Systems Biology
Structural basis for translation inhibition by MERS-CoV Nsp1 reveals a conserved mechanism for betacoronaviruses
Cell Rep. 2023 Sep 19;42(10):113156. doi: 10.1016/j.celrep.2023.113156. Online ahead of print.
ABSTRACT
All betacoronaviruses (β-CoVs) encode non-structural protein 1 (Nsp1), an essential pathogenicity factor that potently restricts host gene expression. Among the β-CoV family, MERS-CoV is the most distantly related member to SARS-CoV-2, and the mechanism for host translation inhibition by MERS-CoV Nsp1 remains controversial. Herein, we show that MERS-CoV Nsp1 directly interacts with the 40S ribosomal subunit. Using cryogenic electron microscopy (cryo-EM), we report a 2.6-Å structure of the MERS-CoV Nsp1 bound to the human 40S ribosomal subunit. The extensive interactions between C-terminal domain of MERS-CoV Nsp1 and the mRNA entry channel of the 40S ribosomal subunit are critical for its translation inhibition function. This mechanism of MERS-CoV Nsp1 is strikingly similar to SARS-CoV and SARS-CoV-2 Nsp1, despite modest sequence conservation. Our results reveal that the mechanism of host translation inhibition is conserved across β-CoVs and highlight a potential therapeutic target for the development of antivirals that broadly restrict β-CoVs.
PMID:37733586 | DOI:10.1016/j.celrep.2023.113156
Genetic diversity and characterization of rhinoviruses from Chinese clinical samples with a global perspective
Microbiol Spectr. 2023 Sep 21:e0084023. doi: 10.1128/spectrum.00840-23. Online ahead of print.
ABSTRACT
Rhinovirus (RV) is a significant pathogen causing upper and lower respiratory diseases and is one of the most prevalent human respiratory viruses. However, research on the genetic diversity and evolutionary dynamics of RVs in China and worldwide remains limited. To address this knowledge gap, we utilized Chinese clinical RV samples as a starting point and detected and reported 22 types, including A9, B3, and C13, in China for the first time. Among these, A67, A76, and A106 were also detected and reported in Asia for the first time, characterizing their genetic diversity. We also identified A110 as a novel type of RVA and reported its distinctive characteristics in phylogeny, secondary structure, and capsid protein structure. Furthermore, by mining, refining, and annotating RV sequence data available worldwide, four previously unreported novel types, B107, C58, C59, and C60, were identified, and their genetic diversity was revealed. Furthermore, we observed variations in the guanine-cytosine (GC) content among different serotypes and clades. Also of note was that, based on a complete and refined VP1 data set, the evolutionary dynamics of RV were analyzed systematically and on a large scale for the first time. IMPORTANCE Based on clinical samples collected in China, we detected and reported 22 types for the first time in China, as well as three types for the first time in Asia, and reported their genetic characteristics and diversity. We identified a novel type of Rhinovirus (RV), A110, highlighting its unique genetic features. We annotated the genomic structure and serotype of all the existing RV sequences in the database, and four novel RV types were identified and their genetic diversity reported. Combined with the sequence annotation, we constructed a complete VP1 data set of RV and conducted the first large-scale evolutionary dynamics analysis of RV. Based on a high-quality data set, we conducted a comprehensive analysis of the guanine-cytosine (GC) content variations among serotypes of RVs. This study provides crucial theoretical support and valuable data for understanding RV's genetic diversity and developing antiviral strategies.
PMID:37733296 | DOI:10.1128/spectrum.00840-23
Polarized contact behavior in directionally migrating <em>Xenopus</em> gastrula mesendoderm
Int J Dev Biol. 2023 Sep 18. doi: 10.1387/ijdb.230123rw. Online ahead of print.
