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Biology subjects

Su, Y.

Publications and source records attributed to Su, Y..

At least 127 records · Page 7Linked to original sources

Structure-guided inhibition of the cancer DNA-mutating enzyme APOBEC3A

The normally antiviral enzyme APOBEC3A1-4 is an endogenous mutagen in many different human cancers5-7, where it becomes hijacked to fuel tumor evolvability. APOBEC3As single-stranded DNA C-to-U editing activity1, 8 results in multiple mutagenic outcomes including signature single-base substitution mutations (isolated and clustered), DNA breakage, and larger-scale chromosomal aberrations5-7. Transgenic expression in mice demonstrates its tumorigenic potential9. APOBEC3A inhibitors may therefore comprise a novel class of anticancer agents that work by blocking mutagenesis, preventing tumor evolvability, and lessening detrimental outcomes such as drug resistance and metastasis. Here we reveal the structural basis of competitive inhibition of wildtype APOBEC3A by hairpin DNA bearing 2-deoxy-5-fluorozebularine in place of the cytidine in the TC recognition motif that is part of a three-nucleotide loop. The nuclease-resistant phosphorothioated derivatives of these inhibitors maintain nanomolar in vitro potency against APOBEC3A, localize to the cell nucleus, and block APOBEC3A activity in human cells. These results combine to suggest roles for these inhibitors to study A3A activity in living cells, potentially as conjuvants, leading toward next-generation, combinatorial anti-mutator and anti-cancer therapies.

cancer biology↗

Brainstem Dbh+ Neurons Control Chronic Allergen-Induced Airway Hyperreactivity

Chronic exposure of the lung to irritants such as allergen is a primary cause of asthma characterized by exaggerated airway constriction, also called hyperreactivity, which can be life-threatening. Aside from immune cells, vagal sensory neurons are important for airway hyperreactivity 1-4. However, the identity and signature of the downstream nodes of this adaptive circuit remains poorly understood. Here we show that a single population of Dbh+neurons in the nucleus of the solitary tract (nTS) of the brainstem, and downstream neurons in the nucleus ambiguous (NA), are both necessary and sufficient for chronic allergen-induced airway hyperreactivity. We found that repeated exposures of mice to inhaled allergen activates nTS neurons in a mast cell-, interleukin 4 (IL-4)-and vagal nerve-dependent manner. Single-nucleus RNA-seq of the nTS at baseline and following allergen challenges reveals that a Dbh+ population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted, while chemogenetic activation promoted hyperreactivity. Viral tracing indicates that Dbh+nTS neurons, capable of producing norepinephrine, project to the NA, and NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that then directly drive airway constriction. Focusing on transmitters, delivery of norepinephrine antagonists to the NA blunted allergen-induced hyperreactivity. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. The knowledge opens the possibility of targeted neural modulation as an approach to control refractory allergen-induced airway constriction.

cell biology↗

Benchmarking Algorithms for Gene Set Scoring of Single-cell ATAC-seq Data

Gene set scoring (GSS) has been routinely conducted for gene expression analysis of bulk or single-cell RNA-seq data, which helps to decipher single-cell heterogeneity and cell-type-specific variability by incorporating prior knowledge from functional gene sets. Single-cell assay for transposase accessible chromatin using sequencing (scATAC-seq) is a powerful technique for interrogating single-cell chromatin-based gene regulation, and genes or gene sets with dynamic regulatory potentials can be regarded as cell-type specific markers as if in scRNA-seq. However, there are few GSS tools specifically designed for scATAC-seq, and the applicability and performance of RNA-seq GSS tools on scATAC-seq data remain to be investigated. We systematically benchmarked ten GSS tools, including four bulk RNA-seq tools, five single-cell RNA-seq (scRNA-seq) tools, and one scATAC-seq method. First, using matched scATAC-seq and scRNA-seq datasets, we find that the performance of GSS tools on scATAC-seq data is comparable to that on scRNA-seq, suggesting their applicability to scATAC-seq. Then the performance of different GSS tools were extensively evaluated using up to ten scATAC-seq datasets. Moreover, we evaluated the impact of gene activity conversion, dropout imputation, and gene set collections on the results of GSS. Results show that dropout imputation can significantly promote the performance of almost all GSS tools, while the impact of gene activity conversion methods or gene set collections on GSS performance is more GSS tool or dataset dependent. Finally, we provided practical guidelines for choosing appropriate pre-processing methods and GSS tools in different scenarios.

