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Zhang, C.

Publications and source records attributed to Zhang, C..

At least 109 records · Page 6Linked to original sources

Retinoic acid resolves the conflict between X-chromosome inactivation and pluripotency program in female cleavage-stage embryos

The tight coupling of X-chromosome inactivation (XCI) and pluripotency is a paradigm of holistic developmental regulation, and their inverse correlation enables XCI establishment during implantation. In contrast, the co-establishment of imprinted XCI (iXCI) and pluripotency program in female preimplantation embryos challenges the holistic pattern, but how embryos coordinate the two remains unknown. Here, we find that Nanog during the cleavage stage strongly represses the co-upregulated Rnf12-Xist axis, the triggering signaling of iXCI, creating a conflict that threatens iXCI. We identify retinoic acid (RA) as the coordinator that resolves the conflict and safeguards iXCI. RA activates its receptor RARG to evict NANOG from Rnf12 5region, avoiding NANOGs threat. In vivo, either maternal vitamin A deficiency or embryonic RA synthesis defects results in impaired iXCI and female-biased embryonic lethality. Thus, we highlight RA as a master regulator to holistically balance iXCI and pluripotency during cleavage stages, thereby ensuring proper female embryogenesis.

developmental biology↗

Mechanism of GPR84 allosteric modulation at a helix 8-proximate site

Allosteric modulators offer opportunities for pathway-selective GPCR signalling, but the structural mechanisms enabling biased allosteric modulation remain unclear. Here we identify a helix 8-proximate allosteric site in the immune-metabolic receptor GPR84 and define how it achieves Gi -biased signalling. Cryo-EM structures of the GPR84-Gi complexes bound to the orthosteric agonist OX04539 alone or in combination with the positive allosteric modulator (PAM) PSB-16671 reveal that PSB-16671 binds at the interface of TM1, TM7, and helix 8, a location distinct from previously characterized GPCR allosteric pockets. Molecular dynamics simulations and mutagenesis uncover a polar interaction network linking orthosteric and allosteric sites through conserved residues including Asp662.50, Asn1043.36, and Asn3627.45. Unexpectedly, disrupting this network enhances allosteric cooperativity, indicating that conformational flexibility within the network is essential for allosteric communication. PSB-16671 stabilizes a receptor conformation with pronounced TM6 displacement that favours Gi coupling while disfavouring {beta}-arrestin recruitment. This Gi-biased profile sustains macrophage phagocytosis of cancer cells without the desensitization induced by balanced agonists. Sequence analysis suggests that helix 8-proximate allosteric sites may be broadly targetable across class A GPCRs, while receptor-specific contacts enable selective modulation. These findings establish structural and mechanistic principles for biased allosteric modulation applicable beyond GPR84.

biochemistry↗

In-situ Target Base Editing Combining with Biosensor-driven Strategy Reveals Critical Single Nucleotide Variants for Enhanced Recombinant Protein Secretion in Pichia pastoris

The disparity between the production and demand of recombinant proteins (r-proteins) has significantly hindered their commercial viability. Leveraging genomic resources offers substantial promise in enhancing our comprehension of metabolic and regulatory networks, thus facilitating the development of highly productive protein cell factories. However, the considerable gap between high-throughput strategies for monitoring r-protein secretion and genome perturbation in P. pastoris continues to obstruct the systematic linkage of genotype and phenotype, thereby limiting the optimization of production. Here, we developed a novel strategy combining dual-base editor-mediated in-situ genome engineering with nanobody-regulated biosensor-assisted droplet sorting to enhance r-protein secretion (BINDER) in P. pastoris. We successfully employed BINDER to screen recombinant human serum albumin (rHSA) hyper-producers and identified two critical SNVs conferring up to a 1.78-fold improved secretion titer from 113,632 mutants, providing valuable insights into the secretion mechanism. Fed-batch cultivation of the engineered strain resulted in the highest reported rHSA titer, 23.43g/L, in P. pastoris, demonstrating its substantial potential for industrial applications. Given the high transferability of base editors and the novel biosensors independence from the properties of the target protein, the strategy developed here might be expanded to a variety of microbial species and r-proteins.

