Biology subjects

Xue, P.

Publications and source records attributed to Xue, P..

16 recordsLinked to original sources

bioRxiv2026

Label-free volumetric dynamic atlas of fresh mouse organs using dynamic full-field optical coherence tomography

Dynamic full-field optical coherence tomography (D-FFOCT) enables label-free visualization of tissue microarchitecture and endogenous intracellular dynamics. Here, we establish a volumetric atlas of ten fresh mouse organs using a mobile D-FFOCT imaging platform. The system enables large-area imaging of approximately 1 cm2 within 15 min with 1,024 frames per field of view, achieving 0.75-{micro}m lateral resolution and imaging depths of up to 200 {micro}m. Large-area mosaics, three-dimensional reconstructions, and comparisons with conventional histology reveal diverse organ-specific tissue architectures. Beyond morphological characterization, quantitative analysis of dynamic intensity and mean fluctuation frequency across nine organs reveals distinct dynamic signatures and tissue heterogeneity. Longitudinal imaging of brain, liver, and intestinal tissues further demonstrates organ-dependent temporal changes in endogenous dynamics following excision. Finally, we publicly release raw D-FFOCT imaging datasets from all ten organs, providing an open resource for quantitative tissue characterization, algorithm development, and reproducible research. Together, this study provides a comprehensive, openly accessible optical atlas of fresh mouse organs, establishing a foundation for systematic tissue characterization and advancing the broader application of D-FFOCT in biomedical research.

biophysics↗

bioRxiv2025

Complex Assembly and Activity States as Multifaceted Protein Attributes Explaining Phenotypic Variability

Cell function studies primarily focus on measuring overall molecular abundances while often overlooking critical clues--including protein modifications and molecular interaction networks--that critically determine the functional properties of the cell. In prior work, we introduced a suite of methods to reveal context-specific transcription factor-gene regulatory networks, kinase-substrate networks, and protein interaction networks and leveraged them to gain deeper insights into transcriptional regulation and signal transduction. However, the complex interdependencies between these networks are still elusive. To address this challenge, we introduce a multi-omics framework, aimed at harnessing measured or inferred protein activity in context-specific networks, which yields deeper functional insights into mechanisms underlying molecular phenotypes, compared to protein abundance alone. As proof of concept, we utilized progressively differentiated instances of HeLa CCL2 and Kyoto cell lines to explore the role of protein complexes and interactions in cell doubling time and susceptibility to Salmonella Typhimurium infection. Notably, this analysis underscores the pivotal role of protein interaction networks in linking molecular profiles to phenotypic outcomes, thus providing a highly generalizable framework for multi-omics dataset analysis.

systems biology↗

bioRxiv2025

Limited effect of short- to mid-term storage conditions on an Australian farmland soil RNA virome

Soils represent one of the largest and most diverse reservoirs of microbial life on Earth, yet their associated RNA viruses remain underexplored compared to animal and aquatic systems. Viral discovery in soils has been further limited by technical hurdles, particularly obtaining sufficient yields of high-quality RNA for sequencing. To address this, we evaluated a range of storage and preservation strategies, including the use of commercial preservative solutions and ultra-cold snap-freezing, followed by standardised RNA extraction, sequencing, and virus discovery pipelines. This work aimed to establish minimum sample storage requirements that maintain RNA integrity, generate sufficient RNA sequencing data, and subsequently enable reliable soil virome characterisation. While no preservative solution proved effective, "neat" soil samples were stable at 2-8{degrees}C and -30{degrees}C for at least two weeks, and at -80{degrees}C for at least three months, with no measurable reduction in RNA quality, sequencing data, or viral abundance and diversity. From 32 resulting sequencing libraries, we identified 1,475 putative novel RNA viruses, with the majority belonging to the microbe-associated phylum Lenarviricota. Several novel viruses formed divergent clusters with other environmentally derived sequences distantly related to traditionally animal-associated families such as the Astroviridae and Picornaviridae. Furthermore, unique clusters within the Picobirnaviridae, Alsuvurucetes, Ghabrivirales, and Amabiliviricetes comprised exclusively Australian viruses, suggesting instances of region-specific evolution. Together, these findings highlight soils as rich reservoirs of RNA viral diversity and provide practical minimum standards for storage, expanding opportunities to investigate the ecological and evolutionary roles of RNA viruses in terrestrial systems. ImportanceRNA viruses are the most abundant and diverse biological entities on Earth and are likely present in all other organisms and ecosystems, including soil-dwelling invertebrates, microbes, and plants. Despite this, their diversity and role in soil systems remains largely unknown. Methodological challenges in preserving and extracting sufficient quantities of RNA from soils have hindered the study of these communities. Here, we identified 1,475 previously undescribed RNA viruses in Australian soils while systematically testing different preservation strategies. The significance of our research lies in the demonstration that snap-freezing soil is a viable and robust storage strategy for at least three months, while also highlighting the extraordinary scale of viral diversity present in terrestrial environments. This work establishes a foundation for reliable exploration of terrestrial RNA viruses, improving the accessibility of more remote environmental viromes and enabling future efforts to integrate them into broader models of microbial ecology and ecosystem function.

