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Huang, Y.

Publications and source records attributed to Huang, Y..

At least 325 records · Page 18Linked to original sources

Deep learning guided discovery of antibacterial polymeric nanoparticles

Drug-resistant bacterial infections pose a serious threat to global health, driving the development of novel antibacterial strategies beyond classic antibiotics. Self-assembled polymeric nanoparticles (SANPs) have emerged as promising candidates due to their unique structural properties, which enhance membrane interaction, drug loading, and therapeutic accumulation. The structural diversity and tunable properties of SANPs provide a flexible design platform for antibacterial applications. However, navigating the vast chemical space of SANPs remains a significant challenge due to the complex structure-activity relationships. To address this, we developed PolyCLOVER, a deep learning-guided framework for the efficient discovery of antibacterial SANPs. The framework integrates multi-stage self-supervised learning, active learning, and high-throughput experimentation to iteratively guide the discovery of SANPs with potent antibacterial activity and low toxicity. Through this framework, we identified three potent SANPs within a combinatorial library of [~]100,000 poly({beta}-amino ester)s, with minimum inhibitory concentrations of 4 g/mL and 8 g/mL against clinically multidrug-resistant S. aureus and A. baumannii, respectively. Moreover, they can also act as antibiotic carriers, restoring the sensitivity of pathogens to penicillin G. In vivo studies demonstrated their therapeutic efficacy both as monotherapies and in combination therapies with antibiotics. These results demonstrate PolyCLOVER as a powerful framework for discovering multi-functional SANPs to combat antibiotic resistance.

microbiology↗

Spatially Organized IGF1 mTOR Signaling Controls Human Forebrain Progenitor Fate Through Coordinated Transcriptional and Translational Programs

The specification and maintenance of human forebrain neural progenitor cells (NPCs) depend on both intrinsic gene networks and spatially localized niche signals, but the interplay between these cues remains incompletely understood. Here, we identify a spatially organized, paracrine IGF1 signaling architecture that regulates human FOXG1 NPCs through multilayered transcriptional and translational control. Using a pluripotent stem cell-derived forebrain model, we show that FOXG1 NPCs express IGF1 receptors but lack endogenous IGF1, instead depending on neighboring epithelial-like domains that secrete IGF1. IGF1 promotes progenitor proliferation, clonal expansion, and vertical tissue growth by activating PI3K-AKT-mTOR and MEK-ERK pathways. Ribosome profiling and 5'UTR reporter assays reveal that mTOR signaling selectively enhances translation of neurodevelopmental and biosynthetic transcripts-- including GSX1, a ventral fate determinant implicated in interneuron specification and autism. These findings uncover a human-specific regulatory mechanism in which spatially restricted IGF1-mTOR signaling integrates niche signals with translational output to support progenitor identity, biosynthetic capacity, and developmental resilience.

neuroscience↗

FASN Inactivation-induced Progranulin (GRN) Expression Promotes Lysosome-dependent Cell Death to Suppress Leukemogenesis

Cancer cells rely on lipogenesis in addition to exogenous lipid uptake, and fatty acid synthase (FASN) is aberrantly overexpressed in myeloid leukemia. However, the precise role of FASN in leukemogenesis in vivo remains elusive. Here, we demonstrated that FASN is essential for leukemogenesis. Ablation of FASN impeded leukemic cell growth, survival, clonogenicity in vitro, and the leukemic burden in vivo. Conditional knockout of FASN barely affected hematopoiesis but significantly attenuated the leukemic progression of MLL-AF9 transplants. By screening a library of platensimycin derivatives, we identified compound MS-C19 as a potent FASN inhibitor. Pharmacological targeting of FASN by MS-C19 suppressed leukemic cell growth and clonogenicity in clinical AML blasts. Mechanistically, both MS-C19 treatment and FASN deficiency triggered the activation of lysosomal and inflammatory gene expression. Loss of FASN led to lysosomal membrane permeabilization and subsequent lysosome-associated cell death, but not lysosome biogenesis. We further identified that GRN, a lysosomal and neuroinflammatory gene, was potently transcribed by TFEB upon FASN loss. Depletion of GRN significantly reversed the inhibitory effects caused by FASN knockdown. Our work demonstrates that FASN is a therapeutic target for myeloid leukemia, and inactivation of FASN by the lead compound MS-C19 provides an alternative approach for leukemic intervention. Key PointsO_LIGenetic ablation of FASN induces apoptosis, impedes leukemia cell growth, and improves the survival of leukemic xenografts. C_LIO_LITargeting FASN by the compound MS-C19, a derivative of the natural microbe antibiotic platensimycin, reduces the cell survival of leukemic cell lines, the clinical leukemic blasts, and MLL-AF9 transformed murine leukemic cells. C_LIO_LIFASN inhibition induces lysosome-dependent cell death that relies on Progranulin (GRN) expression. C_LI