synthetic biology↗

Continental-scale multi-omics reveals a distinct microbial-viral biome in sandy beach ecosystems structured by tidal zonation

Sandy beaches are dynamic coastal interfaces shaped by strong physical forcing and intense exchange between marine and terrestrial environments, yet their microbiomes remain poorly resolved at the genomic scale. Here we present a genome-resolved survey of microbial and viral communities across sandy beaches spanning a continental-scale latitudinal gradient along the Chinese coastline. By integrating cross-shore sampling, coastal geochemistry and large-scale multi-omics, we generated 978 metagenomes, 63 viromes and 72 metatranscriptomes, reconstructing 13,337 metagenome-assembled genomes and 38,255 viral populations. Sandy beach microbiomes exhibit exceptionally high genomic novelty, with more than 90% of species-level genomes representing previously undescribed taxa, suggesting that permeable coastal sediments constitute a distinct microbial and viral reservoir. Tidal zonation emerged as a dominant ecological driver structuring microbial diversity, metabolic strategies and virus-host interactions across cross-shore gradients. Genome-resolved analyses revealed systematic metabolic shifts from oxic heterotrophy in supratidal sediments toward increasingly chemolithotrophic and autotrophic pathways toward the low-intertidal and subtidal zone. Sandy beach microbiomes further encode broad potential for hydrocarbon and plastic transformation, together with diverse biosynthetic and antibiotic resistance repertoires that may mediate microbial chemical interactions. Together, these findings identify sandy beaches as a previously under-recognized microbial-viral biome shaped by tidal forcing, providing insight into microbiome evolution and coastal ecosystem resilience under increasing anthropogenic pressure.

microbiology↗

UBL3 UBL domain exhibits distinct helix-centered dynamic control among ubiquitin-like proteins

Ubiquitin-like protein 3 (UBL3) is a post-translational modifier that sorts proteins into small extracellular vesicles and regulates the trafficking of disease-associated proteins such as -synuclein. The structural and dynamic features of the UBL domain that underlie these functions, however, remain poorly understood. Here we performed in silico structural dynamics analysis of the UBL3 UBL domain using an NMR structure ensemble combined with anisotropic network modeling (ANM) and perturbation response scanning (PRS). Principal component analysis and residue-wise fluctuation analysis consistently revealed high flexibility in the C-terminal region of UBL3. Comparative ANM analysis across 20 ubiquitin-like proteins (UBLs) further showed that C-terminal flexibility is a conserved yet variable property within the UBL family. PRS analysis demonstrated that residues forming the central -helix of the {beta}-grasp fold exert greater dynamic control over collective motions than {beta}-sheet residues. Notably, UBL3 displayed the highest helix/sheet PRS effectiveness ratio among all UBLs analyzed, highlighting the prominent dynamic contribution of helix residues in this domain. Together, these results provide a structural basis for understanding UBL3-dependent protein interactions and disease-related mechanisms, and suggest that helix-centered dynamic control in the UBL domain may represent a potential target for modulating UBL3 function.

bioinformatics↗

Enhancer hubs govern chromatin topology and Th17 identity

Between one and two million noncoding regulatory elements have been described across mammalian genomes, but determining their functional role remains a challenge. To address this gap, we measure the regulatory potential of open chromatin regions (OCRs) in five closely related mouse CD4+ T cell subsets with ATAC-STARR-seq, then map endogenous enhancer function and three-dimensional contacts in Th17 cells with pooled CRISPR-based noncoding screens and high-resolution Micro-C. Of all CD4+ T cell OCRs, approximately 25% demonstrate largely subset-shared regulatory activity, though we identify subset-restricted active elements distinguishable by their sequence features. In Th17 cells, we reveal a set of core regulatory OCRs essential for subset polarization at the Batf, Rorc(t) and Il17a/f loci, and confirm their requirement for cell identity in vivo. At these three loci, we resolve nested yet selective enhancer-to-enhancer and enhancer-to-promoter physical interactions that converge into multi-enhancer hubs. Importantly, these hubs contain many of the strongest functional elements. Perturbation of a single enhancer within the Batf locus selectively disrupts hub contacts and Batf expression in Th17 cells, recapitulating the genome-wide transcriptional and chromatin accessibility signatures of a germline knockout. Together, this work assigns regulatory activity to accessible chromatin across CD4+ T cell subsets and couples the function of a set of essential elements to selective three-dimensional contacts in Th17 cells.

