLCV infection, NbHECT6 was significantly downregulated while NbHECT13 was upregulated in both inoculated and systemic leaves. Functional validation through the VIGS approach revealed that suppression of NbHECT6 and NbHECT13 increased host susceptibility, as evidenced by exacerbated symptom severity and enhanced viral DNA accumulation compared to controls. Conclusions: These findings establish NbHECT6 and NbHECT13 as critical components of the plant antiviral response, providing new insights into ubiquitin-mediated defense mechanisms against geminiviruses.
The Gretchen Hagen 3 (GH3) gene family, a key component of the early auxin-responsive gene family, plays a pivotal role in regulating plant growth, development, and stress responses. However, to date, a comprehensive genome-wide analysis of the GH3 gene family and its potential role in plant defense against viruses, such as tomato yellow leaf curl virus (TYLCV), has not been conducted in Nicotiana benthamiana. Here, the GH3 gene family was thoroughly examined in N. benthamiana using a comprehensive genome-wide bioinformatic approach. A total of 25 potential GH3 genes were discovered in N. benthamiana. Phylogenetic analysis classified these NbGH3s into three different clades. Chromosomal distribution and synteny analyses revealed that NbGH3s are unevenly distributed across 14 chromosomes, with 20 segmental and one tandem duplication pairs. Promoter analysis suggested their involvement in phytohormone signaling and stress responses. Quantitative PCR showed that several NbGH3s are transcriptionally responsive to TYLCV infection, with five of them significantly upregulated in infected leaves. Furthermore, virus-induced gene silencing revealed that the suppression of NbGH3-3 and NbGH3-9 markedly increased host susceptibility to TYLCV, underscoring their critical roles in plant antiviral defense mechanisms. This research establishes a framework for understanding the functions of NbGH3s in plant growth and their response to TYLCV infection.