cancer biology↗

APOE genotype confers context dependent neurovascular vulnerability in immune-vascularized human forebrain organoids

The APOE gene is a major genetic determinant of neurovascular and immune function, yet the mechanisms by which its isoforms modulate brain vulnerability to pathogenic stress remain incompletely understood. Here, we employ isogenic human iPSC-derived immune-vascularized--Forebrain Organoid-based Multicellular Assembled Cerebral Organoids (FORMA-COs)--to dissect isoform-specific responses to a clinically relevant viral challenge. We find that APOE2/2 and APOE4/4 FORMA-COs exhibit heightened viral RNA burden and distinct neuroinflammatory profiles compared to APOE3/3. Specifically, APOE4/4 promotes IL-1 and VEGFA induction, whereas APOE2/2 leads to elevated TNF-{beta} and VEGFA protein accumulation, indicating divergent pathways of injury. Integrated transcriptomic analyses, combined with known and predicted APOE protein-protein interaction networks, reveal genotype-dependent enrichment of cytokine signaling, angiogenic remodeling, and immune dysregulation. In vivo validation using humanized mouse models corroborates APOE genotype- specific vascular remodeling, microglial activation, and oligodendrocyte perturbation. These findings demonstrate that APOE genotype confers context-specific susceptibility to neuroimmune and vascular injury, providing insight into genetic risk mechanisms underlying infection-related and neurodegenerative brain disorders.

neuroscience↗

Hippocampal single-cell RNA Atlas of chronic methamphetamine abuse-induced cognitive decline in mice

BackgroundChronic methamphetamine abuse leads to cognitive decline, posing a significant threat to human health and contributing to loss of productivity. However, the intricate and multifaceted mechanisms underlying methamphetamine-induced neurotoxicity have impeded the development of effective therapeutic interventions. MethodsTo establish a mouse model of cognitive decline induced by chronic methamphetamine exposure, we employed a large sample size and conducted two behavioral tests (Y-maze and novel object recognition test) at 2 and 4 weeks post-exposure. Subsequently, single-cell RNA sequencing was utilized to delineate the mRNA expression profiles of individual cells within the hippocampus. Comprehensive bioinformatics analyses, including cell clustering and identification, differential gene expression analysis, cellular communication analysis, pseudotemporal trajectory analysis, and transcription factor regulation analysis, were performed to elucidate the cellular-level changes in mRNA profiles caused by chronic methamphetamine exposure. ResultsOur findings demonstrated impairments in working memory, spatial cognition, learning, and cognitive memory. After 4 weeks of behavioral testing, we identified diverse cell types in the hippocampi of METH- and saline-treated mice through scRNA-seq, including glial cells, stromal cells, vascular cells, and immune cells. We observed that methamphetamine exerts cell-specific effects on gene expression changes associated with neuroinflammation, blood-brain barrier disruption, neuronal support dysfunction, and immune dysregulation. Furthermore, cross-talk analysis revealed extensive alterations in cellular communication patterns and signal changes within the hippocampal microenvironment induced by methamphetamine exposure. Pseudotime analysis predicted hippocampal neurogenesis disorders and identified key regulatory genes implicated in chronic methamphetamine abuse. Transcription factor analysis uncovered regulators and pathways linked to astrocyte-mediated neuroinflammation, endothelial junction integrity, microglial synaptic remodeling, and oligodendrocyte-supported neuronal cell bodies and axons. Additionally, it highlighted the role of neural precursor cells in various forms of neurodegeneration. ConclusionsThis study establishes a robust mouse model of cognitive impairment induced by chronic methamphetamine exposure. It provides valuable biological insights, characterizes the single-cell atlas of the hippocampus, and offers novel directions for investigating neurological damage associated with chronic methamphetamine-induced cognitive decline.

