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Li, Y.-C.

Publications and source records attributed to Li, Y.-C..

6 recordsLinked to original sources

AetherXeno: an allele-resolved receptor-occupancy atlas for regulatory pharmacogenomics

Motivation: Interpreting noncoding pharmacogenomic variants requires identifying the regulatory program that may be perturbed and the direction of the effect, information not supplied by population frequency or general regulatory annotations. Results: We developed AetherXeno, an allele-resolved atlas that scores all substitutions across 8,691 experimentally supported elements for PXR, FXR and AhR and connects 17.27 million variants to evidence matched by exact allele. Across the six paired comparisons, the gain in Spearman correlation ranged from 0.039 to 0.334. Every regional bootstrap interval excluded zero. Homology exclusion preserved these findings, while motif core and liver expression enrichment supported biological organization of the score landscape. The browser, programmatic interface and bulk files expose the same versioned records from individual variants to cohort analyses. Availability and implementation: The web resource is available at https://aetherxeno.org and the versioned data at doi:10.5281/zenodo.20753827.

bioinformatics↗

The rapid diversification of Boletales is linked to Early Eocene and Mid-Miocene Climatic Optima

O_LIInvestigating the mechanisms that underpin the diversity and distribution patterns of species is fundamental in ecology and evolution. However, the study of fungi, particularly the ectomycorrhizal group, has been relatively constrained in this field. C_LIO_LIWe conducted a high-resolution phylogenomic analysis of Boletales, an ecologically and economically significant group of fungi, covering 83 genera across 15 families. We subsequently investigated its evolutionary history using sequences at four genes obtained from 984 species across 121 genera within 15 families. C_LIO_LIThe findings unveiled that Boletales likely originated in Early Jurassic and underwent two remarkable episodes of rapid diversification, commencing in early Eocene ([~]54 Mya) and early Miocene ([~]17 Mya) epochs. The notable surges were predominantly driven by ectomycorrhizal clades, with a specific emphasis on East Asia and North America. These expansions were strongly correlated with the warm-humid paleoclimates during the Early Eocene Climatic Optimum and Mid-Miocene Climatic Optimum, as well as the rapid expansion of Fagales and Pinaceae hosts. C_LIO_LIThis study provides novel insights into the spatiotemporal evolution of fungi, highlighting the synergistic impact of abiotic factors, such as warm and humid paleoclimates, and the biotic factor of rapid diversification of host plants on the fungal diversification. C_LI

evolutionary biology↗

Cooperation between physiological defenses and immune resistance produces asymptomatic carriage of a lethal bacterial pathogen

Animals have evolved two defense strategies to survive infections. Antagonistic strategies include mechanisms of immune resistance that operate to sense and kill invading pathogens. Cooperative or physiological defenses mediate host adaptation to the infected state, limiting physiological damage and disease, without killing the pathogen, and have been shown to cause asymptomatic carriage and transmission of lethal pathogens. Here we demonstrate that physiological defenses cooperate with the adaptive immune response to generate long-term asymptomatic carriage of the lethal enteric murine pathogen, Citrobacter rodentium. Asymptomatic carriage of genetically virulent C. rodentium provided immune resistance against subsequent infections. Host immune protection was dependent on systemic antibody responses and pathogen virulence behavior, rather than the recognition of specific virulent factor antigens. Finally, we demonstrate that an avirulent strain of C. rodentium in the field has background mutations in two genes that are important for LPS structure. Our work reveals novel insight into how asymptomatic infections can arise mechanistically with immune resistance, mediating exclusion of phenotypically virulent enteric pathogen to promote asymptomatic carriage.

immunology↗

Multiplexed identification of RAS paralog imbalance as a driver of lung cancer growth

Oncogenic KRAS mutations occur in approximately 30% of lung adenocarcinoma. Despite several decades of effort, oncogenic KRAS-driven lung cancer remains difficult to treat, and our understanding of the positive and negative regulators of RAS signaling is incomplete. To uncover the functional impact of diverse KRAS-interacting proteins on lung cancer growth in vivo, we used multiplexed somatic CRISPR/Cas9-based genome editing in genetically engineered mouse models with tumor barcoding and high-throughput barcode sequencing. Through a series of CRISPR/Cas9 screens in autochthonous lung tumors, we identified HRAS and NRAS as key suppressors of KRASG12D-driven tumor growth in vivo and confirmed these effects in oncogenic KRAS-driven human lung cancer cell lines. Mechanistically, RAS paralogs interact with oncogenic KRAS, suppress KRAS-KRAS interactions, and reduce downstream ERK signaling. HRAS mutations identified in KRAS-driven human tumors partially abolished this effect. Comparison of the tumor-suppressive effects of HRAS and NRAS in KRAS- and BRAF-driven lung cancer models confirmed that RAS paralogs are specific suppressors of oncogenic KRAS-driven lung cancer in vivo. Our study outlines a technological avenue to uncover positive and negative regulators of oncogenic KRAS-driven cancer in a multiplexed manner in vivo and highlights the role of RAS paralog imbalance in oncogenic KRAS-driven lung cancer.

cancer biology↗

Retinal Vessels Detection Using Convolutional Neural Networks in Fundus Images

Computer-aided detection (CAD) system is a realistic option for physicians to screen fundus images. Automated segmentation of retinal vessel is in fundus important step to identify the retinal disease region. However, identification of the retinal disease region accurately is still challenging due to the varied distribution of blood vessel on noisy and low contrast fundus images. Healthcare system has been changing significantly with the emergence of machine learning (ML), deep learning (DL) and artificial intelligence (AI) in recent year. Retinal vessel detection is one such area of application of deep learning, for improving the accuracy of detection and segmentation and the quality of patient care. Recently, the convolutional neural networks (CNN) have been applied to the detection of the retinal vessel from fundus images and have demonstrated promising results. The range of accuracy of the CNN model was 0.91-0.95 and the area under the receiver operating curve was 0.09-0.98. Therefore, CNN may play a crucial role in determining the therapeutic methods and detecting the retinal vessel accurately in an individual manner. In this survey, we described the use of CNN in fundus imaging, especially focused on CNN technique, clinical application for retinal vessel detection and future prospective.

bioinformatics↗

Facile real time detection of membrane colocalization of RAS superfamily GTPase proteins in living cells

Members of the RAS family of GTPases (KRAS4A, KRAS4B, HRAS, and NRAS) are the most frequently mutated oncogenes in human cancers. The CAAX motif in the C-terminal hypervariable region (HVR-CAAX domain) contains the cysteine residue that is critical for protein prenylation that enables RAS protein membrane localization, homodimer/oligomer formation, and activation of effector signaling and oncogenic activity. However, it remains unclear if RAS can interact with other prenylated proteins, and if so, how this impacts RAS function. Here we use a newly developed quantifiable Recombinase enhanced Bimolecular Luciferase Complementation strategy (ReBiL2.0) to investigate some of the requirements for RAS superfamily small GTPase protein interactions, and whether this requires cell membrane localization. ReBiL enables such analyses to be done at physiologic expression levels in living cells. Our results confirm that the C-terminal prenylated HVR-CAAX domain is sufficient to direct KRAS and heterologous proteins to colocalize in the cell membrane. We discovered that KRAS also colocalizes with a subset of small GTPase superfamily members including RAC1, RAC2 and DIRAS3 in a prenylation-dependent manner. KRAS colocalization or co-clustering with heterologous proteins can impact KRAS downstream signaling. ReBiL2.0 thus provides a rapid, simple and straightforward method to identify and characterize the colocalization of membrane-associated proteins and to discover agonists and antagonists thereof.

cancer biology↗