bioinformatics↗

Kinase-modulated bioluminescent indicators enable noninvasive imaging of drug activity in the brain

Aberrant kinase activity contributes to the pathogenesis of brain cancers, neurodegeneration, and neuropsychiatric diseases, but identifying kinase inhibitors that function in the brain is challenging. Drug levels in blood do not predict efficacy in the brain because the blood-brain barrier prevents entry of most compounds. Rather, assessing kinase inhibition in the brain requires tissue dissection and biochemical analysis, a time-consuming and resource-intensive process. Here, we report kinase-modulated bioluminescent indicators (KiMBIs) for non-invasive longitudinal imaging of drug activity in the brain based on a recently optimized luciferase-luciferin system. We develop an ERK KiMBI to report inhibitors of the Ras-Raf-MEK-ERK pathway, for which no bioluminescent indicators previously existed. ERK KiMBI discriminates between brain-penetrant and non-penetrant MEK inhibitors, reveals blood-tumor barrier leakiness in xenograft models, and reports MEK inhibitor pharmacodynamics in native brain tissues and intracranial xenografts. Finally, we use ERK KiMBI to screen ERK inhibitors for brain efficacy, identifying temuterkib as a promising brain-active ERK inhibitor, a result not predicted from chemical characteristics alone. Thus, KiMBIs enable the rapid identification and pharmacodynamic characterization of kinase inhibitors suitable for treating brain diseases.

pharmacology and toxicology↗

Emerging variants of SARS-CoV-2 NSP10 highlight strong functional conservation of its binding to two non-structural proteins, NSP14 and NSP16

The coronavirus SARS-CoV-2 protects its RNA from being recognized by host immune responses by methylation of its 5 end, also known as capping. This process is carried out by two enzymes, non-structural protein 16 (NSP16) containing 2-O-methyltransferase and NSP14 through its N7 methyltransferase activity, which are essential for the replication of the viral genome as well as evading the hosts innate immunity. NSP10 acts as a crucial cofactor and stimulator of NSP14 and NSP16. To further understand the role of NSP10, we carried out a comprehensive analysis of >13 million globally collected whole-genome sequences (WGS) of SARS-CoV-2 obtained from the Global Initiative Sharing All Influenza Data (GISAID) and compared it with the reference genome Wuhan/WIV04/2019 to identify all currently known variants in NSP10. T12I, T102I, and A104V in NSP10 have been identified as the three most frequent variants and characterized using X-ray crystallography, biophysical assays and enhanced sampling simulations. In contrast to other proteins such as spike and NSP6, NSP10 is significantly less prone to mutation due to its crucial role in replication. The functional effects of the variants were examined for their impact on the binding affinity and stability of both NSP14-NSP10 and NSP16-NSP10 complexes. These results highlight the limited changes induced by variant evolution in NSP10 and reflect on the critical roles NSP10 plays during the SARS-CoV-2 life cycle. These results also indicate that there is limited capacity for the virus to overcome inhibitors targeting NSP10 via the generation of variants in inhibitor binding pockets. Significance StatementThe SARS-CoV-2 proteins have constantly been evolving. These variants assist the virus to survive, adapt and evade the host immune responses. While the main focus has been on structural proteins like Spike, there is very limited structural and functional information on the effects of emerging mutations on other essential non-structural viral proteins. One such protein is NSP10, an essential cofactor for NSP14 and NSP16. This study demonstrates that NSP10 is more resistant to genetic variations than other SARS-CoV-2 non-structural proteins and that the presence of mutations conserve structural and dynamic changes in NSP10. The effects of naturally occurring mutations reflect the evolutionary relationship between structurally conserved essential cofactors, their function and the role they play in the survival of the virus.