pharmacology and toxicology↗

Structural insight into the transcription activation mechanism of the phage Mor/C family activators

Bacteriophage Mu, a temperate phage that infects E. coli K-12 and other enteric bacteria, precisely controls its replication cycle through hijacking host RNA polymerase (RNAP) by the middle operon regulator Mor and the late gene transcription activator C. Though a dimeric arrangement and significant conformational changes are proposed for the distinct Mor/C family activators, the underlying transcription activation mechanism remains unclear. In this study, we present two cryo-EM structures of the transcription activation complex (Mor-TAC and C-TAC) with phage Mu middle and late gene promoters, respectively. Remarkably, the Mor/C activators bind to promoter DNA as a centrosymmetric tetramer rather than as the proposed dimer, concurrently stabilizing by the N-terminal dimerization domains and C-termini. The C-terminal DNA binding domains and two anti-{beta}-strands simultaneously interact with two adjacent DNA major grooves. The activators also engage a variety of interactions with the conserved domains (CTD, {sigma}70R4, and {beta} FTH) of RNAP, providing evidences for a recruitment mechanism. In addition, single-molecule FRET assays show that C significantly enhances RPitc formation, suggesting a different multi-step activation mechanism for C. Collectively, these findings reveal the unique transcription activation mechanism of tetrameric Mor/C family activators, unraveling a novel mode of phage hijacking and bacterial transcription regulation.

biochemistry↗

Plant diversity shapes plant volatile emission differently at the species and community level

Studies have investigated the interactions between plants through competition and resource sharing to understand the mechanisms behind the positive effects of plant diversity on productivity. Volatile organic compounds (VOCs) are important info-chemicals in plant-plant interactions, but they have so far rarely been considered in this context. Here, we measured VOC emissions at both community and species levels (Plantago lanceolata) in experimental plant communities of varying diversity (The Jena Experiment) to understand the role of VOCs in driving biodiversity-ecosystem functioning relationships. We show that plant diversity determines the release of plant VOCs at both levels. At the community level, plant species richness directly enhanced VOC emission and increased VOC richness both directly and indirectly by altering herbivore damage and LAI. At the species level, plant diversity did not directly affect the VOC emissions of P. lanceolata but indirectly affected it by influencing the VOC emissions from the surrounding community. Plantago lanceolata individuals in communities with high concentrations of green leaf volatiles decreased their VOC emission, while those in communities with high concentrations of terpenoids increased their VOC diversity. Our results provide first evidence that plant diversity shapes community-level plant VOC emission and thus influences focal plant VOC emission inside the community.

ecology↗

Hyper-Glycosylation as a Central Metabolic Driver of Alzheimers Disease

Alzheimers disease (AD) is a neurodegenerative disorder characterized by devastating degenerative decline. Metabolic disruptions are widely observed, yet their involvement in the molecular etiology of AD remains underexplored. Utilizing spatial metabolomics, lipidomics, and glycomics in both mouse models and human post-mortem samples, we identified a hyper-glycosylation phenotype as a hallmark of AD. To investigate the underlying mechanisms and whether the observed effect was a driver of the observed decline, we developed an advanced spatial isotopic tracing pulse-chase method to study the dynamics of N-linked glycans. Our analysis revealed enhanced glycan biosynthesis in AD mouse models. Based on these findings, we performed genetic and dietary interventions to modulate glycan biosynthesis. Genetic knockdown of glycan biosynthetic enzymes ameliorated the hyper-glycosylation and improved cognitive and behavioral outcomes in AD mice. In contrast, oral glucosamine supplementation drove hyper-glycosylation and exacerbated cognitive and behavioral deficits. To assess the clinical relevance of these findings, we conducted a retrospective analysis of a large population of patients with mild cognitive impairment (MCI), AD, and Alzheimers Disease Related Dementias (ADRD) stratified by glucosamine use, leveraging electronic health records. Consistently, glucosamine supplementation was associated with increased mortality in AD and ADRD patient cohorts, and significantly elevated progression from MCI to AD compared to age-matched controls. Collectively, our findings establish hyper-glycosylation as a pathological driver of AD and highlight glycan metabolism as an actional target in the fight against AD.