microbiology↗

bioRxiv2024

Restoration of PKM1 improves functional maturation of human stem-cell derived-β cell by regulating PEP metabolism

Human stem cell-derived {beta} (SC-{beta}) cells still exhibit limited glucose response required for insulin secretion due to glycolytic bottlenecks, yet how these metabolic abnormalities impact glucose response and functional maturation of SC-{beta} cells remains unclear. In this study, we identified a metabolic checkpoint located at PEP accumulation that impeded the functional maturation, which was rescued by restoration of pyruvate kinase 1 (PKM1). Glucose-tracing metabolomics in human stem cell-derived islets revealed abnormal glycolytic PEP accumulation at resting condition, resulting in impaired calcium response and insulin secretion upon high glucose or glycolytic metabolite stimulation. Mechanistically, elevated PEP significantly raised intracellular basal calcium levels, leading to downregulated expression of genes involved in TCA cycle elucidated by single cell transcriptomics. Furthermore, the activity of pyruvate kinase, which metabolizes PEP, was notably reduced due to low PKM1 expression. By overexpressing PKM1, the impairment of TCA-related genes caused by PEP accumulation was reversed via modulating PEP metabolism, resulting in enhanced calcium responses and insulin secretion upon high glucose stimulation. Together, we discovered a novel role of PKM1-regulated PEP metabolism in mediating the functional maturation of human SC-{beta} cells. This study highlights the importance of metabolic reprogramming in human SC-{beta} cell maturation, advancing cell therapy approaches for diabetes treatment.

cell biology↗

bioRxiv2024

The interplay between electron transport chain function and iron regulatory factors influences melanin formation in Cryptococcus neoformans