biophysics↗

New high-resolution maps show that rubber causes significant deforestation

Understanding the impacts of cash crop expansion on natural forest is of fundamental importance. However, for most crops there are no remotely-sensed global maps1, and global deforestation impacts are estimated using models and extrapolations. Natural rubber is an example of a major commodity for which deforestation impacts have been highly uncertain, with estimates differing more than five-fold1-4. Here we harnessed earth observation satellite data and cloud computing5 to produce the first high-resolution maps of rubber and associated deforestation covering all Southeast Asia. Our maps indicate that rubber-related forest loss has been significantly underestimated in policy, by the public and in recent reports6-8. Our direct remotely-sensed observations show that deforestation for rubber is two to threefold higher than suggested by figures currently widely used for setting policy4. With over 3.76 million hectares of forest loss for rubber since 1993 (2.77 [2.5-3 95% CI] million hectares since 2000), and over 1 million hectares of rubber plantations established in Key Biodiversity Areas, the impacts of rubber on biodiversity and ecosystem services in Southeast Asia are extensive. Thus, rubber deserves more attention in domestic policy, within trade agreements and in incoming due diligence regulations.

ecology↗

Label-free cleared tissue microscopy and machine learning for 3D histopathology of biomaterial implants

Tissue clearing of whole intact organs has enhanced imaging by enabling the exploration of tissue structure at a subcellular level in three-dimensional space. Although clearing and imaging of the whole organ have been used to study tissue biology, the microenvironment in which cells evolve to adapt to biomaterial implants or allografts in the body is poorly understood. Obtaining high-resolution information from complex cell-biomaterial interactions with volumetric landscapes represents a key challenge in the fields of biomaterials and regenerative medicine. To provide a new approach to examine how tissue responds to biomaterial implants, we apply cleared tissue light-sheet microscopy and three-dimensional reconstruction to utilize the wealth of autofluorescence information for visualizing and contrasting anatomical structures. This study demonstrates the adaptability of the clearing and imaging technique to provide sub-cellular resolution (0.6m isotropic) 3D maps of various tissue types, using samples from fully intact peritoneal organs to volumetric muscle loss injury specimens, with and without biomaterials implants. We further apply computational-driven image classification to analyze the autofluorescence spectrum at multiple emission wavelengths to categorize tissue types in the tissue-biomaterial microenvironment.

bioengineering↗

An image cryptography method in highly error-prone DNA storage channel

Rapid development in synthetic technologies has boosted DNA as a potential medium for large-scale data storage. Meanwhile, how to implement data security in DNA storage system is still an unsolved problem. In this paper, we propose an image encryption method based on the modulation-based storage architecture. The key idea is to take advantage of the unpredictable modulation signals to encrypt image in highly error-prone DNA storage channel. Numerical results demonstrate that our image encryption method is feasible and effective with excellent security against various attacks (statistical, differential, noise and data loss, etc.). Compared with other methods by DNA molecules hybridization reaction, the proposed method is more reliable and feasible for large-scale applications.

synthetic biology↗

CD46 targeted 212Pb alpha particle radioimmunotherapy for prostate cancer treatment

