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Che, J.

Publications and source records attributed to Che, J..

15 recordsLinked to original sources

Shared phylogeographic structuring and recurrent hybridization underlie the diversification of Microhyla frog complexes in the Indochinese biodiversity hotspot

Comparative phylogeography provides a powerful framework to identify the historical processes shaping biodiversity hotspots by testing whether co-distributed species exhibit shared patterns of diversification. Southeast Asia harbors exceptional biodiversity, yet the extent to which common paleogeographic and climatic drivers have structured diversification across taxa remains poorly understood. Here, we investigated the evolutionary history of five widespread Microhyla species complexes distributed across the Indochinese Peninsula and adjacent regions using dense mitochondrial sampling (1,388 individuals) combined with genome-scale ddRAD sequencing (280 individuals). Across all complexes, both approaches recovered multiple lineages and remarkably congruent phylogeographic breaks and contact/intergradation zones associated with major Indochinese regions, including Myanmar, the Tenasserim-Malay Peninsula, southern Vietnam, and northern Vietnam-southern China, supporting the hypothesis that Indochina functions as a mosaic of stable biogeographic units. However, lineage divergence varied substantially among complexes, suggesting that common biogeographic drivers interacted with species-specific demographic histories. Phylogenomic analyses and cyto-nuclear discordance further revealed historical introgression in every complex, indicating that diversification involved both long-term allopatric isolation and reticulate evolution. These findings portray the Indochinese biodiversity hotspot as a dynamic evolutionary system where cycles of fragmentation and reconnection have repeatedly reshaped lineage boundaries. Moreover, the complex phylogeographic structure recovered exemplifies the urgent need for taxonomic revisions, for which genome-scale data provide an essential framework to validate mitochondrial hypotheses and assess admixture patterns for species delimitation. Finally, regions such as the southern Annamites and Tenasserim Hills emerged as recurrent hotspots of genetic diversity across independent lineages, highlighting their importance for conserving not only species/lineage richness but also the evolutionary processes and adaptive potential that sustain biodiversity.

zoology↗

Covalent remodeling of CRBN creates a non-canonical neosubstrate interface with NTAQ1

Molecular glue degrader EM12-FS covalently modifies cereblon (CRBN) His353, enabling selective recruitment of the neosubstrate NTAQ1 to the CRL4CRBN ubiquitin ligase. We determined the cryo-EM structure of the NTAQ1-EM12-FS-CRBN-DDB1 complex, revealing a non-canonical neosubstrate interface created by covalent remodeling of the CRBN sensor loop. Imidazylation repositions His353 to eliminate the steric clash that prevents NTAQ1 engagement by reversible IMiDs, and the engineered interface is stabilized by a distinctive T-shaped C-H/{pi} interaction between sulfated His353 and NTAQ1 Phe126. Biochemical and mutational analyses define the determinants of ternary complex formation and ubiquitination. These findings show that site-specific synthetic modification of CRBN can reprogram induced-proximity pharmacology, expanding specificity beyond the G-loop degron and establishing a framework for covalent engineering of new degrader modalities.

biochemistry↗

A druggable redox switch on SHP1 controls macrophage inflammation

Immunological proteins are major disease targets, yet most remain undrugged. Post-translational redox modification of cysteine residues has emerged as an important mode of immune cell regulation, particularly in macrophage cytokine responses. Here, we develop a strategy for systematic discovery and small-molecule functionalization of redox-regulated cysteines on immunological proteins. Using deep redox proteomics, we annotate 788 in vivo redox-regulated cysteines across diverse immune-relevant protein domains. We demonstrate how these sites enable cysteine-directed pharmacology through discovery of a novel cysteine activation site on the immune regulator SHP1. Targeting Cys102, we develop a highly selective covalent agonist, SCA, which binds the N-SH2 domain to relieve autoinhibition and activate SHP1. In mouse and human macrophages, SCA selectively engages SHP1 Cys102, antagonizing IRAK signaling and LPS-induced pro-inflammatory cytokine production. Together, this work identifies a druggable cysteine redox switch controlling macrophage cytokine responses and provides a compendium of redox-regulated sites for therapeutic development.