genomics↗

Deep Learning Reveals Persistent Individual Signatures in Bat Echolocation Calls of the Greater Leaf-nosed Bat

Intraspecific variation is a prerequisite for natural selection and can manifest in various phenotypic traits, including vocal signals. However, classifying individuals based on their vocalizations, or acoustic individual identification (AIID), remains a significant challenge. This is particularly true for species that use rapidly varying echolocation calls for orientation. Here, we demonstrate that deep learning can overcome the limitation of traditional methods and reveal persistent individual signatures within bat echolocation calls. We recorded echolocation calls from 34 individuals of the greater leaf-nosed bat (Hipposideros armiger) under controlled laboratory conditions, with 19 individuals recorded repeatedly over three months. We show that a convolutional neural network (CNN) dramatically outperforms a traditional method, achieving an average identification accuracy of 84% for single calls and 91% for call sequences. In contrast, the traditional Discriminant Functional Analysis method achieved accuracies of only 39% and 47%, respectively. Through systematically altering the temporal structure of echolocation calls in input sequences, we found that temporal patterning enhances individual classification accuracy, suggesting it contributes to the encoding of individual-specific information. This study revealed that echolocation calls of H. armiger can contain stable, individual identity that were previously undetectable. Our findings highlight the potential of deep learning for non-invasive AIID and provide a methodological basis for future studies aiming to monitor animals in more dynamic environments.

zoology↗

Structured Pooling Improves Detection of Rare Regulatory Mutations in Population-Scale Reporter Assays

Identifying genetic variants in noncoding DNA that impact gene expression and thereby contribute to disease risk remains a difficult but important challenge in genomic medicine. Modern reporter assays such as STARR-seq and MPRA provide an efficient and effective means of testing, in very high throughput, millions of variants captured directly from patient genomes. While these assays have previously been scaled to whole genomes and, separately, to populations, we report findings from the first whole-genome population-scale STARR-seq experiment performed on 100 individuals. In order to achieve that scale we devised a novel experimental design that partitions samples into pools so as to increase allele frequencies within pools and thereby reduce expected dropout and increase signal-to-noise ratio in experimental readouts. We show that this design produces more accurate estimates of variant effect sizes, and we provide a Bayesian model for robust estimation of those effect sizes that also reports full posterior distributions for assessment of confidence in estimates. Together, these methodological innovations facilitate the detection of functional regulatory variants, particularly rare variants, with much higher accuracy and at greater scale than previously possible. We demonstrate the utility of this approach on the task of functional annotation of quantitative trait loci such as eQTLs and caQTLs, and show concordance with patterns of constraint in transcription factor binding profiles.

bioinformatics↗

MetaGEAR Explorer: Rapid interactive searches and cross-cohort analyses of microbiome gene associations in disease