We recently identified CD46 as a novel prostate cancer cell surface antigen that shows lineage independent expression in both adenocarcinoma and small cell neuroendocrine subtypes of metastatic castration resistant prostate cancer (mCRPC), discovered an internalizing human monoclonal antibody YS5 that binds to a tumor selective CD46 epitope, and developed a microtubule inhibitor-based antibody drug conjugate that is in a multi-center phase I trial for mCRPC (NCT03575819). Here we report the development of a novel CD46-targeted alpha therapy based on YS5. We conjugated 212Pb, an in vivo generator of alpha-emitting 212Bi and 212Po, to YS5 through the chelator TCMC to create the radioimmunoconjugate, 212Pb-TCMC-YS5. We characterized 212Pb-TCMC-YS5 in vitro and established a safe dose in vivo. We next studied therapeutic efficacy of a single dose of 212Pb-TCMC-YS5 using three prostate cancer small animal models: a subcutaneous mCRPC cell line-derived xenograft (CDX) model (subcu-CDX), an orthotopically grafted mCRPC CDX model (ortho-CDX), and a prostate cancer patient-derived xenograft model (PDX). In all three models, a single dose of 20 Ci 212Pb-TCMC-YS5 was well tolerated and caused potent and sustained inhibition of established tumors, with significant increases of survival in treated animals. A lower dose (10 Ci 212Pb-TCMC-YS5) was also studied on the PDX model, which also showed a significant effect on tumor growth inhibition and prolongation of animal survival. These results demonstrate that 212Pb-TCMC-YS5 has an excellent therapeutic window in preclinical models including PDXs, opening a direct path for clinical translation of this novel CD46-targeted alpha radioimmunotherapy for mCRPC treatment. SignificanceThis study reports a novel CD46 targeted 212Pb alpha particle radioimmunotherapy, 212Pb-TCMC-YS5, that is well tolerated and shows potent anti-tumor activity (tumor growth inhibition and increase of animal survival) in vivo in three prostate cancer small animal models, i.e., a subcutaneous and an intraprostate orthotopic mCRPC cell line-derived xenograft models, and a prostate cancer patient-derived xenograft model. Given that YS5 is a clinical stage human antibody, this YS5-based 212Pb alpha particle therapy has potential of translation to the clinic for treatment of mCRPC patients.

bioengineering↗

Treatment of prostate cancer with CD46 targeted 225Ac alpha particle radioimmunotherapy

Radiopharmaceutical therapy is changing the standard of care in prostate cancer (PCa) and other malignancies. We previously reported high CD46 expression in PCa and developed an antibody-drug conjugate and immunoPET agent based on the YS5 antibody, which targets a tumor-selective CD46 epitope. Here, we present the preparation, preclinical efficacy, and toxicity evaluation of [225Ac]DOTA-YS5, a radioimmunotherapy agent based on the YS5 antibody. Our radiolabeled antibody retains binding efficacy and shows a high tumor to background ratio in PCa xenografts. Furthermore, we show that radiolabeled antibody was able to suppress the growth of cell-derived and patient-derived xenografts, including PSMA-positive and deficient models. Nephrotoxicity, not seen at low radioactive doses, is evident at higher radioactivity dose levels, likely due to redistribution of daughter isotope 213Bi. Overall, this preclinical study confirms that [225Ac]DOTA-YS5 is a highly effective treatment and suggests feasibility for clinical translation of CD46 targeted radioligand therapy in PCa.

cancer biology↗

A non-ligand surrogate agonist antibody that enhances canonical Wnt signaling and bone regeneration

The Wnt signaling pathway promotes tissue regeneration and is a promising therapeutic target for treatment of osteolytic bone diseases. Here we report the discovery of a novel type of canonical Wnt agonist antibody that does not operate as a ligand surrogate. The antibody increases Wnt/{beta}-catenin signaling with or without exogenously provided Wnt ligands. It binds to a site on the P3 domain of LRP6 that is distinct from where the Wnt3a ligand and the DKK1 antagonist bind. The agonist effect persists in the presence of DKK1 and is further amplified by R-spondin even when Wnt ligands are not provided, suggesting a potential use for this antibody in ligand-low or insufficient settings. The antibody induces osteoblastic differentiation and mineralization in vitro and restores bone loss in vivo in a myeloma-derived intrafemoral mouse model, opening a potential path for therapeutic development in osteolytic diseases caused by cancer and aging.

bioengineering↗

Toxicity of microplastics and plastic additive co-exposure in liver Disse organoids from healthy donors and patient-derived induced pluripotent stem cells