ABSTRACT
The control of cell-cell adhesion and detachment is essential for collective migration and cell rearrangement. Here, we have used the contact behavior of Xenopus gastrula mesoderm explants migrating directionally on ectoderm conditioned substratum to study the regulation of active cell-cell detachment. When colliding laterally, explants repelled each other, whereas they fused front-to-back when aligned in the direction of migration. For this mesoderm polarization by the substratum, we identified three control modules. First, PDGF-A signaling normally suppresses contact-induced collapse of lamellipodia in a polarized manner. Disruption of PDGF-A function, or of Xwnt6, decreased the polarization of explant contact behavior. Second, the Wnt receptor Xfz7 acted upstream of the kinase Pak1 to control explant fusion independently of PDGF-A-promoted lamellipodia stability. Third, ephrinB1 acted with Dishevelled (Dvl) in front-to-back explant fusion. The second and third modules have been identified previously as regulators of tissue separation at the ectoderm-mesoderm boundary. On non-polarizing, fibronectin-coated substratum, they controlled repulsion between explants in the same way as between tissues during boundary formation. However, explant repulsion/fusion responses were reversed on conditioned substratum by the endogenous guidance cues that also control oriented contact inhibition of lamellipodia. Together, control modules and substratum-bound guidance cues combine preferential front-back adhesion and diminished lateral adhesion of cells to promote collective directional mesoderm migration.
PMID:37732810 | DOI:10.1387/ijdb.230123rw
Genomic epidemiology of <em>Neisseria gonorrhoeae</em> in Shenzhen, China, during 2019-2020: increased spread of ceftriaxone-resistant isolates brings insights for strengthening public health responses
Microbiol Spectr. 2023 Sep 21:e0172823. doi: 10.1128/spectrum.01728-23. Online ahead of print.
ABSTRACT
The antimicrobial resistance (AMR) in gonorrhea poses global threat of increasing public health concern. In response to this concern, molecular surveillance has been widely utilized to detail the changes in the evolution and distribution of Neisseria gonorrhoeae during AMR transmission. In this study, we performed a comprehensive molecular surveillance of 664 N. gonorrhoeae isolates collected in Shenzhen, one of the cities with the largest mobile population in China, 2019-2020. In 2020, ceftriaxone showed an unprecedented high resistance rate of 24.87%, and 67.83% of the ceftriaxone-resistant (Cro-R) isolates harbored a nonmosaic penA allele. The Cro-R isolates with nonmosaic penA alleles showed a tremendous increasing trend from 0.00% in 2014 to 20.45% in 2020, which proves the need for monitoring nonmosaic penA-related resistance. Importantly, genotyping indicated that multilocus sequence typing ST11231 (35.71%) had a notable rate of ceftriaxone resistance, which might become the focus of future surveillance. Whole-genome sequencing analysis showed that the internationally spreading FC428 clones have circulated in Shenzhen region with typical ceftriaxone resistance (MIC ≥ 0.5 mg/L) maintained. Our surveillance combined with genomic analysis provides current information to update gonorrhea management guidelines and emphasizes that continuous AMR surveillance for N. gonorrhoeae is essential. IMPORTANCE We conducted a comprehensive molecular epidemiology analysis for antimicrobial-resistant Neisseria gonorrhoeae in Shenzhen during 2019-2020, which provided important data for personalized treatment and adjustment of monitoring strategy. Briefly, the proportion of ceftriaxone-resistant (Cro-R) isolates reached a stunning prevalence rate of 24.87% in 2020. A typical increment of Cro-R isolates with nonmosaic penA alleles proves the necessity of monitoring nonmosaic AMR mechanism and involving it into developing molecular detection methods. Whole-genome sequencing analysis showed that the international spreading FC428 clone has been circulating in Shenzhen with typical ceftriaxone resistance (MIC ≥ 0.5 mg/L) maintained. In summary, we conducted a comprehensive epidemiology study, providing significant data for therapy management. Our results not only improve the understanding of the distribution and transmission of AMR in N. gonorrhoeae but also provide effective AMR data for improving surveillance strategies in China.
PMID:37732794 | DOI:10.1128/spectrum.01728-23
Inhibitory effect of natural flavone luteolin on <em>Streptococcus mutans</em> biofilm formation
Microbiol Spectr. 2023 Sep 21:e0522322. doi: 10.1128/spectrum.05223-22. Online ahead of print.