neuroscience↗

Harmonized Protocol for Subfield Segmentation in the Hippocampal Body on High-Resolution in vivo MRI from the Hippocampal Subfields Group (HSG)

Hippocampal subfields differentially develop and age, and they vary in vulnerability to neurodegenerative diseases. Innovation in high-resolution imaging has accelerated clinical research on human hippocampal subfields, but substantial differences in segmentation protocols impede comparisons of results across laboratories. The Hippocampal Subfields Group (HSG) is an international organization seeking to address this issue by developing a histologically-valid, reliable, and freely available segmentation protocol for high-resolution T2-weighted 3 tesla MRI (http://www.hippocampalsubfields.com). Here, we report the first portion of the protocol focused on subfields in the hippocampal body; protocols for the head and tail are in development. The body protocol includes definitions of the internal boundaries between subiculum, Cornu Ammonis (CA) 1-3 subfields, and dentate gyrus, in addition to the external boundaries of the hippocampus apart from surrounding white matter and cerebrospinal fluid. The segmentation protocol is based on a novel histological reference data set labeled by multiple expert neuroanatomists. With broad participation of the research community, we voted on the segmentation protocol via online survey, which included detailed protocol information, feasibility testing, demonstration videos, example segmentations, and labeled histology. All boundary definitions were rated as having high clarity and reached consensus agreement by Delphi procedure. The harmonized body protocol yielded high inter- and intra-rater reliability. In the present paper we report the procedures to develop and test the protocol, as well as the detailed procedures for manual segmentation using the harmonized protocol. The harmonized protocol will significantly facilitate cross-study comparisons and provide increased insight into the structure and function of hippocampal subfields across the lifespan and in neurodegenerative diseases.

neuroscience↗

HIF-1α promotes osteogenic-angiogenic coupling response of BMSCs cell sheets

BackgroundThere is a critical need for management of vascularization in bone tissue engineering. The purpose of this study was to use HIF-1-transduced BMSCs fabricated prevascularized osteogenic cell sheets and explore HIF-1 promoted osteogenic-angiogenic coupling response of BMSCs cell sheets in vitro. MethodsHIF-1 was over-expressed by using a lentiviral vector, and transduced steadily in Wistar rats bone marrow mesenchymal stem cells(BMSCs). Real-time quantitative and western blot were performed to assess the expression level of HIF-1. Then, HIF-1/BMSCs were cultured to form osteogenic cell sheets(OCTs). ALP activity and Alizarin-red staining were performed respectively at day 14 and 21 to detect the characteristic of osteogenesis. Simultaneously, HIF-1/BMSCs were induced to differentiate into endothelial-like cells(iECs) for 14 days, and flow cytometry was further detected the conversion rates of HIF-1/BMSCs to iECs. Finally, iECs were seeded onto the OCTs to construct the prevascularized-osteogenic cell sheets (P-OCTs). In order to detect the role of HIF-1 involved in osteogenic-angiogenic coupling response of P-OCTs, Immunofluorescent staining for CD31 was performed on P-OCTs at 1, 3, 7, 14 days to check the formation of networks, and western blot of osteopontin(OPN) and osteocalcin (OCN) at 1, 7, 14 days to detect bone formation. Meanwhile, the none transduced BMSCs were as control. ConclusionBMSCs were transduced by Lenti-HIF-1 with optimal multiplicity of infection was 30(MOI=30), meanwhile, qPCR and western blot were performed to confirm this result. Next, the flow cytometric analysis results showed the conversion rate of BMSCs differentiated to iECs was 92.43%, which indicated BMSCs transduced by HIF-1 had a great superiority to differentiate into endothelial cells under experimental conditions. Then, ALP at day 14 and Alizarin-red staining at day 21 on OCTs showed an obvious osteogenic differentiation characteristic with more deep stained calcium nodules deposits than the control groups. Finally, we fabricated P-OCTs and observed iECs migrated reticulated fast and formed a large number of lumens and networks in experimental groups. At the same time, the results of Immunofluorescent staining for CD31 at day 1, 3, 7, 14 and osteogenic proteins expressions of OCN,OPN at day 1, 7, 14 showed that HIF-1 could promote osteogenic-angiogenic coupling response in P-OCTs significantly in vitro. All in all, the over-expressed HIF-1 of BMSCs cell sheets strategy can provide a new promising method for bone engineering, and we will detect further in vivo.