The ubiquitous microplastics (MPs) and plastic additives in the environment usually form complexes, enter human blood circulation, and increase the risk of steatohepatitis. The liver Disse space plays a vital role in corresponding hepatic pathological processes. However, due to the limited understanding of the regulatory cues in multilineage maturation, the generation of large-scale Disse-like organoids (DOs) mirroring the comprehensive toxicity responses of MPs is challenging. Here, using human-induced pluripotent stem cells (hiPSCs), we biofabricated healthy donors and patient-derived DOs containing hepatocytes, endothelial cells, and hepatic stellate cells, resembling the features of Disse space. These organoids revealed that polystyrene MPs preferentially entered endothelial cells and then dispersed throughout the organoids, similar to reported studies in zebrafish. Co-exposure to MPs and tetrabromobisphenol A (TBBPA), a common plastic additive, showed enhanced accumulation of contamination in the organoids. We also biofabricated alcoholic liver disease (ALD) patient-derived DOs representing the specific disease transcriptional profiles. We found that co-exposure to MPs and TBBPA at environmental-related dosages significantly elevated the pathological transcriptional expression and biochemical profiles in patient-derived DOs but not in healthy organoids, suggesting that both hereditary factors and pollutants contribute to susceptibility to environmental toxicants. This study exemplified the value of biofabricated hiPSC-derived organoids in environmental toxicology and offered a powerful strategy for personalized toxicology evaluation.

bioengineering↗

lincRNA RP24-315D19.10 promotes endometrialdecidualization via upregulation of hnRNPA2B1

Sufficient decidualization is necessary to maintain successful pregnancy. The physiological function and underlying molecular mechanisms of intergenic long non-coding RNA (lincRNAs) in this process remain largely unknown. Herein, we identified a lincRNA, RP24-315D19.10, which is highly expressed during mouse decidualization during early pregnancy, by performing RNA-sequencing (RNA-seq) analysis and weighted gene co-expression network analysis (WGCNA). Detailed cell and molecular assays revealed that lincRNA RP24-315D19.10 knockdown blocked decidualization in primary mouse endometrial stromal cells (mESCs), suggesting that RP24-315D19.10 is a promoting factor for decidualization. Mechanistically, cytoplasmic RP24-315D19.10 directly interacted with heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) and upregulated its protein level. Moreover, we found that hnRNPA2B1 is involved in the regulation of decidualization through loss- and gain-of-function studies in vitro. Clinically, patients diagnosed with spontaneous miscarriage were found to have lower hnRNPA2B1 levels than healthy individuals, suggesting that RP24-315D19.10-regulated hnRNPA2B1 may participate in the development and progression of early spontaneous abortion. Our study indicates that RP24-315D19.10 enhances endometrial decidualization in a hnRNPA2B1-dependent manner, providing further insights into this physiological process.

molecular biology↗

Swim bladder resonance enhances hearing in crucian carp (Carassius auratus)

Sound sensing is vital for fish and more effort is necessary to address the hearing mechanism in fish. Here, we performed auditory evoked potentials (AEP) measurement, micro-computed tomography (Micro-CT) scanning, and numerical simulation to investigate the resonance of swim bladder and its influence on auditory sensitivity in crucian carp (Carassius auratus). The AEP results showed that at the tested frequency range up to 1000 Hz, the mean auditory thresholds of control fishes with an intact swim bladder were lower than that of treated fishes with a deflated swim bladder by 0.38-30.52 dB re 1 Pa. At the high frequency end, control fishes had a high but measurable auditory threshold. Correspondingly, numerical simulations showed that the intact swim bladder had a mean resonance frequency of 826{+/-}13.6 Hz, ranging from 810 to 840 Hz while the deflated swim bladder had no predominant resonance peak below 1000 Hz. The amplitude of received sound pressure at the resonance frequency for a sample in control group was 34.3 dB re 1 Pa higher than that for a treated sample, and the acceleration at the asteriscus of the control fish was higher than the treat fish by 43.13 dB re 1 m s-2. Both AEP experiment and modeling results showed that hearing sensitivity is enhanced through resonance of swim bladder in crucian carp and provided additional understandings on hearing mechanism in fish. Summary statementWe used AEP measurement, Micro-CT scanning, and numerical simulation to demonstrate that the resonance of swim bladder can enhance hearing in crucian carp.

animal behavior and cognition↗

Three-dimensional structured illumination microscopy with enhanced axial resolution