Mitochondrial functions are critical for the ability of the fungal pathogen Cryptococcus neoformans to cause disease. However, mechanistic connections between key functions such as the mitochondrial electron transport chain (ETC) and virulence factor elaboration have yet to be thoroughly characterized. Here, we observed that inhibition of ETC complex III suppressed melanin formation, a major virulence factor. This inhibition was partially blocked upon loss of Cir1 or HapX, two transcription factors that regulate iron acquisition and use. In this regard, loss of Cir1 derepresses the expression of laccase genes as a potential mechanism to restore melanin, while HapX may condition melanin formation by controlling oxidative stress. We hypothesize that ETC dysfunction alters redox homeostasis to influence melanin formation. Consistent with this idea, inhibition of growth by hydrogen peroxide was exacerbated in the presence of the melanin substrate L-DOPA. Additionally, loss of the mitochondrial chaperone Mrj1, which influences the activity of ETC complex III and reduces ROS accumulation, also partially blocked antimycin A inhibition of melanin. The phenotypic impact of mitochondrial dysfunction was consistent with RNA-Seq analyses of WT cells treated with antimycin A or L-DOPA, or cells lacking Cir1 that revealed influences on transcripts encoding mitochondrial functions (e.g., ETC components and proteins for Fe-S cluster assembly). Overall, these findings reveal mitochondria-nuclear communication via ROS and iron regulators to control virulence factor production in C. neoformans. IMPORTANCEThere is a growing appreciation of the importance of mitochondrial functions and iron homeostasis in the ability of fungal pathogens to sense the vertebrate host environment and cause disease. Many mitochondrial functions such as heme and iron-sulfur cluster biosynthesis, and the electron transport chain (ETC), are dependent on iron. Connections between factors that regulate iron homeostasis and mitochondrial activities are known in model yeasts and are emerging for fungal pathogens. In this study, we identified connections between iron regulatory transcription factors (e.g., Cir1 and HapX) and the activity of complex III of the ETC that influence the formation of melanin, a key virulence factor in the pathogenic fungus Cryptococcus neoformans. This fungus causes meningoencephalitis in immunocompromised people and is a major threat to the HIV/AIDS population. Thus, understanding how mitochondrial functions influence virulence may support new therapeutic approaches to combat diseases caused by C. neoformans and other fungi.

microbiology↗

bioRxiv2023

DIP-MS: A novel ultra-deep interaction proteomics for the deconvolution of protein complexes

Most, if not all, proteins are organized in macromolecular assemblies, which represent key functional units regulating and catalyzing the majority of cellular processes in health and disease. Ever-advancing analytical capabilities promise to pinpoint lesions in proteome modularity driving disease phenotypes. Affinity purification of the protein of interest combined with LC-MS/MS (AP-MS) represents the method of choice to identify interacting proteins. The composition of complex isoforms concurrently present in the AP sample can however not be resolved from a single AP-MS experiment but requires computational inference from multiple time-and resource-intensive reciprocal AP-MS experiments. In this study we introduce Deep Interactome Profiling by Mass Spectrometry (DIP-MS) which combines affinity enrichment with BN-PAGE separation, DIA mass spectrometry and deep-learning-based signal processing to resolve complex isoforms sharing the same bait protein in a single experiment. We applied DIP-MS to probe the organisation of the human prefoldin (PFD) family of complexes, resolving distinct PFD holo- and sub-complex variants, complex-complex interactions and complex isoforms with new subunits that were experimentally validated. Our results demonstrate that DIP-MS can reveal proteome modularity at unprecedented depth and resolution and thus represents a critical steppingstone to relate a proteome state to phenotype in both healthy and diseased conditions.

systems biology↗

bioRxiv2022

A new LD protein, ApoL6 disrupts the Perilipin 1-HSL interaction to inhibit lipolysis

ApoL6 is a new LD-associated protein containing an apoprotein-like domain, expressed mainly in adipose tissue, specifically in adipocytes. ApoL6 expression is low in fasting but induced upon feeding. ApoL6 knockdown results in smaller LD with lower triglyceride (TAG) content in adipocytes, while ApoL6 overexpression causes larger LD with higher TAG content. We show that ApoL6 effect in adipocytes is by inhibition of lipolysis. While ApoL6, Perilipin 1 (Plin1) and HSL can form a complex on LD, C-terminal domain of ApoL6 directly interacts with Plin1, to compete with Plin1 binding to HSL through Plin1 N-terminal domain, thereby keeping HSL in a "stand by" status. Thus, ApoL6 ablation decreases WAT mass, protecting mice from diet-induced obesity, while adipose overexpression increases WAT mass to bring obesity and insulin resistance with hepatosteatosis, making ApoL6 a potential future target against obesity and diabetes.

molecular biology↗

bioRxiv2022

Hormone-induced enhancer assembly requires an optimal level of hormone receptor multivalent interactions