bioengineering↗

Dimethyl fumarate reprograms cervical cancer cells to enhance antitumor immunity by activating mtDNA-cGAS-STING pathway

BackgroundCervical cancer (CC) remains a significant global health challenge for women, especially in advanced stages where effective treatments are limited. Current immunotherapies, including PD-1/PD-L1 blockades and adoptive T cell therapies, show limited response rates and durability. Dimethyl fumarate (DMF), an FDA-approved drug for autoimmune diseases, has demonstrated that it might exhibit direct antitumor activity in several cancers. However, its influence on anti-tumor immunity and its function in CC remain poorly understood. This study aims to investigate the therapeutic potential of DMF in CC models and elucidate its underlying mechanisms of action. MethodsCC cell lines and mouse models were treated with DMF. Transcriptional level changes in cervical cancer cells following DMF treatment were analyzed by RNA-seq. Mitochondrial DNA (mtDNA) release, and cGAS-STING activation were assessed via qPCR, immunofluorescence, immunoblotting and ELISA. CD8+ T cell recruitment was analyzed by flow cytometry. Combinatorial therapies (DMF + anti-PD-1/TILs) were tested in syngeneic or patient-derived xenografts (PDX) models. ResultsDMF treatment induces mitochondrial dysfunction in tumor cells, resulting in the release of mtDNA into the cytosol. The cytosolic mtDNA activates the cGAS-STING-TBK1 pathway and type I interferon response, leading to the secretion of CCL5 and CXCL10, thereby enhancing CD8 T cell infiltration. Additionally, DMF exhibits synergistic effect with PD-1 blockade in murine CC model, and can enhance the therapeutic efficacy of adoptively transferred T cells toward CC patient-derived xenografts model. ConclusionThis work elucidated that DMF reprograms CC cells to activate the mtDNA-cGAS-STING pathway, fostering a chemokine-rich microenvironment that recruits CD8+ T cells. Its synergy with PD-1 blockade or TIL therapy underscores its potential as an immunomodulatory adjuvant. These findings suggest that DMF holds promise as a novel immunotherapeutic strategy for improving clinical outcomes in CC.

immunology↗

CASTOR1: A Novel Tumor Suppressor Linking mTORC1 and KRAS Pathways in Tumorigenesis and Resistance to KRAS-Targeted Therapies in Non-Small Cell Lung Cancer