biochemistry↗

Overcoming EGFR resistance by monovalent and bident inhibitors targeting Cys775

Covalent targeting of EGFR cysteine 797 by osimertinib is one of the most successful breakthroughs in targeted therapy, fundamentally transforming the treatment landscape for non-small cell lung cancer (NSCLC) patients. However, resistance driven by mutation of C797 remains a major clinical challenge. Developing novel covalent strategies beyond C797 targeting presents a compelling opportunity for next-generation EGFR inhibitors. We first demonstrated that cysteine 775, located deep within the ATP-binding pocket, is accessible by a rationally designed covalent molecule ZNL-3, which as the first-in-class covalent cysteine 775 inhibitor exhibited strong efficacy in osimertinib-resistant mouse models. To further enhance resilience to resistance-causing mutations, we developed a dual-warhead, bident compound--YNW-1--which covalently targets both cysteine 775 and 797 simultaneously. YNW-1 is the first intramolecular lock to exhibit balanced reactive efficiency on both cysteines, rendering single-site mutations ineffective to confer resistance. The discovery of ZNL-3 and YNW-1 represents significant advancements in EGFR-targeted drug development, and further optimization toward clinical translation is a worthwhile strategy. SIGNIFICANCE: This study establishes the therapeutic potential of an EGFR covalent inhibitor through unprecedented targeting of cysteine 775 and provides the first demonstration that dual cysteine engagement offers superior efficacy over conventional covalent inhibitors by delaying resistance.

cancer biology↗

Positive Selection Screen for Natural Product β-Catenin Inactivators

Many genetically validated targets in cancer, including the transcription factor {beta}-catenin ({beta}-cat), have historically been viewed as undruggable. Cell-based phenotypic screening of chemical compounds can reveal new biological and pharmacological principles. Natural products are powerful probes because of their superior structural diversity, drug-like properties, and biological activities as compared to unoptimized synthetic compounds. We screened 326,304 natural product mixtures (40,744 extracts and 285,560 fractions derived from them) using mammalian cells expressing an oncogenic version of {beta}-cat fused to a suicide protein. Multiple fractions degraded the {beta}-cat fusion protein or drove it into a compartment where both fusion partners were apparently inactive. The active natural product from one of the latter specifically activates novel, but not classical, protein kinase Cs (PKCs) and thereby relocates {beta}-cat to juxtamembrane vacuolar structures. These findings suggest a path for inactivating oncogenic {beta}-cat and underscore the power of screening natural product collections with robust phenotypic assays.

cancer biology↗

SARS-CoV-2 NSP14 inhibitor exhibits potent antiviral activity and reverses NSP14-driven host modulation

The emergence of SARS-CoV-2 variants and drug-resistant mutants highlights the urgent need for novel antiviral therapeutics. SARS-CoV-2 NSP14, an N7-guanosine methyltransferase, plays a critical role in viral RNA capping, enabling viral replication and immune evasion. While NSP14 has emerged as a promising drug target, its role in host-virus crosstalk and the cellular consequences of NSP14 inhibition remain poorly understood. Here, we present the identification and characterization of C10, a highly potent and selective first-in-class non-nucleoside inhibitor of the NSP14 S-adenosylmethionine (SAM)-binding pocket. C10 demonstrates robust antiviral activity against SARS-CoV-2, including its variants, with EC50 values ranging from 64.03 to 301.9 nM, comparable to the FDA-approved drug remdesivir in our cell-based assays. C10 also exhibits broad-spectrum activity against other betacoronaviruses and inhibits SARS-CoV-2 at the replication stage. C10 suppresses viral translation and exhibits immunostimulatory effect. Additionally, C10 specifically reversed NSP14-mediated alterations in host transcriptome. The antiviral efficacy of C10 was further validated in a transgenic mouse model of SARS-CoV-2 infection. Our findings highlight C10 as a promising candidate for the development of effective treatments against SARS-CoV-2 and its emerging variants. This study also uncovers a novel mechanism of NSP14 in SARS-CoV-2 pathogenesis and its therapeutic potential, providing insights that may extend to other viral capping methyltransferases.

