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Guan, M.

Publications and source records attributed to Guan, M..

At least 19 recordsLinked to original sources

Structure of influenza D virus NS1 reveals a novel Zn-binding site and ssRNA-binding activity

Influenza D virus (IDV) is an emerging pathogen associated with bovine respiratory disease and has potential for zoonotic transmission. Although nonstructural protein 1 (NS1) is a major virulence factor in influenza A and B viruses, the structure and function of IDV NS1 remain poorly defined. Here, we determined crystal structures of the IDV NS1 N-terminal RNA-binding domain (NTD) and C-terminal effector domain (CTD). The NTD retains the conserved homodimeric six-helix fold, whereas the CTD adopts a distinct architecture containing a novel Zn2+-binding site. IDV NS1 CTD preferentially binds single-stranded RNA, and mutagenesis identified lysine and arginine residues critical for this activity. Single-residue substitutions disrupting either the Zn2+-binding site or RNA-binding interface prevented recovery of infectious recombinant IDV. These findings reveal distinct structural and functional features of IDV NS1 and establish the importance of CTD integrity for viral replication. Conservation of key CTD residues in influenza C virus NS1 suggests shared structural features that distinguish influenza C and D virus NS1 proteins from their influenza A and B counterparts.

biochemistry↗

Pulmonary colonization of Candida albicans drives breast cancer lung metastasis via candidalysin

The intratumoral mycobiome is emerging as a key modulator of cancer progression, with specific fungal taxa as potential biomarkers. However, whether and how mycobiomes colonizing distant organs contribute to tumor evolution remains largely unexplored. Here, we identify selective enrichment of Candida albicans in breast cancer lung metastases. Mechanistically, the fungal virulence factor candidalysin activates pulmonary mast cells, which release chemotactic mediators that expand immunosuppressive populations and suppress cytotoxic lymphocyte activity, remodeling the lung into a metastasis-permissive microenvironment. Analysis of clinical isolates and isogenic mutants further demonstrates that candidalysin secretion levels dictate metastasis-promoting potential. Informed by these findings, we developed a combination regimen that concurrently eliminates fungal colonization, stabilizes mast cells, and reverses the immunosuppressive microenvironment, thereby significantly curtailing metastatic progression. Collectively, our study establishes pulmonary C. albicans colonization as a driver of breast cancer lung metastasis and provides a mechanistic framework for targeting mycobiome-host interactions in metastatic disease.

cancer biology↗

Using Natural Vector Method for Population Genomic Analysis on Human Mitochondrial Genome Data

The natural vector method is an important method for the analysis of biological sequences. In this study, we applied this method to population genetic analysis, with the core purpose of using it to evaluate the characteristics of a set of sequences rather than just pairwise comparison. We used the mitochondrial genome dataset from the human 1000 Genomes Project as a dataset to verify the feasibility of this improved natural vector method. The results showed that the modified natural vector method could be used for various population genetic approaches at least in the sense of population average, including the calculation of principal component analysis, population structure analysis and genetic diversity parameters. The results were in good agreement with those based on traditional molecular genetic markers such as SNP. The new method validates the feasibility of natural vector method for population genetic analysis and provides a framework for the application of matchless pair method to population genomic analysis on a wider scale.

genetics↗

Fast and Accurate Photon-Transport Modeling based on Foundation-Model-Encoded Implicit Neural Surrogate towards Optimized Near-Infrared Brain Stimulation