Transcription factors (TFs) activate enhancers to drive cell-specific gene programs in response to signals, but our understanding of enhancer assembly during signaling events is incomplete. Here, we show that Androgen Receptor (AR), a steroid hormone-regulated transcription factor, forms condensates through multivalent interactions in response to androgen signaling to orchestrate enhancer assembly. We demonstrate that the intrinsically disordered N-terminal domain (NTD) of AR drives 1,6-Hexanediol-sensitive condensate formation and that NTD deletion or aromatic residue mutation reduces AR self-association and abolishes AR transcriptional activity. AR NTD can be substituted by intrinsically disordered regions (IDRs) from selective proteins for AR condensation capacity and transactivation function. Surprisingly, strengthened AR condensation capacity caused by extending the polyQ tract within AR NTD also leads to impaired transcriptional activity without affecting AR binding on enhancers. Furthermore, either NTD deletion or polyQ extension reduces heterotypic multivalent interactions between AR and other enhancer components. These results suggest the importance of an optimal level of AR condensation in mediating AR-AR homotypic and AR-cofactor heterotypic interactions to regulate enhancer assembly in response to signals. Our study supports the notion that alteration of the fine-tuned multivalent IDR-IDR interactions might underlie AR-related human pathologies, thereby providing novel molecular insights for potential therapeutic strategies to treat prostate cancer and other AR-involved diseases by targeting AR multivalent interactions.

molecular biology↗

bioRxiv2022

PlasmidMaker: a Versatile, Automated, and High Throughput End-to-End Platform for Plasmid Construction

Plasmids are used extensively in basic and applied biology. However, design and construction of plasmids, specifically the ones carrying complex genetic information, remains one of the most time-consuming, labor-intensive, and rate-limiting steps in performing sophisticated biological experiments. Here, we report the development of a versatile, robust, automated end-to-end platform named PlasmidMaker that allows error-free construction of plasmids with virtually any sequences in a high-throughput manner. This platform consists of a most versatile DNA assembly method using Pyrococcus furiosus Argonaute (PfAgo)-based artificial restriction enzymes, a user-friendly frontend for plasmid design, and a backend that streamlines the workflow and integration with a robotic system. As a proof of concept, we used this platform to generate 101 plasmids from six different species ranging from 5 to 18 kb in size from up to 11 DNA fragments within 3 days. PlasmidMaker should greatly expand the potential of synthetic biology.

synthetic biology↗

bioRxiv2021

Rapid profiling of protein complex re-organization in perturbed systems

Protein complexes constitute the primary functional modules of cellular activity. To respond to perturbations, complexes undergo changes in their abundance, subunit composition or state of modification. Understanding the function of biological systems requires global strategies to capture this contextual state information on protein complexes and interaction networks. Methods based on co-fractionation paired with mass spectrometry have demonstrated the capability for deep biological insight but the scope of studies using this approach has been limited by the large measurement time per biological sample and challenges with data analysis. As such, there has been little uptake of this strategy beyond a few expert labs into the broader life science community despite rich biological information content. We present a rapid integrated experimental and computational workflow to assess the re-organization of protein complexes across multiple cellular states. It enables complex experimental designs requiring increased sample/condition numbers. The workflow combines short gradient chromatography and DIA/SWATH mass spectrometry with a data analysis toolset to quantify changes in complex organization. We applied the workflow to study the global protein complex rearrangements of THP-1 cells undergoing monocyte to macrophage differentiation and a subsequent stimulation of macrophage cells with lipopolysaccharide. We observed massive proteome organization in functions related to signaling, cell adhesion, and extracellular matrix during differentiation, and less pronounced changes in processes related to innate immune response induced by the macrophage stimulation. We therefore establish our integrated differential pipeline for rapid and state-specific profiling of protein complex organization with broad utility in complex experimental designs.