Cytosolic arginine sensor for mTORC1 Subunit 1 (CASTOR1) functions as a key regulator of mechanistic target of rapamycin complex 1 (mTORC1) signaling. Despite its frequent dysregulation in cancers via mechanisms such as KSHV microRNA-mediated inhibition or AKT-driven phosphorylation and degradation, the impact of CASTOR1 loss on tumor initiation and progression remains poorly understood. Here, we identify CASTOR1 as a critical tumor suppressor in non-small cell lung cancer (NSCLC) by demonstrating that its genetic ablation amplifies tumorigenesis in a KRAS-driven genetically engineered mouse model (GEMM;LSL-KRASG12D). CASTOR1 deficiency markedly enhances lung tumor incidence, accelerates tumor progression, and increases proliferative indices in KRASG12D-driven tumors (KRASG12D;C1KO) compared to CASTOR1 wild type (WT) tumors (KRASG12D;C1WT). Advanced-stage tumors exhibit elevated phosphorylated CASTOR1 (pCASTOR1) and reduced total CASTOR1 levels, suggesting active degradation during tumorigenesis. Mechanistically, CASTOR1 loss amplifies mTORC1 signaling, as evidenced by heightened phosphorylation of downstream effectors 4EBP1 and S6, while also augmenting AKT and ERK activation, uncovering a crosstalk between the PI3K/AKT/mTORC1 and KRAS/ERK pathways. Furthermore, CASTOR1 ablation induces genome instability, which may contribute to enhanced tumor incidence and progression. Importantly, CASTOR1 deficiency confers resistance to KRASG12D-specific inhibitors, while over half of KRASG12D;C1WT tumors also display resistance. Organoids derived from KRASG12D;C1KO and KRASG12D;C1WT tumors reveal a correlation between KRAS inhibitor resistance and hyperactivation of mTORC1, with mTORC1 and PI3K inhibitors sensitizing resistant tumors to KRASG12D-targeted therapies. These findings position CASTOR1 as a novel tumor suppressor that modulates mTORC1 and KRAS signaling to constrain NSCLC progression. Our study further highlights the therapeutic potential of combining mTORC1 or ERK inhibitors with KRAS-targeted therapies for NSCLC characterized by hyperactive KRAS signaling and impaired CASTOR1 activity. HighlightsO_LICASTOR1 functions as a tumor suppressor in NSCLC by limiting KRAS-driven tumor initiation and progression. C_LIO_LICASTOR1 is frequently lost or inactivated in wild-type tumors during tumor progression, contributing to advanced-stage malignancies. C_LIO_LICASTOR1 deficiency amplifies mTORC1 signaling and enhances PI3K/AKT and KRAS/ERK crosstalk, driving tumorigenesis and resistance to KRAS-specific inhibitors. C_LIO_LICombining mTORC1 or PI3K inhibitors with KRAS-targeted therapies effectively overcomes resistance in KRAS-driven NSCLC. C_LI

cancer biology↗

Mesoscopic SCAPE Microscope with a Rescanned, Super-oblique Illumination Plane

Investigating structural and functional dynamics across large spatial scales in living organisms calls for volumetric microscopy that combines a wide field of view (FOV), high spatial resolution, and sufficient temporal resolution. Swept confocally-aligned planar excitation (SCAPE) microscopy offers a compelling balance of optical sectioning, cellular resolution, and high-speed volumetric imaging. However, extending SCAPE to mesoscopic scales has been hindered by the limited tilting angle of the oblique illumination light sheet achievable with commercial low-magnification objectives. Here, we present a mesoscopic SCAPE microscope that overcomes this constraint by implementing a super-oblique light sheet--tilted up to ~60{degrees} relative to the optical axis of a 0.5-NA primary objective--enabled by an air-to-water bridging reflector. In addition, we introduce a single-galvanometer, self-conjugating rescanning strategy that allows arbitrary customization of the optical-to-mechanical angle ratio. This innovation accommodates the reversed and modulated scan displacement of the reflected light sheet and preserves descanned epi-fluorescence detection. Together, these advancements enable our mesoscopic SCAPE microscope to achieve a lateral FOV of 5.0 mm x 2.9 mm, cellular-level spatial resolution (~9.4 m x ~5.9 m lateral, and ~6.0 m axial), and a volumetric imaging rate of 9 volumes per second.

bioengineering↗

Mapping the functional differentiation and interactions among the inferior, medial frontal and posterior temporal cortex in semantic control