Clinical treatment planning for near-infrared (NIR) neuromodulation requires patient-specific dosimetry to optimize light fluence (LF) delivery to cortical targets. The gold-standard Monte Carlo photon-transport forward solver is accurate but computationally expensive and non-differentiable for personalized inverse design across subjects. Here, we present PhomiNeuro, a foundation-model-encoded differentiable surrogate for time-resolved LF modeling and pathology-guided inverse design. A pretrained 3D medical imaging foundation model (VISTA3D) was domain-adapted to 285 training head models annotated with optical properties, and then coupled to an implicit neural representation (INR) that predicts LF at arbitrary spatiotemporal coordinates. Regularized by a time-dependent diffusion-equation residual, it demonstrated superior fidelity in 84 held-out participants, and ablations identified VISTA3D-derived anatomical priors as dominant and physics regularization as complementary. PhomiNeuro enables fast and robust queries of LF and its gradients with respect to illumination parameters for targets guided by individual structural magnetic resonance imaging and amyloid positron emission tomography, achieving 466-fold per-iteration speedup and 167-fold end-to-end optimization speedup. Explanatory analyses of LF delivery variability, including sex differences and amyloid status, identified structural variations as the primary drivers. These results position PhomiNeuro as a highly extensible translational framework toward personalized treatment planning and digital twin development in precision neuromodulation.

bioengineering↗

A transcriptional regulator gene TRG1 of Trichoderma longibrachiatum is involved in the regulation of peptaibols synthesis

Trichoderma species are recognized for their robust biocontrol capacity, primarily due to the production of peptaibols, potent secondary metabolites that exhibit antibacterial properties, induce cell apoptosis, and enhance plant disease resistance. To elucidate the regulatory mechanism of peptaibol synthesis, we investigated the role of a transcription regulator gene TRG1 (designated as TLTRG1), which we identified within a non-ribosomal peptide synthetase (NRPS) gene cluster of T. longibrachiatum SMF2. We successfully created a{Delta} TRG1 gene knockout mutantusing homologous recombination. Phenotypic analysis indicated that the{Delta} TRG1 mutant maintained wild-type growth rate, colony morphology, and spore production. However,{Delta} TRG1 exhibited a significantly reduced inhibition rate against the plant pathogen Botrytis cinerea and a lower efficacy in controlling gray mold on detached rose leaves. High-performance liquid chromatography (HPLC) analysis provided direct molecular evidence, showing that peptaibol production in the mutant was 2.5 times lower than that of the wild-type strain. These findings conclusively establish that TRG1 functions as a key positive transcriptional regulator essential for high-yield peptaibol biosynthesis by modulating NRPS gene expression. This gene represents a critical molecular target for bioengineering strategies aimed at enhancing the biocontrol efficacy of Trichoderma strains. The Importance sectionTrichoderma species are known to produce peptaibols, which exhibit antibacterial properties, induce cell apoptosis, and enhance plant disease resistance. However, the mechanisms underlying the biosynthesis and regulation of peptaibols remain unclear. In this study, we investigated the role of a transcription regulator gene located within a non-ribosomal peptide synthetase (NRPS) gene cluster of T. longibrachiatum SMF2, which we designated as TLTRG1 (TRG1). Phenotypic analysis indicated the inhibition rate of {Delta}TRG1 against Botrytis cinerea and its effectiveness in controlling gray mold were significantly reduced compared to the WT strain. High-performance liquid chromatography (HPLC) analysis revealed that the production of peptaibols in the mutant was significantly decreased. These findings suggest that the TRG1 gene may play a crucial role in regulating the expression of NRPS genes, thereby affecting the biosynthesis of peptaibols. Therefore, it can be concluded that the gene TRG1 is a molecular target for bioengineering strains with enhanced biocontrol efficacy.

microbiology↗

Comparative Analysis of Pathology Foundation Models for Automated Detection of Tertiary Lymphoid Structures in H&E-Stained Digital Pathology Images