Background: Investigating functional gut microbiome signals remains challenging due to the large scale and sparsity of gene-level metagenomic profiles and reproducibility of microbial gene associations across microbiome studies is limited. Further, interactive tools for phenotype-aware cross-study meta-analysis are currently lacking. Results: We developed MetaGEAR Explorer, a web platform for interactive and programmatic gene-centric analyses that enables users to rapidly search genes of interest across 33 million gene families from 24 metagenomic cohorts spanning inflammatory bowel disease (IBD), colorectal cancer (CRC), and healthy individuals. To demonstrate our platform's capabilities, we first used narG, a well-characterized nitrate reductase gene in Enterobacteriaceae (including Escherichia coli and Klebsiella species), to evaluate the detection of remotely related, disease-relevant homologs. While sequence-based searches using the E. coli narG gene as a query failed to capture the known diversity of narG, MetaGEAR Explorer's domain-based search expansion identified 160 NarG-like gene families with consistent IBD enrichment across cohorts. This included narG homologs from Veillonella parvula and Veillonella atypica that have been recently implicated in intestinal inflammation. We further applied MetaGEAR Explorer to investigate the underexplored diversity of clbS, the self-protection gene against the bacterial genotoxin colibactin, which is implicated in CRC tumorigenesis. The canonical clbS is part of the E. coli clb operon, which produces colibactin. Our analysis showed that E. coli-associated clbS was rare in healthy individuals but increased in disease (1.85% in Healthy, 6.21% in IBD, and 7.62% in CRC). In contrast, domain-based expansion revealed widespread clbS-domain (DUF1706) homologs, present in 95.15% of healthy individuals, while disease-associated contributors shift from commensal Clostridia to Gammaproteobacteria. Notably, Proteus mirabilis was identified as a novel potential ClbS-like carrier enriched in IBD. Furthermore, much of this prevalence was driven by a single unclassified gene family, present in 63.40% of healthy individuals. Conclusions: MetaGEAR Explorer facilitates rapid cross-cohort functional meta-analyses and can identify reproducible, biologically interpretable microbial gene signatures in IBD and CRC, such as newly identified sequence-domain dynamics in nitrate respiration and colibactin self-protection.

bioinformatics↗

A self-complementary recombinant adeno-associated virus vector coding for an anchorless prion protein carrying the G127V mutation extends survival in a rodent prion disease model

The replacement of a single codon in the human prion gene, causing the substitution of glycine with valine at position 127 (G127V) of the prion protein (PrP), prevents development of prion disease. We set out to explore if prion disease survival extension manifests in mice if the V127 mutant is delivered through a recombinant adeno-associated virus (rAAV) packaged as a self-complementary DNA. The notorious delivery limitations of rAAVs were overcome using a cross-correction approach that relied on the expression of the mutation in the context of glycosylphosphatidylinositoI-anchorless ({Delta}GPI) PrP. In this proof-of-concept study, we inoculated Rocky Mountain Laboratory (RML) prions into knock-in mice, in which the endogenous murine prion protein gene (Prnp) was replaced with the bank vole prion protein gene (BvPrnp). Prion-inoculated mice that were retro-orbitally transduced with a protective rAAV vector encoding BvPrnpV127{Delta}GPI survived [~]50 days longer than control mice that were unprotected. A deep proteomic analysis revealed that BvPrnpV127{Delta}GPI was protective by slowing perturbations to the proteome observed in late-stage RML prion disease. In addition to capturing details of synaptic decay and depletion of proteins in proximity to PrP, the proteomic dataset revealed the identity of proteins of potential diagnostic value that may be central to the brains attempt to fight prion disease by contributing to astrocytosis or microgliosis, by coping with calcium influx, or by enhancing the endoplasmic reticulum processing of essential proteins. Taken together, our results demonstrate that a gene therapy based on a GPI-anchorless PrP containing the G127V mutation can delay the onset of prion disease in mice, providing a framework for development of a corresponding therapy in humans. AUTHOR SUMMARYA rare change in the human prion protein, involving a single building block, has been linked to strong protection against prion diseases--fatal neurodegenerative disorders. This study tested whether that protective effect could be reproduced using gene therapy in mice. To this end, we exposed the animals to infectious prions and then delivered the protective version of the protein into mice using a viral carrier. Treated mice survived about seven weeks longer than untreated animals, showing that the approach can meaningfully slow disease progression. To understand why, we examined changes in brain proteins during disease and found that treatment helped preserve the normal protein levels of cellular proteins, particularly those involved in communication between nerve cells. The analysis also identified proteins altered in the disease that are linked to the brains defense responses, including inflammation, stress handling, and protein processing, some of which may serve as future disease markers. Importantly, the limited protection observed was not due to poor delivery of the therapy but likely reflects biological limits of the model used. Overall, the findings support the idea that gene therapies based on naturally protective human variants could help slow prion diseases and improve understanding of how the brain responds to them.