ABSTRACT
Streptococcus mutans is one of the key pathogens responsible for dental caries, which is known to be one of the most prevalent biofilm-associated diseases worldwide. S. mutans virulence strongly depends on its biofilm formation and enamel demineralization abilities due to the production of surface adhesins, exopolysaccharides, and acid in the presence of sugar. Luteolin is an abundant natural flavone with a prominent anti-bacterial function. However, it remains unclear how luteolin affects S. mutans pathogenicity including its acidogenicity and biofilm formation. In this study, the effect of luteolin on S. mutans growth, acid production, and its early and late biofilm formation and biofilm disruption was tested. Luteolin shows strong anti-biofilm activity, while it remains non-toxic for bacterial cell viability. In the biofilm, luteolin reduces the expression of S. mutans virulence genes such as gbpC, spaP, gtfBCD, and ftf encoding for surface adhesins and extracellular polysaccharides (EPS)-producing enzymes, which reflects in the strong reduction of bacteria and EPS. Further, it reduces water-insoluble glucan production in the biofilm, potentially, via direct interference with glucosyltransfereases (Gtfs). Moreover, at biofilm inhibitory concentrations, luteolin significantly reduces acid production by S. mutans. Finally, luteolin could target S. mutans amyloid proteins to disrupt the biofilm based on the observation that it inhibits the uptake of the amyloid dye, thioflavin T, by S. mutans extracellular proteins and failed to inhibit biofilm formation by the mutant strain lacking three main amyloid proteins. In conclusion, luteolin appears to be a potent natural compound with pleiotropic anti-biofilm properties against one of the main cariogenic human pathogens, S. mutans. IMPORTANCE Flavonoids are natural compounds with proven anti-bacterial and anti-biofilm properties. Here, we describe the anti-biofilm properties of natural flavone luteolin against the main cariogenic bacteria, S. mutans. Luteolin inhibited gene expression of cell surface adhesins, fructosyltransferases, and glucosyltransferases, which promotes a significant reduction of bacterial and EPS biomass in early and late biofilms. Moreover, luteolin could directly target S. mutans Gtfs and functional amyloids to modulate pathogenic biofilms. These observations provide important insights into the anti-biofilm properties of luteolin while laying out a framework for future therapeutic strategies targeting biofilm-associated virulence factors of oral pathogens.
PMID:37732737 | DOI:10.1128/spectrum.05223-22
STARGATE-X: a Python package for statistical analysis on the REACTOME network
J Integr Bioinform. 2023 Sep 21. doi: 10.1515/jib-2022-0029. Online ahead of print.
ABSTRACT
Many important aspects of biological knowledge at the molecular level can be represented by pathways. Through their analysis, we gain mechanistic insights and interpret lists of interesting genes from experiments (usually omics and functional genomic experiments). As a result, pathways play a central role in the development of bioinformatics methods and tools for computing predictions from known molecular-level mechanisms. Qualitative as well as quantitative knowledge about pathways can be effectively represented through biochemical networks linking the biochemical reactions and the compounds (e.g., proteins) occurring in the considered pathways. So, repositories providing biochemical networks for known pathways play a central role in bioinformatics and in systems biology. Here we focus on Reactome, a free, comprehensive, and widely used repository for biochemical networks and pathways. In this paper, we: (1) introduce a tool StARGate-X (STatistical Analysis of the Reactome multi-GrAph Through nEtworkX) to carry out an automated analysis of the connectivity properties of Reactome biochemical reaction network and of its biological hierarchy (i.e., cell compartments, namely, the closed parts within the cytosol, usually surrounded by a membrane); the code is freely available at https://github.com/marinoandrea/stargate-x; (2) show the effectiveness of our tool by providing an analysis of the Reactome network, in terms of centrality measures, with respect to in- and out-degree. As an example of usage of StARGate-X, we provide a detailed automated analysis of the Reactome network, in terms of centrality measures. We focus both on the subgraphs induced by single compartments and on the graph whose nodes are the strongly connected components. To the best of our knowledge, this is the first freely available tool that enables automatic analysis of the large biochemical network within Reactome through easy-to-use APIs (Application Programming Interfaces).