Tertiary lymphoid structures (TLS) have been observed in solid tumors and have been associated with better outcomes in patients treated with immunotherapy, but their dynamic nature makes identifying TLS in clinical samples challenging. Recently, pathology foundation models have emerged as powerful tools in computational pathology. In this study, we aimed to develop a computational tool capable of identifying TLS across different cancer types. To this end, we utilized multiple pathology foundation models, along with the ImageNet-pretrained ResNet50 as a baseline, to identify TLS in pancreatic ductal adenocarcinoma (PDAC) and head and neck squamous cell carcinoma (HNSCC) using hematoxylin and eosin (H&E) stained images from The Cancer Genome Atlas (TCGA) and a licensed Real-World Evidence (RWE) cohort. Both pathologist-annotated and transcriptomic signature-based TLS outcomes were employed for performance assessment. Pathologist-identified TLS-positive tumors showed higher expression of TLS signatures in both diseases. Among the models tested, PLIP and CTransPath exhibited strong performance in identifying TLS within PDAC samples (AUC = 0.94 and 0.89, respectively). However, all models struggled in the analysis of HNSCC, likely due to the increased heterogeneity of the tumor microenvironment (TME). Despite their overall utility in detecting TLS in PDAC, all foundation models demonstrated poor performance in predicting transcriptomic signature-based outcomes in both PDAC and HNSCC. This suggests that TLS signatures may reflect broader or more transient aspects of TLS biology, whereas pathology-based assessment anchors on visible morphological features, more closely aligned with the focus of foundation model training. These findings highlight the potential of advanced pathology foundation models for TLS detection and broader tumor immune profiling tasks. These models can also be utilized on routinely collected patient biosamples with nominal costs. However, further refinement is needed to enhance their utility in tumors with more complex TME. Additionally, the identification of transcriptomics-based biomarkers from H&E images remains a significant challenge, despite advancements in digital pathology.

bioinformatics↗

Targeting HMGA1-driven leukemic transformation in myeloproliferative neoplasms with pacritinib

Progression of myeloproliferative neoplasms (MPNs) to secondary acute myeloid leukemia (sAML) is a lethal transition lacking reliable early biomarkers and effective therapies. Integrating multi-omics analyses, a cohort of 240 patient biopsies, and functional studies, we identify High Mobility Group A1 (HMGA1) as a critical driver and predictor of this transformation. HMGA1 expression, readily detectable by immunohistochemistry, progressively increases from chronic MPN phases to sAML, outperforming established markers (CD34/CD117) in predicting impending leukemic transformation (AUC = 0.96). Mechanistically, HMGA1 cooperates with JAK2V617F and TP53 mutations to promote leukemogenesis. Clinically, high HMGA1 levels correlate with resistance to first-generation JAK inhibitors and portend poor overall survival. Importantly, the next generation JAK2/FLT3 inhibitor pacritinib abrogates HMGA1-driven proliferation and significantly extends survival in preclinical models, offering an immediate therapeutic strategy for this high-risk population. Our findings establish HMGA1 as an actionable biomarker for risk stratification and early intervention, and a therapeutic target to overcome therapeutic resistance in MPN-sAML. HighlightsO_LIHMGA1 IHC staining serves as a readily implementable biomarker, outperforming existing marker for early prediction of MPN progression to sAML and identifying patients at high risk. C_LIO_LIElevated HMGA1 expression correlates with resistance to first-generation JAK inhibitors and predicts poor overall survival in MPN-sAML patients, highlighting a critical unmet therapeutic need. C_LIO_LIThe next-generation JAK2 inhibitor pacritinib effectively overcomes HMGA1-driven aggressive disease and therapy resistance, offering a rational, clinically available treatment strategy for HMGA1-high MPN-sAML. C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/657170v1_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@18b835org.highwire.dtl.DTLVardef@e5b31dorg.highwire.dtl.DTLVardef@5245caorg.highwire.dtl.DTLVardef@163f5de_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Engineering novel AAV capsids by global de-targeting and subsequent muscle-specific tropism in mice and NHPs

