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Biomedical subjects

Shan Jiang

Publications and source records attributed to Shan Jiang.

6 recordsLinked to original sources

Phylogenetic Constraints and Environmental Filtering Jointly Drive Adaptive Evolution in Phragmites australis: From Genetic Structure to Trait Decoupling on the Mongolian Plateau.

The Mongolian Plateau, a typical arid and semi-arid zone in Eurasia, is characterized by highly heterogeneous and fragmented wetland habitats. Phragmites australis, a common wetland species in this region, exhibits remarkable adaptability. Unraveling the coordination between phylogenetic history and local environmental filtering is crucial for elucidating its adaptive mechanisms. Integrating landscape genomics and trait-based phylogenetic analyses, we analyzed transcriptome-wide SNPs, multidimensional functional traits, and environmental variables across 90 individuals from 30 natural P. australis populations. This study aims to reveal the genetic and phenotypic variation patterns underlying population genetic structure and trait variation, specifically distinguishing the roles of geographic isolation, environmental filtering, and phylogenetic history. Results reveal a significant drainage-dependent pattern in genetic structure. Populations in hydrologically connected basins show extensive admixture, whereas those in isolated endorheic basins form distinct lineages. While geographic isolation underpins genetic differentiation, environmental filtering independently explains ~33.84% of the genetic variation, driven primarily by moisture heterogeneity (precipitation seasonality and soil moisture). Crucially, we observed differentiated evolutionary trajectories across functional traits. Structural traits (e.g., plant height, leaf thickness) are phylogenetically conserved; in contrast, physiological traits (e.g., water use efficiency) are decoupled from phylogeny, showing patterns consistent with high plasticity regulated by local environments. This evolutionary decoupling strategy enables P. australis to flexibly adapt to heterogeneous habitats while maintaining structural stability. This study uncovers the synergistic mechanisms by which geographic isolation and environmental filtering jointly shape the genetic patterns of this cosmopolitan species at a regional scale, clarifies that its evolutionary responses may depend heavily on the differentiated plasticity of trait types, and provides valuable regional insights into how widespread wetland species adapt to heterogeneous environments under global change.

Mongolia Plateau

Day + 30 detection of minimal residual FLT3-ITD by high-sensitivity PCR-NGS predicts relapse risk and guides post-transplant maintenance in AML.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved outcomes in patients with acute myeloid leukemia (AML) harboring FLT3-internal tandem duplication (FLT3-ITD) mutations. However, relapse still occurs in 15-35% of these patients after transplantation. Therefore, early and highly sensitive detection methods are required to identify patients at risk of relapse and enable timely post-transplant intervention. METHODS: In this NICHE cohort study, a total of 136 patients were included, then we evaluated whether high-sensitivity polymerase chain reaction (PCR)-next-generation sequencing (NGS) for FLT3-ITD (limit of detection: 5 × 10-6) on day + 30 post-HSCT could identify patients at a high risk of relapse and inform decisions regarding maintenance therapy. RESULTS: Among the 136 patients, 37 patients (27.2%) had detectable FLT3-ITD clones on day + 30. These patients exhibited a significantly higher cumulative incidence of post-HSCT multiparameter flow cytometry (MFC)-measurable residual disease (MRD) relapse (40.3% vs. 18.8%, p = 0.001). Notably, FLT3-ITD-positive patients who received FLT3 inhibitor maintenance therapy had no relapses, while 6 out of the 13 patients who did not receive maintenance therapy relapsed. Conversely, FLT3-ITD-negative patients without high-risk factors (2022 European LeukemiaNet adverse-risk group, relapsed/refractory AML, MFC-MRD positivity pre-HSCT) showed limited benefit from maintenance therapy (MFC-MRD-free survival: hazard ratio (HR) = 0.25 (0.03-2.11), p = 0.204; OS: HR = 0.20 (0.02-1.70), p = 0.142). CONCLUSIONS: This is the first study to demonstrate that detection of minimal FLT3-ITD clones at the fixed time point of day + 30 post-HSCT can reliably stratify relapse risk in AML patients and provide a rationale for individualized post-transplant maintenance therapy.

Humans

GFER Represents a Target for Dual Disruption of Redox Homeostasis and Reactivation of the Immune Response in Pancreatic Adenocarcinoma.

UNLABELLED: Both metabolic dysregulation and the immunosuppressive tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC) contribute to the recalcitrance of this lethal disease to treatment. Accordingly, we aimed to identify and characterize a target that elicits an anticancer response through both disrupting cancer cell redox homeostasis and increasing the immunogenicity of PDAC. First, mitochondrial metabolic dependencies in PDAC were identified by using a CRISPR-Cas9 screening system with a custom single-guide RNA library. Functional validation analyses revealed GFER, a mitochondrial FAD-dependent sulfhydryl oxidase, as an essential regulator of tumor growth. In vitro and in vivo methodologies demonstrated that GFER depletion perturbed redox homeostasis and stimulated tumor immunogenicity, including sensitization to immune checkpoint blockade. In patient-derived xenograft models of PDAC, the growth-inhibitory response induced by GFER depletion was mediated by an altered oxidative balance that released damaged mitochondrial DNA into the cytoplasm of tumor cells, leading to the activation of the cGAS-STING pathway and expression of type I IFNs. This effect was recapitulated in a mouse immunocompetent syngeneic PDAC model, in which GFER depletion suppressed tumor growth and promoted T-cell infiltration to enhance tumor-killing effects. Consequently, GFER depletion significantly increased the antitumor efficacy of immune checkpoint blockade. Overall, these findings identify GFER as a critical node for both mitochondrial redox homeostasis and immunomodulation in PDAC and reveal a therapeutic opportunity for sensitizing PDAC to immune checkpoint blockade. SIGNIFICANCE: GFER is essential for mitochondrial redox balance and suppressing tumor immunogenicity in pancreatic tumors, with the combination of GFER inhibition with immune checkpoint blockade resulting in a strong antitumor response.