PMID:37732505 | DOI:10.1515/jib-2022-0029
Identification of novel metallo-β-lactamases inhibitors using ligand-based pharmacophore modelling and structure-based virtual screening
J Biomol Struct Dyn. 2023 Sep 21:1-16. doi: 10.1080/07391102.2023.2258406. Online ahead of print.
ABSTRACT
Metallo-β-lactamases (MBLs) are a group of enzymes that hydrolyze the most commonly used β-lactam-based antibiotics, leading to the development of multi-drug resistance. The three main clinically relevant groups of these enzymes are IMP, VIM, and NDM. This study aims to introduce potent novel overlapped candidates from a ZINC database retrieved from the 200,583-member natural library against the active sites of IMP-1, VIM-2, and NDM-1 through a straightforward computational workflow using virtual screening approaches. The screening pipeline started by assessing Lipinski's rule of five (RO5), drug-likeness, and pan-assay interference compounds (PAINS) which were used to generate a pharmacophore model using D-captopril as a standard inhibitor. The process was followed by the consensus docking protocol and molecular dynamic (MD) simulation combined with the molecular mechanics Poisson-Boltzmann Surface Area (MM-PBSA) method to compute the total binding free energy and evaluate the binding characteristics. The absorption, distribution, metabolism, elimination, and toxicity (ADMET) profiles of the compounds were also analyzed, and the search space decreased to the final two inhibitory candidates for B1 subclass MBLs, which fulfilled all criteria for further experimental evaluation.Communicated by Ramaswamy H. Sarma.
PMID:37732367 | DOI:10.1080/07391102.2023.2258406
Development of genomic resources for Rhodes grass (<em>Chloris gayana</em>), draft genome and annotated variant discovery
Front Plant Sci. 2023 Sep 4;14:1239290. doi: 10.3389/fpls.2023.1239290. eCollection 2023.
ABSTRACT
Genomic resources for grasses, especially warm-season grasses are limited despite their commercial and environmental importance. Here, we report the first annotated draft whole genome sequence for diploid Rhodes grass (Chloris gayana), a tropical C4 species. Generated using long read nanopore sequencing and assembled using the Flye software package, the assembled genome is 603 Mbp in size and comprises 5,233 fragments that were annotated using the GenSas pipeline. The annotated genome has 46,087 predicted genes corresponding to 92.0% of the expected genomic content present via BUSCO analysis. Gene ontology terms and repetitive elements are identified and discussed. An additional 94 individual plant genotypes originating from three diploid and two tetraploid Rhodes grass cultivars were short-read whole genome resequenced (WGR) to generate a single nucleotide polymorphism (SNP) resource for the species that can be used to elucidate inter- and intra-cultivar relationships across both ploidy levels. A total of 75,777 high quality SNPs were used to generate a phylogenetic tree, highlighting the diversity present within the cultivars which agreed with the known breeding history. Differentiation was observed between diploid and tetraploid cultivars. The WGR data were also used to provide insights into the nature and evolution of the tetraploid status of the species, with results largely agreeing with the published literature that the tetraploids are autotetraploid.
PMID:37731974 | PMC:PMC10507473 | DOI:10.3389/fpls.2023.1239290
Use of Interactive Simulations in Fundamentals of Biochemistry, a LibreText Online Educational Resource, to Promote Understanding of Dynamic Reactions
ArXiv. 2023 Sep 7:arXiv:2309.04039v1. Preprint.