Recombinant adeno-associated viral (rAAV) vectors are a potent tool, but their clinical application is restricted by insufficient target tissue transduction and liver toxicity. We employed a novel two-step engineering strategy to create novel rAAV capsids with global tissue de-targeting, then produced strong tissue-specific expression by adding a peptide sequence. We created a novel capsid, AAV.Zero1, with globally de-targeted transduction by loop swapping domains from AAV9 into AAV2. Making an R585A substitution (AAV.Zero2) re-targeted tissues but deleting residues 585-587 (AAV.Zero3) abrogated transduction. Inserting a myogenic peptide into AAV.Zero3 produced a novel capsid (AAV.eM) with strong muscle-specific transgene expression while maintaining minimal off-target expression, including in liver, which was conserved in two mouse strains and non-human primates. AAV.eM showed similar expression as the leading myotropic vector MyoAAV.4A but had a more favorable safety profile. Importantly, AAV.eM was able to functionally rescue a mouse model of Duchenne Muscular Dystrophy following systemic delivery of a micro-dystrophin gene. Thus, AAV.eM is an improved myotropic rAAV capsid that de-targets other tissues, especially the liver, and proof-of-concept for a platform to create capsids with specific properties that translate across species by addition of peptides onto low transduction backbones.

bioengineering↗

Poor sleep impairs immune responses and influenza vaccine protection

Disrrupted sleep, a common occurrence among shift workers, older adults, and individuals with sleep disorders, is increasingly recognized as a potential factor interfering with vaccine efficacy. Using a mouse model, we show that two weeks of chronic sleep fragmentation (CSF) before and during influenza vaccination significantly impair humoral immunity and reduce protection against lethal viral challenge. CSF-exposed mice exhibited lower neutralizing antibody titers, diminished IgG subclass responses, and reduced survival after viral challenge, despite preserved antibody binding avidity. Single-cell RNA sequencing and immune receptor profiling revealed altered B cell maturation, abnormal germinal center activation, and plasma cell stress, characterized by activation of unfolded protein response and oxidative stress pathways. CSF also reprogrammed B-cell signaling and disrupted coordination with T-cells. Together, this study showed that CSF compromises vaccine-induced immune responses by affecting multistage of B-cell differentiation, underscoring the importance of considering sleep health in vaccination strategies for vulnerable populations. One Sentence SummaryPoor sleep weakens both the magnitude and quality of immune responses, compromising the protective efficacy of influenza vaccination.

immunology↗

Dentification of the Sorghum TMCO Gene Family and Differential Expression Analysis Under Aphid Infestation

The three-domain multicopper oxidase (TMCO) family, the largest subfamily of multicopper oxidases, plays a crucial role in plant growth, development, and responses to biotic stresses. To investigate the expression characteristics of the SbTMCO gene family under aphid infestation, a genome-wide identification and analysis of TMCO family members in sorghum were conducted using bioinformatics methods. Transcriptome data and qRT-PCR were utilized to preliminarily examine sorghums responses to aphid stress. The results revealed 42 TMCO genes in the sorghum genome, distributed across 10 chromosomes and classified into five subgroups. Members within the same subgroup displayed similar physicochemical properties, gene structures, and conserved motifs. Collinearity analysis suggested that tandem duplication and segmental duplication were the primary drivers of TMCO gene expansion in sorghum. Cis-acting element analysis identified multiple jasmonic acid (MeJA) and abscisic acid (ABA) responsive elements among SbTMCO genes. Gene expression analysis, based on RNA-seq and qRT-PCR, confirmed the relative expression levels of TMCO genes under aphid stress. This study establishes a foundation for exploring the anti-aphid functions of SbTMCO genes and provides recommendations and directions for further research on this gene family.

molecular biology↗

Assembly of Hierarchical Multiphase Condensates Using Designer Surfactant Proteins

Biomolecular condensates are complex fluids formed by liquid-liquid phase separation of macromolecules. Similar to other types of soft matter, they feature a range of biophysical properties that distinguish them from the cellular milieu. As a separate phase, they have an identifiable interface that dictates their interaction with the cytoplasm and other membraneless organelles. In this work, we engineer the interface of condensates to build novel hierarchical mesoscale structures from two immiscible disordered proteins: the RGG domain of LAF-1, a RNA-processing protein involved in germ granule assembly and the low complexity domain (LC) of FUS, an RNA binding protein whose aggregation is implicated in age-related neurodegeneration. RGG and FUS LC do not co-partition with one another and instead form discrete protein-rich condensed phases. Despite their apparent immiscibility, we identified conditions that can promote hierarchical assembly, either kinetically trapping one phase in the other, or using a designer surfactant protein that reduces the interfacial tension between the two phases. In addition, we studied factors that impact condensate miscibility and structure formation, including surface properties and viscoelasticity. This study probes the principles that underlie formation and assembly of complex structures from biomolecular condensates and provides a strategy for designing synthetic multiphasic materials capable of spatial partitioning.