microbiology↗

Stromal cells modulate innate immune cell phenotype and function in colorectal cancer via the Sialic acid/Siglec axis

BackgroundThe immunosuppressive tumour microenvironment (TME) reduces immune response effectiveness in stromal-rich tumours, including CMS4 colorectal cancer (CRC). Mesenchymal stromal cells (MSCs), precursors to cancer-associated fibroblasts (CAFs), promote cancer progression by suppressing anti-tumour immune responses. Hypersialylation of glycans on tumours engages Siglec receptors on immune cells, driving immune dysfunction, but its role in stromal-mediated immunosuppression remains unclear. MethodsSialic acids and Siglec ligands were measured on CRC tissue, primary human CAFs, and tumour-conditioned-mesenchymal stromal cells (MSCTCS) and CAF using immunohistochemistry and flow cytometry. The effect of stromal cell sialylation on macrophages and NK cells was assessed in ex vivo primary stromal and immune cell co-cultures and expression of Siglec-10 and immune cell phenotype markers and function were measured by flow cytometry. Using an immunocompetent Balb/c CT26 mouse model, we induced tumours with/without conditioned stromal cells, with/without pre-treatment of stromal cells with sialyltransferase inhibitor (3FAX) or sialidase (E610). We assessed the effect of stromal cell sialylation on macrophages and NK cells in the tumour and secondary lymphoid tissues by flow cytometry. ResultsStromal cells, including CAFs, in CRC tumours are highly sialylated compared to epithelial cancer cells and are associated with high expression of ST6GalNAC6. Genetic knockdown of ST6GalNAC6 reduced the expression of stromal cell Siglec-10 ligands in MSCs. CAFs and MSCTCS induced Siglec-10 on macrophages and NK cells and impaired NK cell cytotoxicity. Sialidase treatment reduced Siglec-10 expression, restoring NK cell function. In vivo, desialylation of stromal cells increased macrophage activation (CD11b+CD80+) and reduced immunosuppressive marker expression (CD206, PD-L1, Siglec-G) in lymphoid tissues, indicating sustained systemic anti-tumour immunity. Intratumoural NK cells exhibited high Siglec-G expression and impaired cytotoxicity, and granzyme B expression significantly increased with sialidase treatment of stromal cells. In an inflammatory tumour model, inflammatory tumour-conditioned (iTCS) MSCs promoted metastasis and Siglec-G induction on NK cells and macrophages, both reversed by sialyltransferase inhibition, underscoring the effects of stromal modulation of innate immune cell function in inflammatory tumours. ConclusionStromal cell sialylation modulates innate immune suppression in CRC via the sialic acid/Siglec axis. Targeting stromal sialylation restores NK cytotoxicity and macrophage activation, offering a novel therapeutic strategy for immunosuppressive stromal-rich tumours. What is already known on this topicO_LIThe tumour microenvironment of consensus molecular subtype 4 (CMS4) colorectal cancer (CRC) is associated with high stromal burden, poor immune infiltration, poor response to anti-cancer therapies and thus poor patient prognosis. Immune checkpoint inhibitors (ICIs) have limited impact on stromal-rich CRC tumours, therefore highlighting the need to discover and target novel mechanisms of tumour immune evasion. C_LIO_LIEmerging studies have highlighted that stromal cells in CRC and pancreatic ductal adenocarcinoma (PDAC) are highly sialylated, expressing even higher levels of sialic acid on their cell surface than epithelial cancer cells. Targeting stromal cell sialylation has unveiled promising data in restoring the anti-tumour activity of T cells and macrophages. There is a need to explore the effects of targeting stromal cell sialylation on other immune cells of the TME and to evaluate the Siglec/sialic acid axis of stromal and immune cells in resistant CRC tumours. C_LI What this study addsO_LIWe reveal ST6GalNAC6 as a sialyltransferase enzyme that regulates the production of Siglec-10 ligands in CRC stromal cells. Overexpression of ST6GalNAC6 and Siglec-10 correlated with poor survival in CRC and mesenchymal CRC tumours. C_LIO_LIWe show for the first time an induction of Siglec-10 expression on macrophages and NK cells in stromal-immune co-culture experimental models with hypersialylated MSCs and CAFs in vitro and ex vivo. Targeting stromal cell sialylation increased NK cell cytotoxicity of CRC cells, indicating a direct functional role for stromal cell sialylation in immunosuppression. C_LIO_LIAn immunogenic mouse model of CRC was used to evaluate the potential therapeutic efficacy of targeting stromal cell sialylation in overcoming stromal cell-mediated immunosuppression in CRC. Sialic acid-targeting of stroma slowed tumour growth and reduced inflammation-driven metastasis. This was associated with greater infiltration and activation of macrophages and NK cells with stromal cell sialic acid depletion, highlighting stromal cell sialylation as a mechanism of innate immune cell suppression in stromal-rich CRC. C_LI How this study might affect Research, Practice or PolicyO_LIOur research provides insight into a novel mechanism of stromal cell-mediated immunosuppression of innate immune cells in CRC and may open up new avenues of research for targeting stromal cells in stromal-rich TMEs such as pancreatic, breast and ovarian cancers. C_LIO_LIOur research identifies a stromal cell effect of enhancing Siglec expression on tumour infiltrating innate immune cells as a novel immune checkpoint, which may be useful in identifying potential novel immunotherapeutic combinations in future. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=151 SRC="FIGDIR/small/642985v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@cbafc3org.highwire.dtl.DTLVardef@80474forg.highwire.dtl.DTLVardef@1c9d050org.highwire.dtl.DTLVardef@8b6551_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Small-molecule allosteric activator of ubiquitin-specific protease 7 (USP7)