Semantic control refers to the ability to flexibly retrieve and manipulate stored knowledge to support context-appropriate behavior. A left-lateralized network comprising the left inferior frontal gyrus (IFG), posterior middle temporal gyrus (pMTG), and dorsal medial prefrontal cortex (dmPFC) has been consistently implicated in this process. While previous studies have established the necessity of the IFG and pMTG in semantic control, the causal role of the left dmPFC remains unclear. Additionally, it is unknown whether each of these three regions exhibits internal functional differentiation and how they interact to support semantic control. To address these questions, we combined task-based functional magnetic resonance imaging (fMRI) with fMRI-guided transcranial magnetic stimulation (TMS). We found that dmPFC, like IFG and pMTG, is causally involved in semantic control. All three regions exhibited a consistent anterior-posterior functional gradient: anterior subregions were selectively engaged during high-demand semantic processing, whereas posterior subregions responded to both easy and hard tasks. Furthermore, combined activation patterns of these regions better predicted the behavioral differences between hard and easy semantic tasks compared to the activation patterns of any single region. Semantic control modulated both the autoinhibition within individual regions and the functional connectivity among them, suggesting these regions operate in a coordinated network rather than in isolation. These findings advance our understanding of the neural architecture supporting flexible semantic behavior. Significance StatementUnderstanding how the brain supports flexible semantic behavior is critical for both cognitive neuroscience and clinical neuropsychology. While prior studies have consistently implicated the left IFG, pMTG, and dmPFC in semantic control, the causal contribution of the dmPFC and the functional dynamics among these regions have remained unclear. This study provides the first causal evidence for the dmPFCs role in semantic control, reveals functional differentiation within the IFG and pMTG, and shows that these regions interact as an integrated network. These findings challenge the notion of functionally homogeneous control nodes and highlight a topographically organized, interactive system underlying controlled semantic retrieval. This work refines our mechanistic understanding of semantic control and may inform clinical models of language and conceptual deficits.

neuroscience↗

Mesoscopic whole-brain T2*-weighted and associated quantitative MRI in healthy humans at 10.5 T

PurposeTo demonstrate the feasibility and performance of mesoscopic whole brain T2*-weighted (T2*w) MRI at 10.5 T by combining a motion-robust multi-echo gradient-echo (GRE) method with high-density RF receive arrays. MethodsMulti-echo GRE data were collected in healthy adults at isotropic 0.5 mm resolution using a custom-built 16-channel transmit/80-channel receive (16Tx/80Rx) RF coil. Whole brain images were reconstructed with navigator-guided joint motion and field correction and were used for quantitative R2* and susceptibility ({chi}) mapping. Intrinsic signal-to-noise ratio (iSNR) and quantification precision for R2* and{chi} were also estimated. The results were compared with those obtained in the same subjects with matched resolution at 7 T using the commercial Nova 1Tx/32Rx coil, to demonstrate the iSNR and quantification precision gains at 10.5 T. G-factors were also calculated at each field strength to evaluate parallel imaging performances. To demonstrate the benefit of increased parallel imaging performances at 10.5 T, whole brain images with higher acceleration were also obtained using a custom-built 16Tx/128Rx coil. Resultsthe utilized motion robust GRE sequence and reconstruction effectively reduced artifacts from motion and field changes during scans, producing high-quality whole-brain T2*w images and multi-parametric maps at 10.5 T with delineation of fine-scale brain structures. Compared to 7 T, the 10.5 T approach led to gains in both iSNR and quantification precision of R2* and{chi} . Quantitatively, iSNR estimated in the peripheral cortical gray matter increased by 42%. Parallel imaging performances were also improved at 10.5 T owing to the utilized high-density coils compared to the commonly used commercially available coil at 7 T, allowing high-quality images with up to 12-fold combined acceleration when using the 128Rx coil. ConclusionIt is feasible to perform motion-robust whole-brain mesoscopic multi-echo gradient echo imaging of the human brain at 10.5 T. Intrinsic SNR and quantification precision of R2* and{chi} were estimated and compared with 7 T results. The results presented here may shed light on future optimal implementation of anatomic T2*w brain MRI at ultrahigh field beyond 7 T.