neuroscience↗

Distributed elasticity: a high-reward, moderate-risk strategy for efficient control modulation in insect flight

The environments inhabited by flying insects demand a balance between flight efficiency and flight manoeuvrability. In structural oscillators such as the insect indirect flight motor, efficiency (arising from resonance) and manoeuvrability (arising from kinematic modulation) are typically quid pro quo, with modulation incurring penalties to efficiency. Band-type resonance is a phenomenon that offers, in theory, a strategy to lessen these penalties via careful navigation through a band of efficient kinematic states. However, identifying this band is challenging: no methods exist to identify the complete band in realistic motor models, involving elasticity distributed across thorax and wing. Nor are the effects of elasticity distribution on the band known. In this work, we address both open topics. We present a suite of numerical methods for identifying the complete resonance band in general systems. Applying them to models of the insect flight motor with distributed elasticity--thoracic and wing flexion--reveals that distributed elasticity is moderate-risk but high-reward morphological feature. Well-tuned distributions expand the resonance band over fourfold whereas poorly-tuned distributions completely extinguish the resonance band. These results indicate that distributing elasticity across the insect flight motor can have adaptive value, and motivate broader work identifying distributions across species.

systems biology↗

Mechanism of phospholipid transport to the bacterial outer membrane by TAM.

Gram-negative bacteria transport phospholipids from the inner membrane (IM) to the outer membrane (OM) via poorly understood processes. These processes are essential for cell growth and the establishment of an antibiotic-resistant barrier. Here, we conducted single-particle cryo-electron microscopy, in vivo functional assays, and lipidomics to investigate the role of the "translocation and assembly module" (TAM) in lipid transport. We found that the OM-embedded subunit TamA anchors the IM-embedded bridge-like subunit TamB to the OM by forming a functional stable hybrid-barrel structure with the highly conserved C-terminal domain of unknown function 490 (DUF490). Using in vivo disulfide-tethering experiments we found that a highly conserved amphipathic helix within TamB DUF490 is important for TAM to function in OM maintenance. We also found that TamB DUF490 forms a {beta}-taco channel containing lipid-like densities and that the lipophilic property of the channel is important for TAM to maintain the levels of cardiolipin in the OM. Not only do our data support a novel model in which TAM acts to direct specific lipid classes into the OM, but it also supports the notion that TamB is a bacterial evolutionary prototype of a structurally homologous superfamily of eukaryotic bridge-like lipid transfer proteins.

biochemistry↗

PARG inhibition sequesters nuclear PAR-binding proteins, including XRCC1 and its partners, into nuclear condensates to elicit cytotoxicity

DNA breaks activate PARP1/2 to synthesize poly(ADP-ribose) (PAR), which relaxes chromatin and recruits DNA repair factors. Normally, PAR is short-lived, rapidly degraded by poly(ADP-ribose) glycohydrolase (PARG). While PARP1/2 inhibitors are established therapies for homologous recombination (HR)-deficient cancers, predictive biomarkers for PARG inhibition (PARGi) remain undefined. Using parallel genome-wide CRISPR screens with PARP and PARG inhibitors, we show that PARGi is synthetically lethal with loss of several PAR-binding factors, including XRCC1-LIG3, POLB, ALC1/CHD1L, ARH3, and PARG itself, but notably not with HR deficiency. Conversely, loss of PARP1, NMNAT1 (required for nuclear NAD synthesis), or UNG (upstream of APE1 cleavage and PARP1 activation), confers PARGi resistance. Mechanistically, PARGi induces time- and dose-dependent formation of PARP1-and PAR-dependent nuclear condensates containing XRCC1 and associated repair factors in otherwise undamaged cells. These condensates do not harbor active DNA breaks but instead sequester PAR-binding repair proteins, depleting their available nuclear pool and impairing their recruitment to genuine DNA breaks. While our analysis focused on XRCC1, PARG inhibition likely sequesters additional PAR- and PARP1-binding proteins. Thus, we propose that PARGi sequesters PAR-binding proteins to elicit toxicity, explaining the essentiality of PARG (but not PARP1) and identifying the loss of PAR-binding factors as candidate predictive biomarkers for PARG-targeted therapy.