Animals

[Mechanism of Tianshu Capsules in treating migraine rats based on gut microbiota].

This study aims to investigate the therapeutic effect of Tianshu Capsules(TS) on migraine rat model and explore its potential mechanism of action from the perspectives of the structure of the gut microbiota and functional pathway regulation. A migraine rat model was established via subcutaneous injection of nitroglycerin. The Sprague-Dawley rats were randomly divided into a control group, a model group, a low-dose TS group, a medium-dose TS group, a high-dose TS group, and an ibuprofen group. The efficacy of TS in improving migraine was evaluated by general condition observation and measurement of the craniofacial pain threshold. The expression of the gene c-fos in the trigeminal ganglion was determined by quantitative real-time polymerase chain reaction(PCR). The contents of endothelin-1(ET-1), calcitonin gene-related peptide(CGRP), and 5-hydroxytryptamine(5-HT) in serum were measured by enzyme-linked immunosorbent assay(ELISA). Fecal samples were subjected to metagenomic sequencing for systematic analysis of gut microbial diversity, taxonomic composition difference, and functional pathway changes of Kyoto Encyclopedia of Genes and Genomes(KEGG), and their correlations with behavioral and biochemical indices were further evaluated. The results show that TS significantly improves the increased body temperature and decreased craniofacial pain threshold in migraine rats. It also markedly suppresses the elevated expression levels of the gene c-fos in the trigeminal ganglion and reduces the levels of ET-1, CGRP, and 5-HT in serum. Metagenomic beta diversity analysis and differential taxonomic abundance analysis reveal that the migraine model induces significant gut microbiota dysbiosis, characterized by enrichment of harmful genera, including Streptococcus and Enterococcus, as well as a decline in the abundance of beneficial bacteria such as Allobaculum, Eubacterium, and Muribaculum. Functional pathway analysis results of KEGG further reveal that the relative abundances of pathways associated with biosynthesis of phenylalanine, tyrosine, and tryptophan, bacterial secretion system, citrate cycle, and biosynthesis of secondary metabolites are significantly decreased in the model group. TS intervention increased the abundance of the genus, such as Parabacteroides, Eubacterium, Allobaculum, and Muribaculum, while decreasing levels of microbiota, including Staphylococcus. TS also significantly upregulated pathways associated with barrier function(tight junction), amino acid biosynthesis pathways, and biosynthesis pathways of neurotransmitter precursors such as cysteine and methionine metabolism. In addition, it downregulated inflammatory pathways(Toll and IMD signaling) and pathways related to Staphylococcus aureus infection, thereby restoring the structure and function of the microbiota to a state close to those of the normal group. Spearman correlation analysis reveals that partial gut microbiota are significantly associated with migraine-related behavioral and biochemical indices(c-fos, ET-1, CGRP, and 5-HT). In conclusion, TS can regulate the disrupted gut microbiota structure and microbial functions related to neurotransmitter metabolism, intestinal barrier function, and inflammatory regulation in migraine model rats, which may be one of the potential key ways through which TS exert its anti-migraine effect.

Animals

RcAP2L-RcAS1 complex modulates petal number in roses by targeting RcAGL80 promoter.

Double flower, which is one of the most important characteristics of ornamental plants, is closely related to their ornamental and commercial value. The double-flower trait in rose was mainly due to the increase in petal number caused by stamen petalization. However, the mechanism regulating petal number is not clear. In this study, the Rosa chinensis "Zhaiye Tengben Yuejihua" × R. chinensis "Old Blush" population was used for QTL detection and NGS-based BSA analysis to identify candidate genes related to petal number. It was found that RcAP2L and RcAS1 were highly expressed in double-flower rose, while RcAGL80 was highly expressed in single-flower rose. Silencing RcAP2L and RcAS1 reduced the petal number by inhibiting homeotic conversion of stamens to petals, separately. However, silencing RcAGL80 increased the petal number by promoting homeotic conversion of stamens to petals. The results of Y2H and BiFC assays showed that RcAP2L interacted with RcAS1. The dual-luciferase assay showed that RcAP2L was bound to the promoter of RcAGL80 and suppressed RcAGL80 transcription. In total, we found a new function of AS1 in specifying flower organ identity, and a new pathway for regulating the number of petals by RcAS1, RcAGL80, and RcAP2L, which provides new information for elucidating the mechanism of the formation of double flower in rose.

Rosa