ABSTRACT
Biology is perhaps the most complex of the sciences, given the incredible variety of chemical species that are interconnected in spatial and temporal pathways that are daunting to understand. Their interconnections lead to emergent properties such as memory, consciousness, and recognition of self and non-self. To understand how these interconnected reactions lead to cellular life characterized by activation, inhibition, regulation, homeostasis, and adaptation, computational analyses and simulations are essential, a fact recognized by the biological communities. At the same time, students struggle to understand and apply binding and kinetic analyses for the simplest reactions such as the irreversible first-order conversion of a single reactant to a product. This likely results from cognitive difficulties in combining structural, chemical, mathematical, and textual descriptions of binding and catalytic reactions. To help students better understand dynamic reactions and their analyses, we have introduced two kinds of interactive graphs and simulations into the online educational resource, Fundamentals of Biochemistry, a multivolume biochemistry textbook that is part of the LibreText collection. One type is available for simple binding and kinetic reactions. The other displays progress curves (concentrations vs time) for both simple reactions and more complex metabolic and signal transduction pathways, including those available through databases using systems biology markup language (SBML) files. Users can move sliders to change dissociation and kinetic constants as well as initial concentrations and see instantaneous changes in the graphs. They can also export data into a spreadsheet for further processing, such as producing derivative Lineweaver-Burk and traditional Michaelis-Menten graphs of initial velocity (v0) vs substrate concentration.
PMID:37731655 | PMC:PMC10508828
MakeSBML: A tool for converting between Antimony and SBML
ArXiv. 2023 Sep 6:arXiv:2309.03344v1. Preprint.
ABSTRACT
We describe a web-based tool, MakeSBML (https://sys-bio.github.io/makesbml/), that provides an installation-free application for creating, editing, and searching the Biomodels repository for SBML-based models. MakeSBML is a client-based web application that translates models expressed in human-readable Antimony to the System Biology Markup Language (SBML) and vice-versa. Since MakeSBML is a web-based application it requires no installation on the user's part. Currently, MakeSBML is hosted on a GitHub page where the client-based design makes it trivial to move to other hosts. This model for software deployment also reduces maintenance costs since an active server is not required. The SBML modeling language is often used in systems biology research to describe complex biochemical networks and makes reproducing models much easier. However, SBML is designed to be computer-readable, not human-readable. We therefore employ the human-readable Antimony language to make it easy to create and edit SBML models.
PMID:37731653 | PMC:PMC10508829
Assessment of safety and intranasal neutralizing antibodies of HPMC-based human anti-SARS-CoV-2 IgG1 nasal spray in healthy volunteers
Sci Rep. 2023 Sep 20;13(1):15648. doi: 10.1038/s41598-023-42539-7.
ABSTRACT
An HPMC-based nasal spray solution containing human IgG1 antibodies against SARS-CoV-2 (nasal antibody spray or NAS) was developed to strengthen COVID-19 management. NAS exhibited potent broadly neutralizing activities against SARS-CoV-2 with PVNT50 values ranging from 0.0035 to 3.1997 μg/ml for the following variants of concern (ranked from lowest to highest): Alpha, Beta, Gamma, ancestral, Delta, Omicron BA.1, BA.2, BA.4/5, and BA.2.75. Biocompatibility assessment showed no potential biological risks. Intranasal NAS administration in rats showed no circulatory presence of human IgG1 anti-SARS-CoV-2 antibodies within 120 h. A double-blind, randomized, placebo-controlled trial (NCT05358873) was conducted on 36 healthy volunteers who received either NAS or a normal saline nasal spray. Safety of the thrice-daily intranasal administration for 7 days was assessed using nasal sinuscopy, adverse event recording, and self-reporting questionnaires. NAS was well tolerated, with no significant adverse effects during the 14 days of the study. The SARS-CoV-2 neutralizing antibodies were detected based on the signal inhibition percent (SIP) in nasal fluids pre- and post-administration using a SARS-CoV-2 surrogate virus neutralization test. SIP values in nasal fluids collected immediately or 6 h after NAS application were significantly increased from baseline for all three variants tested, including ancestral, Delta, and Omicron BA.2. In conclusion, NAS was safe for intranasal use in humans to increase neutralizing antibodies in nasal fluids that lasted at least 6 h.
PMID:37730833 | DOI:10.1038/s41598-023-42539-7
Genetic reversal of the globin switch concurrently modulates both fetal and sickle hemoglobin and reduces red cell sickling
Nat Commun. 2023 Sep 20;14(1):5850. doi: 10.1038/s41467-023-40923-5.
