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Biomedical subjects

Yuyang Zhang

Publications and source records attributed to Yuyang Zhang.

5 recordsLinked to original sources

The TANG cluster comprising ten nitrate transporter genes controls fruit sweetness and size in tomato.

Sucrose is a major transport form of photoassimilated carbon in tomato, Arabidopsis, and many other plant species, and plays a critical regulatory role in plant growth, development, and fruit quality. Plant vacuoles function as storage organelles, accumulating substantial quantities of metabolically inactive nitrates as a nitrogen reserve and soluble sugars as a carbon reserve. Consequently, the balance between nitrate and sucrose accumulation determines plant growth dynamics and fruit taste. In this study, we identified a gene cluster designated TANG (Total soluble solidsAccumulation viaNitrate transporterGene cluster), comprising ten nitrate transporter genes that are significantly associated with sucrose accumulation in tomato. This gene cluster mediates the transport of nitrate between the cytoplasm and vacuole, thereby influencing its storage. Functional disruption of TANG8, a member of the gene cluster, results in either enhanced sugar accumulation or increased fruit size. Selective disruption of multiple TANG cluster members yields fruits with elevated sweetness and increased fruit size in S. pimpinellifolium. The interaction between the TANG members and a tonoplast localized Sucrose Transporter 4 provides insight into the competitive accumulation of nitrate and sugar. The multiplex editing of a gene cluster provides a successful example of engineering crops with high quality and yield.

Gene cluster

Activity-dependent DNA methylation and demethylation: epigenetic regulators of learning and memory.

Learning and memory are fundamental cognitive processes that rely on activity-dependent epigenetic mechanisms to shape synaptic and neuronal plasticity. Among these, DNA methylation and demethylation have emerged as pivotal regulators that convert transient neural activity into enduring transcriptional programs. In mammals, DNA methylation marks include 5-methylcytosine (5mC) as well as the less well-established N6-methyladenine (6mA) and the more enigmatic N4-methylcytosine (4mC). Compared with 5mC, the abundance, genomic distribution, and regulatory role of 6mA and 4mC remain incompletely defined, partly due to low abundance and technical challenges, yet these non-canonical marks may provide an additional regulatory layer in specific biological contexts. Accordingly, this review focuses on the best-characterized pathway in the nervous system, 5mC and its activity-regulated oxidative turnover. This system comprises a dynamic spectrum of cytosine modifications, including 5mC, 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC), orchestrated by distinct enzyme families such as DNMTs, TETs, and TDG. We review current insights about how these regulators shape activity-induced gene expression programs underlying learning and memory, and we discuss how dysregulated DNA (de) methylation contributes to impaired transcriptional control and cognitive decline in neurodegenerative diseases, particularly Alzheimer's disease. Finally, we highlight recent advances in high-resolution mapping technologies for DNA modifications, which are expanding our ability to resolve cell type- and locus-specific epigenetic dynamics in the brain. A deeper understanding of these pathways may inform targeted strategies to preserve or restore cognitive function in neurological disorders.

Alzheimer’s disease

A smartphone-integrated Pt@Cu-HCF nanozyme-based paper sensor for on-site determination of total antioxidant capacity in marine oils.

Total antioxidant capacity (TAC) serves as a key indicator for evaluating the nutritional quality of foods. In this study, we designed a platinum-embedded copper hexacyanoferrate (denoted as Pt@Cu-HCF) nanozyme that exhibits high oxidase-like activity, efficiently catalyzing the oxidation of chromogenic substrates to generate robust colorimetric signals. Antioxidants quench hydroxyl radicals (∙OH) produced during the catalytic process, leading to a concentration-dependent suppression of the color signal. Leveraging this mechanism, a smartphone-integrated, colorimetric paper sensor for on-site TAC quantification was developed, using vitamin E as the calibration standard. The sensor was applied to determine TAC in fish oil, algal oil, and krill oil, demonstrating a linear response range of 9.78-312.5 μM and a limit of detection (LOD) of 6.41 μM. Validation using real-world marine oil samples showed excellent agreement with a commercial assay kit, confirming the reliability and practical applicability of this portable sensor for TAC measurement in complex biological matrices.

Antioxidants

Comparative effectiveness and safety of pharmacological interventions for sleep outcomes in chronic non-cancer pain: a systematic review and network meta-analysis.

Sleep disturbances are highly prevalent among individuals with chronic non-cancer pain and are associated with worse pain severity and poorer prognosis. The comparative trade-offs between the effectiveness and safety of available pharmacotherapies for sleep outcomes in this population remain poorly defined. Ninety-eight RCTs involving 28,920 participants (mean age 53.2 years, 71.2% female) were included. Moderate-certainty evidence demonstrated that melatonin significantly improved sleep quality compared with placebo (standardized mean difference [SMD] = -0.60, 95%CI: -0.98, -0.22). Ten agents (e.g., amitriptyline, oxycodone, gabapentin, pregabalin, duloxetine) also showed statistically significant improvements in subjective sleep quality (SMD = -0.24 to -1.07), but most effects were supported by low-certainty evidence and were accompanied by an increased risk of adverse events (odds ratio [OR] = 1.90 to 37.00). Conversely, melatonin was not associated with an increased risk (OR = 0.88, 95%CI: 0.19, 3.94). Our findings indicate that melatonin shows promise as a safe, adjunctive option for improving sleep quality in this population, but larger, condition-specific trials are warranted to confirm these effects. Other pharmacological agents are limited by lower-certainty and unfavorable safety profiles. These results should be interpreted cautiously given limited direct comparisons, heterogeneous chronic pain populations, the high proportion of trials at high risk of bias, and the predominance of subjective sleep outcomes.

Humans

Ethylene response factors ERF.B2 and ERF.B5 synergically regulate ascorbic acid biosynthesis at multiple sites in tomato.

Ascorbic acid (AsA) is an important growth regulator and antioxidant in plants. It is acknowledged as a quality indicator in tomato (Solanum lycopersicum). Although the AsA biosynthetic pathway has been elucidated, its regulatory mechanisms remain largely unknown. In the present study, two members of the ethylene response factor (ERF) family, SlERF.B2 and SlERF.B5, were found to be co-expressed with SlGGP1, a pivotal gene in AsA biosynthesis. These two transcription factors were biochemically confirmed to bind to the DRE motif (GCCGAC/GTCGGC) of the SlGGP1 promoter. Notably, the SlERF.B2 and SlERF.B5 functioned as a dimer to regulate SlGGP1 expression and AsA biosynthesis. Overexpression of SlERF.B2 and SlERF.B5 enhanced the AsA levels up to 149 and 140%, respectively, whereas knockout of either of them could significantly decrease the AsA levels by up to 27%. DNA affinity purification sequencing (DAP-seq) indicated that SlERF.B2 synergistically regulates AsA biosynthesis at multiple sites by targeting the promoters of SlGPI and SlDHAR1. Overexpression of SlERF.B2 or SlERF.B5 in tomato conferred a high capacity for scavenging reactive oxygen species and enhanced tolerance to oxidation and salt stress, potentially by elevating the AsA content. This study unravels novel regulators of AsA biosynthesis and elucidates a molecular network that should facilitate the improvement of this nutrient in tomato and enhance stress tolerance in plants.

Solanum lycopersicum