biophysics↗

Astrocyte-specific secretome profiling reveals its correlation with neurological disorders

Secreted proteins mediate intercellular communication throughout the lives of multicellular organisms. However, due to the lack of new technology for secreted protein capturing, the progress of "secretomics lags behind. Here, we report a two-step secretome enrichment method (tsSEM) combining unnatural amino acid labeling and click chemistry-based biorthogonal reaction, which enables in vitro secretome profiling in the presence of serum. Using this novel method, we systematically investigated the secretome of human iPSCs-derived astrocytes (iAst) in different disease models and identified a panel of astrocyte-secreted proteins that are responsible for its non-cell autonomous toxicity under disease conditions. Furthermore, we validated two astrocytes-derived novel neurotrophic proteins, FAM3C and KITLG, which we identified from disease models, and found that they could boost neurite outgrowth, protect neurons, and promote neural progenitor proliferation. Our study highlights the utility of secretome profiling of iAst and demonstrates its applications in disease study and target identification and validation in drug development.

neuroscience↗

Integrated temporal profiling of iPSCs-derived motor neurons from ALS patients carrying C9orf72, FUS, TARDBP, and SOD1 mutations

Amyotrophic Lateral Sclerosis (ALS) is a lethal neurodegenerative disease that damages motor neurons in the central nervous system, causing progressive muscle weakness that ultimately leads to death. However, its underlying mechanisms still need to be fully understood, particularly the heterogeneity and similarity between various gene mutants during disease progression. In this study, we conducted temporal RNA-seq profiling in human induced pluripotent stem cells (hiPSCs) and iPSC-derived motor neurons (iMNs) carrying the C9orf72, FUS, TARDBP, and SOD1 mutations from both ALS patients and healthy individuals. We discovered dysregulated gene expression and alternative splicing (AS) throughout iMN development and maturation, and ALS iMNs display enrichment of cytoskeletal defects and synaptic alterations from premature stage to mature iMNs. Our findings indicate that synaptic gene dysfunction is the common molecular hallmark of fALS, which might result in neuronal susceptibility and progressive motor neuron degeneration. Analysis of upstream splicing factors revealed that differentially expressed RNA-binding proteins (RBPs) in ALS iMNs may cause abnormal AS events, suggesting the importance of studying RBP defects in ALS research. Overall, our research provides a comprehensive and valuable resource for gaining insights into the shared mechanisms of ALS pathogenesis during motor neuron development and maturation in iMN models.

neuroscience↗

Neu5Gc binding loss of subtype H7 influenza A virus facilitates adaptation to gallinaceous poultry following transmission from waterbirds but restricts spillback