ABSTRACT
We previously reported initial clinical results of post-transcriptional gene silencing of BCL11A expression (NCT03282656) reversing the fetal to adult hemoglobin switch. A goal of this approach is to increase fetal hemoglobin (HbF) expression while coordinately reducing sickle hemoglobin (HbS) expression. The resulting combinatorial effect should prove effective in inhibiting HbS polymerization at lower physiologic oxygen values thereby mitigating disease complications. Here we report results of exploratory single-cell analysis of patients in which BCL11A is targeted molecularly and compare results with cells of patients treated with hydroxyurea (HU), the current standard of care. We use single-cell assays to assess HbF, HbS, oxygen saturation, and hemoglobin polymer content in RBCs for nine gene therapy trial subjects (BCLshmiR, median HbF% = 27.9) and compare them to 10 HU-treated subjects demonstrating high and comparable levels of HbF (HU High Responders, median HbF% = 27.0). All BCL11A patients achieved the primary endpoint for NCT03282656, which was defined by an absolute neutrophil count greater than or equal to 0.5 × 109 cells/L for three consecutive days, achieved within 7 weeks following infusion. Flow cytometric assessment of single-RBC HbF and HbS shows fewer RBCs with high HbS% that would be most susceptible to sickling in BCLshmiR vs. HU High Responders: median 42% of RBCs with HbS%>70% in BCLshmiR vs. 61% in HU High Responders (p = 0.004). BCLshmiR subjects also demonstrate more RBCs resistant to HbS polymerization at lower physiologic oxygen tension: median 32% vs. 25% in HU High Responders (p = 0.006). Gene therapy-induced BCL11A down-regulation reverses the fetal-to-adult hemoglobin switch and induces RBCs with higher HbF%, lower HbS%, and greater resistance to deoxygenation-induced polymerization in clinical trial subjects compared with a cohort of highly responsive hydroxyurea-treated subjects.
PMID:37730674 | DOI:10.1038/s41467-023-40923-5
DISCERN: deep single-cell expression reconstruction for improved cell clustering and cell subtype and state detection
Genome Biol. 2023 Sep 20;24(1):212. doi: 10.1186/s13059-023-03049-x.
ABSTRACT
BACKGROUND: Single-cell sequencing provides detailed insights into biological processes including cell differentiation and identity. While providing deep cell-specific information, the method suffers from technical constraints, most notably a limited number of expressed genes per cell, which leads to suboptimal clustering and cell type identification.
RESULTS: Here, we present DISCERN, a novel deep generative network that precisely reconstructs missing single-cell gene expression using a reference dataset. DISCERN outperforms competing algorithms in expression inference resulting in greatly improved cell clustering, cell type and activity detection, and insights into the cellular regulation of disease. We show that DISCERN is robust against differences between batches and is able to keep biological differences between batches, which is a common problem for imputation and batch correction algorithms. We use DISCERN to detect two unseen COVID-19-associated T cell types, cytotoxic CD4+ and CD8+ Tc2 T helper cells, with a potential role in adverse disease outcome. We utilize T cell fraction information of patient blood to classify mild or severe COVID-19 with an AUROC of 80% that can serve as a biomarker of disease stage. DISCERN can be easily integrated into existing single-cell sequencing workflow.
CONCLUSIONS: Thus, DISCERN is a flexible tool for reconstructing missing single-cell gene expression using a reference dataset and can easily be applied to a variety of data sets yielding novel insights, e.g., into disease mechanisms.
PMID:37730638 | DOI:10.1186/s13059-023-03049-x
A fully automated FAIMS-DIA mass spectrometry-based proteomic pipeline
Cell Rep Methods. 2023 Sep 13:100593. doi: 10.1016/j.crmeth.2023.100593. Online ahead of print.