Ubiquitin-specific protease 7 (USP7) is a deubiquitylase essential for cell homeostasis, DNA repair, and regulation of both tumor suppressors and oncogenes. Inactivating USP7 mutations have been associated with Hao-Fountain Syndrome (HAFOUS), a rare neurodevelopmental disorder. Although a range of USP7 inhibitors have been developed over the last decade, in the context of HAFOUS as well as oncogene regulation, USP7 activators may represent a more relevant approach. To address this challenge, we report the discovery and characterization of a small-molecule activator of USP7 called MS-8. We showed that MS-8 activates USP7 by engaging the allosteric C-terminal binding pocket of USP7, thus mimicking the allosteric autoactivation by the USP7 C-terminal tail. We observed that MS-8 engages and activates mutant USP7 in a cellular context, impacting downstream proteins. Taken together, our study provides validation of the USP7 activator that paves the way towards novel activation-driven USP7 pharmacology.

biochemistry↗

The Amphibian Genomics Consortium: advancing genomic and genetic resources for amphibian research and conservation

Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomic resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomic resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, anti-predator strategies, and resilience and adaptive responses. They also serve as essential models for studying broad genomic traits, such as evolutionary genome expansions and contractions, as they exhibit the widest range of genome sizes among all animal taxa and possess multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The emergence of long-read sequencing technologies, combined with advanced molecular and computational techniques that improve scaffolding and reduce computational workloads, is now making it possible to address some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC, https://mvs.unimelb.edu.au/amphibian-genomics-consortium) in early 2023. This burgeoning community already has more than 282 members from 41 countries. The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and call on the research and conservation communities to unite as part of the AGC to enable amphibian genomics research to "leap" to the next level.