Migratory waterfowl, gulls, and shorebirds serve as natural reservoirs for influenza A viruses, with potential spillovers to domestic poultry and humans. The intricacies of interspecies adaptation among avian species, particularly from wild birds to domestic poultry, are not fully elucidated. In this study, we investigated the molecular mechanisms underlying avian species barriers in H7 transmission, particularly the factors responsible for the disproportionate distribution of poultry infected with A/Anhui/1/2013 (AH/13)-lineage H7N9 viruses. We hypothesized that the differential expression of N-glycolylneuraminic acid (Neu5Gc) among avian species exerts selective pressure on H7 viruses, shaping their evolution and enabling them to replicate and transmit efficiently among gallinaceous poultry, particularly chickens. Our glycan microarray and biolayer interferometry experiments showed that AH/13-lineage H7N9 viruses exclusively bind to Neu5Ac, in contrast to wild waterbird H7 viruses that bind both Neu5Ac and Neu5Gc. Significantly, reverting the V179 amino acid in AH/13-lineage back to the I179, predominantly found in wild waterbirds, expanded the binding affinity of AH/13-lineage H7 viruses from exclusively Neu5Ac to both Neu5Ac and Neu5Gc. When cultivating H7 viruses in cell lines with varied Neu5Gc levels, we observed that Neu5Gc expression impairs the replication of Neu5Ac-specific H7 viruses and facilitates adaptive mutations. Conversely, Neu5Gc deficiency triggers adaptive changes in H7 viruses capable of binding to both Neu5Ac and Neu5Gc. Additionally, we assessed Neu5Gc expression in the respiratory and gastrointestinal tissues of seven avian species, including chickens, Canada geese, and various dabbling ducks. Neu5Gc was absent in chicken and Canada goose, but its expression varied in the duck species. In summary, our findings reveal the crucial role of Neu5Gc in shaping the host range and interspecies transmission of H7 viruses. This understanding of virus-host interactions is crucial for developing strategies to manage and prevent influenza virus outbreaks in diverse avian populations. Author SummaryMigratory waterfowl, gulls, and shorebirds are natural reservoirs for influenza A viruses that can occasionally spill over to domestic poultry, and ultimately humans. The molecular mechanisms underlying interspecies transmission and adaptation, particularly between wild birds and domestic poultry, remain poorly understood. This study showed wild-type H7 influenza A viruses from waterbirds initially bind to glycan receptors terminated with N-Acetylneuraminic acid (Neu5Ac) or N-Glycolylneuraminic acid (Neu5Gc). However, after enzootic transmission in chickens, the viruses exclusively bind to Neu5Ac. The absence of Neu5Gc expression in gallinaceous poultry, particularly chickens, exerts selective pressure, shaping influenza virus populations, and promoting the acquisition of adaptive amino acid substitutions in the hemagglutinin protein of H7 influenza A viruses. This results in the loss of Neu5Gc binding and an increase in virus transmissibility in gallinaceous poultry, particularly chickens. Consequently, the transmission capability of these poultry-adapted H7 viruses in wild water birds decreases. Timely intervention, such as stamping out, may help reduce virus adaptation to domestic chicken populations and lower the risk of enzootic outbreaks, including those caused by influenza A viruses exhibiting high pathogenicity.

microbiology↗

Engineered Bacillus subtilis as oral probiotics to target circulating lactic acid

Elevated lactate concentrations are implicated in various acute and chronic diseases such as sepsis and mitochondrial dysfunction, respectively. Conversely, ineffective lactate clearance is associated with poor clinical prognoses and high mortality in these diseases. While several groups have proposed using small molecule inhibitors and enzyme replacement to reduce circulating lactate, there are few practical and effective ways to manage this condition. Recent evidence suggests that lactate is exchanged between systemic circulation and the gut, allowing bidirectional modulation between the gut microbiota and peripheral tissues. Inspired by these findings, this work seeks to engineer spore-forming probiotic B. subtilis strains to enable intestinal delivery of lactate oxidase as a therapeutic enzyme. After strain optimization, we showed that oral administration of engineered B. subtilis spores to the gut of mice reduced elevations in blood lactate in two different mouse models involving exogenous challenge or pharmacologic perturbation without disrupting gut microbiota composition, liver function, or immune homeostasis. Taken together, through the oral delivery of engineered probiotic spores to the gastrointestinal tract, our proof-of-concept study offers a practical strategy to aid in the management of disease states with elevated blood lactate and provides a new approach to knocking down circulating metabolites to help understand their roles in host physiological and pathological processes. Significance StatementThis study pioneers the use of engineered Bacillus subtilis spores as an oral probiotic therapy to enhance the clearance of elevated blood lactate, a condition linked to severe health issues like sepsis and metabolic disorders. By genetically modifying these spores to deliver therapeutic enzymes directly to the gut, we demonstrated a practical, effective method to modulate systemic lactate levels. This approach leverages the natural exchange between the gut microbiota and systemic circulation, offering a new strategy for managing diseases associated with lactate dysregulation. The safety and efficacy of this method were validated in mouse models, providing a foundation for future clinical applications.