ABSTRACT
Here, we present a standardized, "off-the-shelf" proteomics pipeline working in a single 96-well plate to achieve deep coverage of cellular proteomes with high throughput and scalability. This integrated pipeline streamlines a fully automated sample preparation platform, a data-independent acquisition (DIA) coupled with high-field asymmetric waveform ion mobility spectrometer (FAIMS) interface, and an optimized library-free DIA database search strategy. Our systematic evaluation of FAIMS-DIA showing single compensation voltage (CV) at -35 V not only yields the deepest proteome coverage but also best correlates with DIA without FAIMS. Our in-depth comparison of direct-DIA database search engines shows that Spectronaut outperforms others, providing the highest quantifiable proteins. Next, we apply three common DIA strategies in characterizing human induced pluripotent stem cell (iPSC)-derived neurons and show single-shot mass spectrometry (MS) using single-CV (-35 V)-FAIMS-DIA results in >9,000 quantifiable proteins with <10% missing values, as well as superior reproducibility and accuracy compared with other existing DIA methods.
PMID:37729920 | DOI:10.1016/j.crmeth.2023.100593
Spatially aware deep learning reveals tumor heterogeneity patterns that encode distinct kidney cancer states
Cell Rep Med. 2023 Sep 19;4(9):101189. doi: 10.1016/j.xcrm.2023.101189.
ABSTRACT
Clear cell renal cell carcinoma (ccRCC) is molecularly heterogeneous, immune infiltrated, and selectively sensitive to immune checkpoint inhibition (ICI). However, the joint tumor-immune states that mediate ICI response remain elusive. We develop spatially aware deep-learning models of tumor and immune features to learn representations of ccRCC tumors using diagnostic whole-slide images (WSIs) in untreated and treated contexts (n = 1,102 patients). We identify patterns of grade heterogeneity in WSIs not achievable through human pathologist analysis, and these graph-based "microheterogeneity" structures associate with PBRM1 loss of function and with patient outcomes. Joint analysis of tumor phenotypes and immune infiltration identifies a subpopulation of highly infiltrated, microheterogeneous tumors responsive to ICI. In paired multiplex immunofluorescence images of ccRCC, microheterogeneity associates with greater PD1 activation in CD8+ lymphocytes and increased tumor-immune interactions. Our work reveals spatially interacting tumor-immune structures underlying ccRCC biology that may also inform selective response to ICI.
PMID:37729872 | DOI:10.1016/j.xcrm.2023.101189
TP63 fusions drive multicomplex enhancer rewiring, lymphomagenesis, and EZH2 dependence
Sci Transl Med. 2023 Sep 20;15(714):eadi7244. doi: 10.1126/scitranslmed.adi7244. Epub 2023 Sep 20.
ABSTRACT
Gene fusions involving tumor protein p63 gene (TP63) occur in multiple T and B cell lymphomas and portend a dismal prognosis for patients. The function and mechanisms of TP63 fusions remain unclear, and there is no target therapy for patients with lymphoma harboring TP63 fusions. Here, we show that TP63 fusions act as bona fide oncogenes and are essential for fusion-positive lymphomas. Transgenic mice expressing TBL1XR1::TP63, the most common TP63 fusion, develop diverse lymphomas that recapitulate multiple human T and B cell lymphomas. Here, we identify that TP63 fusions coordinate the recruitment of two epigenetic modifying complexes, the nuclear receptor corepressor (NCoR)-histone deacetylase 3 (HDAC3) by the N-terminal TP63 fusion partner and the lysine methyltransferase 2D (KMT2D) by the C-terminal TP63 component, which are both required for fusion-dependent survival. TBL1XR1::TP63 localization at enhancers drives a unique cell state that involves up-regulation of MYC and the polycomb repressor complex 2 (PRC2) components EED and EZH2. Inhibiting EZH2 with the therapeutic agent valemetostat is highly effective at treating transgenic lymphoma murine models, xenografts, and patient-derived xenografts harboring TP63 fusions. One patient with TP63-rearranged lymphoma showed a rapid response to valemetostat treatment. In summary, TP63 fusions link partner components that, together, coordinate multiple epigenetic complexes, resulting in therapeutic vulnerability to EZH2 inhibition.