genomics↗

Discovery of Potent Degraders of the Dengue Virus Envelope Protein

Targeted protein degradation has been widely adopted as a new approach to eliminate both established and previously recalcitrant therapeutic targets. Here we report the development of small molecule degraders of the envelope (E) protein of dengue virus. We developed two classes of bivalent E-degraders, linking two previously reported E-binding small molecules, GNF-2 and CVM-2-12-2, to a glutarimide-based recruiter of the CRL4CRBN ligase to effect proteosome-mediated degradation of the E protein. ZXH-2-107 (based on GNF-2) is an E degrader with ABL inhibition while ZXH-8-004 (based on CVM-2-12-2) is a selective and potent E-degrader. These two compounds provide proof-of-concept that difficult-to-drug targets such as a viral envelope protein can be effectively eliminated using a bivalent degrader and provide starting points for the future development of a new class antiviral drugs.

biochemistry↗

Single-cell dissection of prognostic architecture and immunotherapy response in Helicobacter pylori infection associated gastric cancer

Most of the gastric cancer (GC) worldwide are ascribed to Helicobacter pylori (H. pylori) infections, which have a detrimental effect on the immunotherapys efficacy. Comprehensively dissecting the key cell players and molecular pathways associated with cancer immunotherapies is critical for developing novel therapeutic strategies against H. pylori infection associated GC. We performed a comprehensive single-cell transcriptome analysis of nine GC with current H. pylori infection (HpGC), three GC with previous H. pylori infection (ex-HpGC), six GC without H. pylori infection (non-HpGC), and six healthy controls (HC). We also investigated key cell players and molecular pathways associated with GC immunotherapy outcomes. We revealed the molecular heterogeneity of different cell components in GC including epithelium, immune cells, and cancer-associated fibroblasts (CAFs) at the single-cell level. The malignant epithelium of HpGC exhibited high expression level of inflammatory and epithelial-mesenchymal transition (EMT) signature, HpGC and ex-HpGC were enriched with VEGFA+ angiogenic tumor-associated macrophages (Angio-TAM) and IL11+ inflammatory CAF (iCAF), characterized by high expression levels of NECTIN2 and VEGFA/B. Additionally, we found significant correlations between the abundance of iCAF with Angio-TAM and TIGIT+ suppressive T cells, and iCAF interacted with Angio-TAM through the VEGF and ANGPTL angiogenic pathways. We also developed an immune signature and angiogenic signature and demonstrated that the iCAF abundance and angiogenic signature could predict poor immunotherapy outcomes in GC. We revealed the transcriptome characteristics and heterogeneity of various cellular constituents of HpGC and demonstrated that a synergistic combination of immunotherapy and anti-angiogenic targeted therapy may be an effective therapeutic modality for HpGC.

cancer biology↗

A comprehensive landscape of the zinc-regulated human proteome

Zinc is an essential micronutrient that regulates a wide range of physiological processes, principally through Zn2+ binding to protein cysteine residues. Despite being critical for modulation of protein function, for the vast majority of the human proteome the cysteine sites subject to regulation by Zn2+ binding remain undefined. Here we develop ZnCPT, a comprehensive and quantitative mapping of the zinc-regulated cysteine proteome. We define 4807 zinc-regulated protein cysteines, uncovering protein families across major domains of biology that are subject to either constitutive or inducible modification by zinc. ZnCPT enables systematic discovery of zinc-regulated structural, enzymatic, and allosteric functional domains. On this basis, we identify 52 cancer genetic dependencies subject to zinc regulation, and nominate malignancies sensitive to zinc-induced cytotoxicity. In doing so, we discover a mechanism of zinc regulation over Glutathione Reductase (GSR) that drives cell death in GSR-dependent lung cancers. We provide ZnCPT as a resource for understanding mechanisms of zinc regulation over protein function.