molecular biology↗

Recombination rate and efficiency of linked selection in small and large stickleback populations

Population genetic theory predicts that natural selection will be more efficient in large than small populations because genetic drift reduces the efficiency of selection in small populations. Small populations adapting to new environments can also be expected to evolve higher recombination rates to facilitate adaptation as well as to dissociate and purge harmful mutations. We tested these hypotheses (1) by investigating differences in the strength of association between nucleotide diversity ({pi}) and recombination rate across the genomes of nine-spined sticklebacks (Pungitius pungitius) from four small freshwater (mean Ne {approx} 2 578) and four large marine (mean Ne = 86 742) populations, as well as (2) by comparing recombination rates between small and large populations using population specific linkage maps. We found the predicted positive correlation of{pi} with recombination rate from all but the smallest freshwater populations, suggesting prevalent linked selection even after accounting for variation in GC/CpG content, and gene density. Mean recombination rates did not differ between freshwater and marine populations, except that the smallest Ne freshwater population exhibited significantly elevated recombination rate. GWAS analyses suggested a polygenic basis for recombination rates. These results suggest an important role for linked selection in reducing{pi} in low recombination regions especially in large populations. Moreover, as predicted by theory, at least one of the small freshwater populations appears to have evolved a higher recombination rate than its marine ancestors.

evolutionary biology↗

Functional impact of PCSK9 variants on LDL uptake in a knockout hepatic model

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a central regulator of low-density lipoprotein (LDL) cholesterol metabolism, yet the functional consequences of many clinically observed PCSK9 variants remain unknown. To establish a rigorous system for quantitative variant assessment, we generated a PCSK9 knockout (KO) HepG2 cell line through CRISPR/Cas9-mediated deletion of exons 2-8, effectively removing both the prodomain and catalytic regions required for PCSK9 function. This null background enabled systematic functional mapping of wild-type (WT) PCSK9 and multiple clinically relevant variants representing well-characterized, recurrent, and previously understudied alleles. Functional assays revealed pronounced heterogeneity among variant activities. The classical gain-of-function (GOF) variants D374Y and R496W exhibited robust suppression of LDL uptake, whereas A443T--an infrequently reported and previously uncharacterized variant--demonstrated a loss-of-function (LOF)-like phenotype with significantly enhanced LDL uptake. Additional poorly characterized variants, including V4I, R104C/V114A, and R496W/N425S, displayed minimal functional profiles, providing novel mechanistic insights. Surface LDL receptor (LDLR) levels generally correlated with LDL uptake but revealed unique patterns for specific variants. This KO-based rescue system provides a high-resolution framework for mechanistic classification of both established and poorly characterized PCSK9 variants, bridging the gap between genetic discovery and functional interpretation while supporting precision lipid-lowering strategies.

biochemistry↗

Automated Cyclic Super-Resolution Microscopy for Nanoscale Protein Mapping

Nanoscale mapping of multiple molecular targets is essential for decoding cellular architecture, but current approaches are limited by low throughput, intensive manual intervention, and signal variability across imaging cycles. Here, we introduce CycSTORM, an integrated super-resolution imaging platform for automated cyclic (d)STORM that enables multiplexed nanoscale protein mapping in single cells. To overcome the instability inherent in multi-day imaging, CycSTORM combines automated fluidic exchange, active 3D drift correction, and an oxygen-excluded imaging environment to stabilize fluorophore blinking and enables sub-5 nm registration across day-long experiments. Furthermore, CycSTORM incorporates a rapid chemical inactivation step using meta-chloroperoxybenzoic acid (mCPBA), eliminating >99.9% residual fluorescence within 10 minutes and minimizing inter-cycle crosstalk while preserving sample integrity. By standardizing labeling to Alexa Fluor 647, a fluorophore with stable and well-characterized blinking behavior, CycSTORM minimizes fluorophore-dependent variation and provides a robust platform for consistent localization precision across cycles, enabling reliable mapping of protein organization in single cells. Using CycSTORM, we simultaneously map multiple protein targets within the same cells with nanometer precision. Together, these advances transform cyclic super-resolution imaging into a scalable approach for quantitative nanoscale mapping of molecular organization in single cells.