PMID:37729434 | DOI:10.1126/scitranslmed.adi7244
Simultaneous electrophysiology and optogenetic perturbation of the same neurons in chronically implanted animals using μLED silicon probes
STAR Protoc. 2023 Sep 18;4(4):102570. doi: 10.1016/j.xpro.2023.102570. Online ahead of print.
ABSTRACT
Micro-light-emitting-diode (μLED) silicon probes feature independently controllable miniature light-emitting-diodes (LEDs) embedded at several positions in each shank of a multi-shank probe, enabling temporally and spatially precise optogenetic neural circuit interrogation. Here, we present a protocol for performing causal and reproducible neural circuit manipulations in chronically implanted, freely moving animals. We describe steps for introducing optogenetic constructs, preparing and implanting a μLED probe, performing simultaneous in vivo electrophysiology with focal optogenetic perturbation, and recovering a probe following termination of an experiment. For complete details on the use and execution of this protocol, please refer to Watkins de Jong et al. (2023).1.
PMID:37729059 | DOI:10.1016/j.xpro.2023.102570
The C-terminus of α-Synuclein regulates its dynamic cellular internalization by Neurexin 1β
Mol Biol Cell. 2023 Sep 20:mbcE22110496. doi: 10.1091/mbc.E22-11-0496. Online ahead of print.
ABSTRACT
The aggregation of the disordered neuronal protein, α-Synuclein (αS), is the primary pathological feature of Parkinson's disease. Current hypotheses favor cell-to-cell spread of αS species as underlying disease progression, driving interest in identifying the molecular species and cellular processes involved in cellular internalization of αS. Prior work from our lab identified the chemically specific interaction between αS and the pre-synaptic adhesion protein neurexin 1β (N1β) to be capable of driving cellular internalization of both monomer and aggregated forms of αS. Here we explore the physical basis of N1β-driven internalization of αS. Specifically, we show that spontaneous internalization of αS by SH-SY5Y and HEK293 cells expressing N1β requires essentially all of the membrane-binding domain of αS; αS constructs truncated beyond residue 90 bind to N1β in the plasma membrane of HEK cells, but are not internalized. Interestingly, prior to internalization, αS and N1β co-diffuse rapidly in the plasma membrane. αS constructs that are not internalized show very slow mobility themselves, as well as slow N1β diffusion. Finally, we find that truncated αS is capable of blocking internalization of full-length αS. Our results draw attention to the potential therapeutic value of blocking αS-N1β interactions.
PMID:37729016 | DOI:10.1091/mbc.E22-11-0496
Corrigendum: Epidemiology of flavescence dorée and hazelnut decline in Slovenia: geographical distribution and genetic diversity of the associated 16SrV phytoplasmas
Front Plant Sci. 2023 Aug 31;14:1261658. doi: 10.3389/fpls.2023.1261658. eCollection 2023.
ABSTRACT
[This corrects the article DOI: 10.3389/fpls.2023.1217425.].
PMID:37727851 | PMC:PMC10505790 | DOI:10.3389/fpls.2023.1261658
Peripheral neuropathy associated with monomethyl auristatin E-based antibody-drug conjugates
iScience. 2023 Aug 29;26(10):107778. doi: 10.1016/j.isci.2023.107778. eCollection 2023 Oct 20.
ABSTRACT
Since the successful approval of gemtuzumab ozogamicin, antibody-drug conjugates (ADCs) have emerged as a pivotal category of targeted therapies for cancer. Among these ADCs, the use of monomethyl auristatin E (MMAE) as a payload is prevalent in the development of ADC drugs, which has significantly improved overall therapeutic efficacy against various malignancies. However, increasing clinical observations have raised concerns regarding the potential nervous system toxicity associated with MMAE-based ADCs. Specifically, a higher incidence of peripheral neuropathy has been reported in ADCs incorporating MMAE as payloads. Considering the increasing global use of MMAE-based ADCs, it is imperative to provide an inclusive overview of diagnostic and management strategies for this adverse event. In this review, we examine current information and what future research directions are required to better understand and manage this type of clinical challenge.
PMID:37727735 | PMC:PMC10505985 | DOI:10.1016/j.isci.2023.107778