cell biology↗

Covalent Disruptor of YAP-TEAD Association Suppresses Defective Hippo Signaling

The transcription factor TEAD, together with its coactivator YAP/TAZ, is a key transcriptional modulator of the Hippo pathway. Activation of TEAD transcription by YAP has been implicated in a number of malignancies, and this complex represents a promising target for drug discovery. However, both YAP and its extensive binding interfaces to TEAD have been difficult to address using small molecules, mainly due to a lack of druggable pockets. TEAD is post-translationally modified by palmitoylation that targets a conserved cysteine at a central pocket, which provides an opportunity to develop cysteine-directed covalent small molecules for TEAD inhibition. Here, we employed covalent fragment screening approach followed by structure-based design to develop an irreversible TEAD inhibitor MYF-03-69. Using a range of in vitro and cell-based assays we demonstrated that through a covalent binding with TEAD palmitate pocket, MYF-03-69 disrupts YAP-TEAD association, suppresses TEAD transcriptional activity and inhibits cell growth of Hippo signaling defective malignant pleural mesothelioma (MPM). Further, a cell viability screening with a panel of 903 cancer cell lines indicated a high correlation between TEAD-YAP dependency and the sensitivity to MYF-03-69. Transcription profiling identified the upregulation of proapoptotic BMF gene in cancer cells that are sensitive to TEAD inhibition. Further optimization of MYF-03-69 led to an in vivo compatible compound MYF-03-176, which shows strong antitumor efficacy in MPM mouse xenograft model via oral administration. Taken together, we disclosed a story of the development of covalent TEAD inhibitors and its high therapeutic potential for clinic treatment for the cancers that are driven by TEAD-YAP alteration.

cancer biology↗

Ribosome profiling reveals the translational landscape and allele-specific translation efficiency in rice

Translational regulation is a critical step in the process of gene expression and governs the synthesis of proteins from mRNAs. Many studies have revealed the translational regulation in plants in response to various environmental stimuli. However, there has been no comprehensive landscape of translational regulation and allele-specific translation efficiency in multiple tissues of plants, especially in rice, a main staple crop feeding nearly half of the world population. Here, we used RNA-seq and Ribo-seq data to analyze the transcriptome and translatome of an elite hybrid rice SY63 and its parental varieties ZS97 and MH63. The results revealed that gene expression patterns varied more significantly between tissues than between varieties at both transcriptional and translational levels. Besides, we identified 3,392 upstream open reading frames (uORFs), and most of the uORF-containing genes were enriched for transcription factors. Only 668 long non-coding RNAs could be translated into peptides. Finally, we discovered numerous genes with allele-specific translation efficiency in SY63, and further demonstrated that some cis-regulatory elements (secondary structures of mRNAs and the binding of miRNAs) may contribute to allelic divergence in translation efficiency. Overall, our findings may improve the understanding of translational regulation in rice and provide information for the molecular basis of breading research.

bioinformatics↗

Multiple Cross Displacement Amplification Coupled with Gold Nanoparticles-Based Lateral Flow Biosensor for Detection of the Mobilized Colistin Resistance Gene mcr-1

Fast dissemination of the mobilized colistin resistance (mcr) gene mcr-1 in Enterobacteriaceae causes a huge threat to the treatment of severe infection. In the current report, a multiple cross displacement amplification (MCDA) coupled with the detection of amplified products by gold nanoparticles-based lateral flow biosensor (LFB) assay (MCDA-LFB) was established to identify the mcr-1 gene with simpleness, rapidity, specificity and sensitivity. The MCDA-LFB assay was performed at a isothermal temperature (63{degrees}C) for only 30 min during the amplification stage, and the reaction products were directly identified by using LFB which obtained the result with 2 min. The entire process of experiments, from templates extraction to result judging, was accomplished less than 60 min. For the analytical specificity of this method, all of the 16 mcr-1-producing strains were positive, and all of the non-mcr-1 isolates got the negative results. The sensitivity of mcr-1-MCDA-LFB assay was as little as 600 fg of plasmid DNA per reaction in pure culture, and approximately 4.5x103 CFU/mL (~4.5 CFU/reaction) in fecal samples spiked with 100 l of strains. Therefore, this technique established in the present study is suitable for the surveillance of mcr-1 gene in clinic and livestock industry.

molecular biology↗