cell biology↗

Identification of the Phytophthora PAMP Pep-13 Receptor Using Diploid Potato Inbred Lines

Plants employ cell surface receptors to recognize pathogen-associated molecular patterns (PAMPs) and activate pattern-triggered immunity, a crucial defense mechanism against invading pathogens. Pep-13 is a PAMP derived from a class of conserved cell wall transglutaminases present in Phytophthora species, and its receptor PERU (Pep-13 receptor unit), was reported recently. In our parallel study, we observed distinct responses to Pep-13 between two diploid potato inbred lines: E4-63 recognizes Pep-13, whereas A6-10 does not. Genetic analysis demonstrated that Pep-13 recognition in E4-63 is controlled by a single genetic locus, tentatively designated TGER (Transglutaminase elicitor response). Through bulked segregant analysis sequencing, followed by complementation assays, we found that the TGERa gene in E4-63 is essential for Pep-13 recognition. Sequence alignment revealed that TGERa shares 99.91% amino acid sequence identity with PERU, indicating that TGERa and PERU are allelic variants of the same gene (PERU/TGERa). TGERb, a highly homologous gene of TGERa, was identified in the E4-63 genome; notably, TGERa, but not TGERb, can recognize Pep-13. We further demonstrated that TGERb exhibits defects in ligand binding. Additionally, we found that the TGERa allele in A6-10 is a weak allele with reduced expression levels, presumably resulting from a 3 kb DNA fragment insertion in its first intron. Heterologous introduction of TGERa into Nicotiana benthamiana and tomato significantly enhanced their resistance to Phytophthora infestans. Collectively, our findings confirm that PERU/TGERa functions as the Pep-13 receptor in potato and provide a valuable molecular target for improving Phytophthora resistance in plants.

plant biology↗

Red yeast rice-derived MKA ameliorates cardiac hypertrophy in hypertensive rats by inhibiting ERK1/2/c-Fos pathway

BackgroundCardiac hypertrophy is a key pathological process in hypertensive heart failure, yet current antihypertensive therapies do not directly target it. Red yeast rice (RYR), rich in monacolin K {beta}-hydroxy acid (MKA), is known for lipid-lowering effects, but its potential to ameliorate cardiac hypertrophy is unreported. PurposeTo investigate the effects of RYR-derived MKA on cardiac hypertrophy in spontaneously hypertensive rats (SHR) and elucidate its molecular mechanisms. MethodsSpontaneously hypertensive rats (SHR) were treated with 0.6% red yeast rice for 8 weeks to assess its effects on blood pressure, cardiac function (echocardiography), cardiac hypertrophy and fibrosis (histopathology), and multi-organ toxicity (histopathology). A multigenerational study was conducted to evaluate protective effects in offspring. Network pharmacology and transcriptomic analysis were integrated to predict molecular targets, which were subsequently validated by molecular docking and experiments. ResultsEight-week RYR treatment significantly reduced blood pressure, inhibited cardiac hypertrophy and fibrosis, and improved cardiac function without gender differences. No pulmonary, hepatic, or renal toxicity was observed. Offspring from treated parents exhibited further reduced hypertrophy upon continued treatment. Mechanistically, MKA bound ERK1/2 with high affinity, inhibiting its phosphorylation and downstream c-Fos expression, thereby downregulating hypertrophy markers. ConclusionRed yeast rice improves hypertensive cardiac hypertrophy via MKA-mediated inhibition of the ERK1/2/c-Fos pathway. Its multi-organ safety and transgenerational effects offer a novel dual-therapy strategy for hypertension and cardiac hypertrophy. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=139 HEIGHT=200 SRC="FIGDIR/small/710945v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@8225acorg.highwire.dtl.DTLVardef@775f43org.highwire.dtl.DTLVardef@10f5201org.highwire.dtl.DTLVardef@d0cd88_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