We present two distinct, complementary methods for improving axial resolution in three-dimensional structured illumination microscopy (3D SIM) with minimal or no modification to the optical system. First, we show that placing a mirror directly opposite the sample enables 4-beam interference with higher spatial frequency content than 3D SIM illumination, offering near-isotropic imaging with [~]120 nm lateral and 160 nm axial resolution. Second, we develop an improved deep learning method that can be directly applied to 3D SIM data, obviating the need for additional hardware. This procedure results in [~]120 nm isotropic resolution and can be combined with denoising to facilitate volumetric imaging spanning dozens of time points. We demonstrate the potential of these advances by imaging a variety of cellular samples, delineating the nanoscale distribution of vimentin and microtubule filaments, observing the relative positions of caveolar coat proteins and lysosomal markers, and visualizing rich cytoskeletal dynamics within T-cells in the early stages of immune synapse formation.

cell biology↗

Antigen-Specific Antibody Design and Optimization with Diffusion-Based Generative Models

Antibodies are immune system proteins that protect the host by binding to specific antigens such as viruses and bacteria. The binding between antibodies and antigens is mainly determined by the complementarity-determining regions (CDR) of the antibodies. In this work, we develop a deep generative model that jointly models sequences and structures of CDRs based on diffusion probabilistic models and equivariant neural networks. Our method is the first deep learning-based method that generates antibodies explicitly targeting specific antigen structures and is one of the earliest diffusion probabilistic models for protein structures. The model is a "Swiss Army Knife" capable of sequence-structure co-design, sequence design for given backbone structures, and antibody optimization. We conduct extensive experiments to evaluate the quality of both sequences and structures of designed antibodies. We find that our model could yield competitive results in binding affinity measured by biophysical energy functions and other protein design metrics.

bioinformatics↗

Basal forebrain cholinergic circuits orchestrate diverse cell types in the adult dentate gyrus to support neural stem cell function and spatial memory

Dentate gyrus (DG) is a critical structure involved in spatial memory and adult neurogenesis, two distinct processes dynamically regulated by local circuits comprising diverse populations of DG cells. It remains unknown how these DG cells are orchestrated to regulate these distinct hippocampal functions. Here we report activation of a cholinergic circuit from the Diagonal Band of Broca to DG promotes quiescent radial neural stem cell (rNSC) activation and spatial memory. Furthermore, single-nucleus RNA-sequencing reveals broad transcriptomic changes across DG mature and adult-born cells in response to cholinergic-circuit activation. Notably, neuronal populations exhibit cholinergic-activity-induced molecular changes related to synaptic functions crucial for spatial memory; while rNSCs exhibit changes related to structural remodeling and neurogenic proliferation crucial for hippocampal neurogenesis. Electrophysiology and NicheNet analyses reveal granule cells, endothelial cells, and astrocytes as potential intermediaries for cholinergic regulation of rNSCs. Our findings reveal cell-type-specific signaling mechanisms underlying cholinergic regulation of distinct DG functions.

neuroscience↗

Integrative multi-omics analysis reveals molecular subtypes and tumor evolution of synovial sarcoma

Synovial sarcomas (SS) are malignant mesenchymal tumors characterized by the SS18-SSX fusion gene, which drives tumorigenesis by altering the composition of the BAF complex. Secondary genomic alterations that determine variations in tumor phenotype or clinical presentation are largely unknown. Herein, we present transcriptome, targeted DNA-sequencing, and proteomics analysis of 91 synovial sarcomas from 55 patients. We identified three SS clusters (SSCs) characterized by distinct histology, tumor microenvironments, genomic complexities, therapeutic effects, and clinical outcomes. Eight BAF complex components are differentially expressed among SSCs, and their role in mesenchymal-epithelial-transition is supported by single cell sequencing. The epithelial cells of biphasic tumors are more susceptible to developing copy number alterations, including amplification of PDCD1 and TMPRSS2. Our findings explain broad concepts in SS biology and imply that the BAF composition at the start of the tumorigenesis (i.e. the cellular linage) may determine the SS subtype, providing a rationale for individualized treatment strategies.

cancer biology↗