systems biology↗

bioRxiv2020

A non-canonical EZH2 function sensitizes solid tumors to genotoxic stress

Drugs that block the activity of the methyltransferase EZH2 are in clinical development for the treatment of non-Hodgkin lymphomas harboring gain-of-function EZH2 mutations that enhance its polycomb repressive function. In contrast, in castration-resistant prostate cancer (CRPC) we have previously reported that EZH2 plays a non-canonical role as a transcriptional activator. In this setting, we now show that EZH2 inhibitors can also block the non-canonical activity of EZH2 and inhibit the growth of CRPC cells. Gene expression and epigenomic profiling of cells treated with EZH2 inhibitors demonstrated that rather than de-repressing tumor suppressor genes silenced by PRC2, EZH2 inhibitors downregulate a set of DNA repair genes that are directly regulated by EZH2. In addition, genome-wide CRISPR/Cas9-mediated loss-of-function screens in the presence of EZH2 inhibitors identified these DNA repair genes to underlie the growth-inhibitory function of these compounds. Interrogation of public data from diverse solid tumor types expressing wild-type EZH2 showed that expression of DNA damage repair genes is significantly correlated with cellular sensitivity to EZH2 inhibitors. Consistent with these findings, treatment of CRPC cells with EZH2 inhibitors dramatically enhanced their sensitivity to genotoxic stress. These studies reveal a previously unappreciated mechanism of action of EZH2 inhibitors and provide a mechanistic basis for potential new combination cancer therapies.

cancer biology↗

bioRxiv2020

Systematic protein complex profiling and differential analysis from co-fractionation mass spectrometry data

Protein complexes, macro-molecular assemblies of two or more proteins, play vital roles in numerous cellular activities and collectively determine the cellular state. Despite the availability of a range of methods for analysing protein complexes, systematic analysis of complexes under multiple conditions has remained challenging. Approaches based on biochemical fractionation of intact, native complexes and correlation of protein profiles have shown promise, for instance in the combination of size exclusion chromatography (SEC) with accurate protein quantification by SWATH/DIA-MS. However, most approaches for interpreting co-fractionation datasets to yield complex composition, abundance and rearrangements between samples depend heavily on prior evidence. We introduce PCprophet, a computational framework to identify novel protein complexes from SEC-SWATH-MS data and to characterize their changes across different experimental conditions. We demonstrate accurate prediction of protein complexes (AUC >0.99 and accuracy around 97%) via five-fold cross-validation on SEC-SWATH-MS data, show improved performance over state-of-the-art approaches on multiple annotated co-fractionation datasets, and describe a Bayesian approach to analyse altered protein-protein interactions across conditions. PCprophet is a generic computational tool consisting of modules for data pre-processing, hypothesis generation, machine-learning prediction, post-prediction processing, and differential analysis. It can be applied to any co-fractionation MS dataset, independent of separation or quantitative LC-MS workflow employed, and to support the detection and quantitative tracking of novel protein complexes and their physiological dynamics.

systems biology↗

bioRxiv2020

Phytochrome mediated responses in Agrobacterium fabrum: growth, swimming, plant infection and interbacterial competition

The soil bacterium Agrobacterium fabrum C58 infects plants by a unique DNA transfer mechanism. A. fabrum has two phytochrome photoreceptors, Agp1 and Agp2. We found that DNA transfer into plants by A. fabrum is down regulated by light and that phytochrome knockout mutants have diminished DNA transfer rates. The regulation pattern matches with that of bacterial conjugation reported earlier. Growth, swimming and interbacterial competition were also affected in phytochrome knockout mutants, although these effects were often not affected by light. We can thus distinguish between light-regulated and light-independent phytochrome responses. In microarray studies, transcription of only 4 genes was affected by light, indicating that most light responses are regulated post-transcriptionally. In a mass spectrometery-based proteomic study, 24 proteins were different between light and dark grown bacteria, whereas 382 proteins differed between wild type and phytochrome knockout mutants, pointing again to light-dependent and light-independent roles of Agp1 and Agp2.

microbiology↗

bioRxiv2019

SECAT: Quantifying differential protein-protein interaction states by network-centric analysis