bioengineering↗

ER fusogens maintain membrane reservoir to ensure brain function

How the morphological dynamics of the endoplasmic reticulum (ER) are linked to its functions is unclear. Atlastins (ATLs), a class of GTPases, mediate ER fusion, and human mutations in ATL1 cause hereditary spastic paraplegia (HSP). Here, we show that ATL2-knockout mice are embryonic lethal with compromised development, particularly of the cerebellum. ATL2 is highly expressed in neuroglia, though ATL1 is dominant in the brain. Lack of ATL2 disorganizes the positioning of Bergmann glia, which in turn interferes with granule cell migration. These cells have significant shrinkage in the intracellular membrane area, which is associated with decreased phosphatidylcholine and cholesterol synthesis. When tested in calyx-type synapses in ATL-deleted mice, a reduced membrane reservoir, represented by fewer presynaptic vesicles, leads to defective synaptic function and deafness. Collectively, these findings suggest that ER-shaping activity by ATL is essential for sustained lipid synthesis, and boosted lipid uptake is potentially beneficial for HSP patients.

neuroscience↗

Capturing Natural Evolution in Function-guided RNA Design via Genomic Foundation Models

RNAs play critical roles in gene expression regulation, catalysis, genetic information transmission, and immune response. However, current RNA engineering approaches face limitations in designing RNA for efficient in vivo folding and functional execution. Here, we present a novel, zero-shot strategy that integrates genomic large language models (LLMs) with inverse folding models (IFMs) to generate RNA sequences that mirror natural evolutionary patterns while preserving the structural integrity of critical functional regions. Benchmarking 9 state-of-the-art genomic foundation models, we show that their unsupervised log-likelihood scores correlate strongly with RNA fitness, enabling zero-shot sequence design. Applied to fluorescent RNA aptamers, our approach yielded 20 Broccoli variants, over half of which achieved up to 155% in fluorescence and a twofold increase in binding affinity, with robust performance both in vitro and in vivo. For Pepper, two rounds of optimization produced 40 variants, 16 of which demonstrated up to 2.6 fold in fluorescence and a threefold boost in binding affinity, including five with superior in vivo brightness.This approach offers a scalable, efficient, and resource-light method for RNA design, with significant implications for RNA-based therapeutics and diagnostics. By leveraging general foundation models to facilitate RNA evolution in a zero-shot fashion, we believe our work represents a major advancement in the field of RNA engineering.

evolutionary biology↗

Enhanced Activity of Apramycin and Apramycin-Based Combinations Against Mycobacteroides abscessus

BackgroundMycobacteroides abscessus are rapidly growing non-tuberculous mycobacteria that cause chronic lung and soft tissue infections. Treatment options are often severely limited due to intrinsic resistance to most antimicrobials. Amikacin has historically been a mainstay of combination treatment regimens. However, irreversible hearing loss and vestibular toxicity have led to a search for alternative agents. Apramycin is a novel aminoglycoside currently in phase I clinical trials that may offer lower potential for ototoxic and renal toxic side effects. ObjectivesThe goal of this study was to compare apramycins in vitro activity with amikacin and other aminoglycosides against a large collection of M. abscessus clinical isolates, both alone and in combination with clofazimine or linezolid. We also tested the activity of apramycin against a more limited collection of other species of rapidly growing mycobacteria. MethodsAnalysis was performed using reference broth microdilution minimal inhibitory concentration testing, inkjet printer-assisted checkerboard assays, and time-kill assays. ResultsAgainst M. abscessus, the MIC50/90 for apramycin (2 {micro}g/mL) was 8-fold lower than for amikacin (16 {micro}g/mL). Plazomicin was inactive, and organisms were rarely susceptible to tobramycin. Synergy was not detected by checkerboard assay. In time-kill studies, clofazimine modestly potentiated activity of apramycin and. to a lesser extent, amikacin. Apramycin and amikacin showed delayed bacterial killing that either achieved or approached a bactericidal threshold. Apramycin was similarly potent against other rapidly growing mycobacteria tested. ConclusionsApramycin exhibits more potent in vitro activity against a diverse set of M. abscessus and other rapidly growing mycobacteria than approved aminoglycosides.

microbiology↗