bioengineering↗

Distinct functions of EHMT1 and EHMT2 in cancer chemotherapy and immunotherapy

EHTM1 (GLP) and EHMT2 (G9a) are closely related protein lysine methyltransferases often thought to function together as a heterodimer to methylate histone H3 and non-histone substrates in diverse cellular processes including transcriptional regulation, genome methylation, and DNA repair. Here we show that EHMT1/2 inhibitors cause ATM-mediated slowdown of replication fork progression, accumulation of single-stranded replication gaps, emergence of cytosolic DNA, and increased expression of STING. EHMT1/2 inhibition strongly potentiates the efficacy of alkylating chemotherapy and anti-PD-1 immunotherapy in mouse models of tripe negative breast cancer. The effects on DNA replication and alkylating agent sensitivity are largely caused by the loss of EHMT1-mediated methylation of LIG1, whereas the elevated STING expression and remarkable response to immunotherapy appear mainly elicited by the loss of EHMT2 activity. Depletion of UHRF1, a protein known to be associated with EHMT1/2 and LIG1, also induces STING expression, and depletion of either EHMT2 or UHRF1 leads to demethylation of specific CpG sites in the STING1 promoter, suggestive of a distinct EHMT2-UHRF1 axis that regulates DNA methylation and gene transcription. These results highlight distinct functions of the two EHMT paralogs and provide enlightening paradigms and corresponding molecular basis for combination therapies involving alkylating agents and immune checkpoint inhibitors.

cancer biology↗

Targeting adipocyte ESRRA promotes osteogenesis and vascular formation in adipocyte-rich bone marrow

Ectopic bone marrow adipocytes (BMAds) accumulation occurring under diverse pathophysiological conditions leads to bone deterioration. Estrogen-related receptor (ESRRA) is a key regulator responding to metabolic stress. Here, we show that adipocyte-specific ESRRA deficiency rescues osteogenesis and vascular formation in adipocyte-rich bone marrow due to estrogen deficiency or obesity. Mechanistically, adipocyte ESRRA interferes with E2/ESR1 signaling resulting in transcriptional repression of secreted phosphoprotein 1 (Spp1); and positively modulates Leptin expression by binding to its promoter. ESRRA abrogation results in enhanced SPP1 and decreased LEPTIN secretion from both visceral adipocytes and BMAds, concertedly dictating bone marrow stromal stem cell fate commitment and restoring type H vessel formation, constituting a feed-forward loop for bone formation. Pharmacological inhibition of ESRRA protects obese mice against bone loss and high marrow adiposity. Thus, our findings highlight a therapeutic approach via targeting adipocyte ESRRA to preserve bone formation especially in detrimental adipocyte-rich bone milieu. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/552932v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@1132da3org.highwire.dtl.DTLVardef@19342aorg.highwire.dtl.DTLVardef@afe8d7org.highwire.dtl.DTLVardef@dfb1f9_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Grand Biological Universe: Genome space geometry unravels looking for a single metric is likely to be futile in evolution

Understanding the differences between genomic sequences of different lives is crucial for biological classification and phylogeny. Here, we downloaded all the reliable sequences of the seven kingdoms and determined the dimensions of the genome space embedded in the Euclidean space, along with the corresponding Natural Metrics. The concept of the Grand Biological Universe is further proposed. In the grand universe, the convex hulls formed by the universes of seven kingdoms are mutually disjoint, and the convex hulls formed by different biological groups within each kingdom are mutually disjoint. This study provides a novel geometric perspective for studying molecular biology and also offers an accurate way for large-scale sequence comparison in a real-time manner. Most importantly, this study shows that, due to the space-time distortion in the biological genome space similar to Einsteins theory, it is futile to look for a single metric to measure different biological universes, as previous studies have done.

evolutionary biology↗