Protein-protein interactions (PPIs) play critical functional and regulatory roles in virtually all cellular processes. They are essential for the formation of macromolecular complexes, which in turn constitute the basis for extended protein interaction networks that determine the functional state of a cell. We and others have previously shown that chromatographic fractionation of native protein complexes in combination with bottom-up mass spectrometric analysis of consecutive fractions supports the multiplexed characterization and detection of state-specific changes of protein complexes. In this study, we describe a computational approach that extends the analysis of data from the co-fractionation / mass spectrometric analysis of native complexes to the level of PPI networks, thus enabling a qualitative and quantitative comparison of the proteome organization between samples and states. The Size-Exclusion Chromatography Algorithmic Toolkit (SECAT) implements a novel, network-centric strategy for the scalable and robust differential analysis of PPI networks. SECAT and its underlying statistical framework elucidate differential quantitative abundance and stoichiometry attributes of proteins in the context of their PPIs. We validate algorithm predictions using publicly available datasets and demonstrate that SECAT represents a more scalable and effective methodology to assess protein-network state and that our approach thus obviates the need to explicitly infer individual protein complexes. Further, by differential analysis of PPI networks of HeLa cells in interphase and mitotic state, respectively, we demonstrate the ability of the algorithm to detect PPI network differences and to thus suggest molecular mechanisms that differentiate cellular states.

systems biology↗

bioRxiv2019

Coordinate Enhancer Reprogramming by GATA3 and AP1 Promotes Phenotypic Plasticity to Achieve Breast Cancer Endocrine Resistance

Acquired therapy resistance is a major problem for anticancer treatment, yet the underlying molecular mechanisms remain unclear. Using an established breast cancer cellular model for endocrine resistance, we show that hormone resistance is associated with enhanced phenotypic plasticity, indicated by a general downregulation of luminal/epithelial differentiation markers and upregulation of basal/mesenchymal invasive markers. Our extensive omics studies, including GRO-seq on enhancer landscapes, demonstrate that the global enhancer gain/loss reprogramming driven by the differential interactions between ER and other oncogenic transcription factors (TFs), predominantly GATA3 and AP1, profoundly alters breast cancer transcriptional programs. Our functional studies in multiple biological systems including culture and xenograft models of MCF7 and T47D lines support a coordinate role of GATA3 and AP1 in enhancer reprogramming that promotes phenotypic plasticity and endocrine resistance. Collectively, our study implicates that changes in TF-TF and TF-enhancer interactions can lead to genome-wide enhancer reprogramming, resulting in transcriptional dysregulations that promote plasticity and cancer therapy-resistance progression.

cancer biology↗

bioRxiv2018

A direct comparison of four high risk human papilloma virus tests versus the cobas test for detecting cervical intraepithelial neoplasia and cervical cancer

This study is to evaluate performances and genotyping capabilities of four human papilloma virus (HR-HPV) tests based on real-time polymerase chain reaction (PCR) technology platforms compared with the cobas test. Discordant results were further analyzed using INNO-LiPA HPV genotyping test, the gold standard laboratory test to determine presence and type of HPV infection. Over 200 samples from Hospital patients were collected and analyzed using five HR-HPV tests. Women with positive test results were referred directly to colposcopy. If a positive result was returned, biopsies were administered for pathological classification. Clinical performances and genotyping capabilities between the four HR-HPV and cobas tests were compared and contrasted. High levels of agreement were observed, though all HR-HPV tests presented discrepancies compared with the cobas test. Cervical intraepithelial neoplasia Grade 2 or higher lesions (CIN2+) was set as the threshold, and all five tests performed with equally high sensitivity. Lower levels of specificity were observed across all five tests. Results suggest the four HR-HPV tests analyzed are as effective as the cobas test in genotyping capacities and diagnosing CIN. Therefore, these test kits should be used for HPV screening, especially in developing nations because they are cost effective and reliable. Minor discrepancies between tests are generally unavoidable though this may add complexity to the clinical decision-making process. As such, we recommend that efforts be made to standardize HPV genotyping tests as well as to optimize clinical sensitivity and specificity. Focusing on these issues will drive the development of HPV detection techniques, therefore save lives.

epidemiology↗