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Hu, Z.

Publications and source records attributed to Hu, Z..

At least 55 records · Page 3Linked to original sources

A searchable metadata network graph for microbiome metabolomics

Establishing the biological context of microbial metabolites remains a major challenge. We present microbiomeMASST, a metadata-driven network graph that maps metabolites across 467 available datasets with 144,424 mass spectrometry files from humans, animals, and microbial culture systems. MicrobiomeMASST integrates monocultures, synthetic communities, and host-associated samples across multiple body sites and plants. MS/MS spectra can be queried to trace occurrence across hosts, experimental conditions, and interventions, enabling cross-study integration. We demonstrate this framework by contextualizing microbial-conjugated bile acids and interrogating microbiome-mediated drug metabolism. Screening gut bacteria revealed deprolylation of the angiotensin-converting enzyme (ACE) inhibitor prodrug enalapril. Using microbiomeMASST, we traced this metabolite across human cohorts, microbial isolates, environmental samples, and in Gorilla gorilla. Structural modeling and enzymatic assays showed that microbial deprolylation abolishes ACE inhibition, thereby inactivating its therapeutic effect. Together, microbiomeMASST links MS/MS spectra to biological context, converting isolated observations into an interpretable microbiome map for cross-study analysis.

biochemistry↗

A redox-regulated RCC1-like protein controls catalase activity in Arabidopsis

Reactive oxygen species (ROS) are central regulators of plant growth and stress responses. Cellular ROS levels are tightly controlled by antioxidant systems, including the evolutionarily conserved catalases that detoxify hydrogen peroxide (H2O2) predominantly within peroxisomes. Despite their importance, substantial gaps remain in our understanding of catalase biogenesis, regulation, subcellular targeting, and potential extra-peroxisomal functions. Using affinity purification of the UV-B photoreceptor UVR8 coupled with mass spectrometry, we identified a REGULATOR OF CHROMATIN CONDENSATION 1-like protein in Arabidopsis, which we named CATALASE-INTERACTING RCC1-LIKE 1 (CAIR1). CAIR1 interacts with all three catalase isoforms (CAT1-CAT3) as well as their chaperone NO CATALASE ACTIVITY 1 (NCA1). Loss-of-function cair1 mutants partially phenocopy cat2 and nca1, with reduced catalase activity, enhanced sensitivity to oxidative stress and alkaline growth conditions, and impaired primary root elongation. Mechanistically, cytosolic interaction between CAIR1 and CAT2 enhances total cellular catalase activity by facilitating peroxisomal import and proper subcellular localization of CAT2. In the absence of CAIR1, CAT2 forms aggregates, likely accounting for the observed loss of catalase activity. Notably, CAIR1 undergoes reversible, redox-dependent oligomerization that enhances its interaction with catalases. Mutation of CAIR1 at Cys-356 and Cys-545 compromises this interaction under elevated ROS conditions and fails to rescue the oxidative stress sensitivity of cair1 mutants. Moreover, UV-B exposure suppresses catalase activity by weakening the interaction between CAIR1 and catalases, thus linking environmental light signalling to cellular redox regulation. Together, our findings reveal CAIR1 as a dynamic redox-responsive regulator of catalase activity that maintains cellular redox homeostasis by coordinating catalase localization and function through reversible oligomerization.

plant biology↗

Functional In-Context Learning in Genomic Language Models with Nucleotide-Level Supervision and Genome Compression

AO_SCPLOWBSTRACTC_SCPLOWGenomic foundation models aim to learn general-purpose representations directly from DNA sequence, enabling sequence understanding, generation, and probabilistic reasoning across a wide range of biological tasks. Scaling such models to genomic lengths, however, remains challenging due to the tension between long-range context, nucleotide-level resolution, and practical computational efficiency. Architectural innovations have enabled increasingly long nominal inputs, but often struggle to translate additional context into meaningful performance gains, particularly in the presence of sparse functional signal along eukaryotic genomes. In this work, we revisit the design of long-context genomic foundation models from the perspective of training objective and data construction. We introduce Factorized Nucleotide Supervision (FNS), which reconciles efficient k-mer tokenization with single-nucleotide likelihoods through probability marginalization, and Genome Compression Pretraining (GCP), which reshapes the training distribution by concentrating on gene-centric and regulatory regions. Together, these techniques enable standard transformer-based models to perform functional in-context learning without sacrificing nucleotide-level fidelity or computational efficiency. Building on these ideas, we present a family of autoregressive genomic foundation models supporting contexts of up to 98k base pairs across eukaryotic and prokaryotic genomes. Across training-free evaluations and downstream fine-tuning benchmarks, our models consistently improve over prior approaches and match or exceed state-of-the-art baselines while enabling substantially more efficient inference. Together, these results demonstrate that aligning supervision and data regimes with the biological structure of genomic sequence provides a principled and effective path toward scalable and biologically faithful genomic language modeling. Models, data, and scripts for downstream analyses are publicly available at https://huggingface.co/GenerTeam.

genomics↗

Hidden causal inference delineates dynamic lncRNA regulation in autism spectrum disorder

Long non-coding RNAs (lncRNAs) are increasingly implicated in autism spectrum disorder (ASD), yet their causal regulatory mechanisms remain poorly characterized. Conventional static causal inference methods fail to capture the dynamic interplay of lncRNAs across diverse brain biological contexts. Here, we develop a hidden causality-based method Clean to infer dynamic lncRNA causal regulation in ASD. Our analysis reveals that dark causality, representing a hybrid form of positive and negative interdependencies, dominates lncRNA-mediated regulation in ASD. Moreover, dynamic lncRNA causal regulation emerges in diverse brain biological contexts, and 14 ASD risk lncRNAs significantly contribute to disease pathogenesis through disrupted gene regulatory programs. We also illustrate that lncRNA expression signatures enable robust classification of sex and cell type, offering potential diagnostic lncRNA biomarkers. Notably, 20 immune-related lncRNAs are prominently involved in the immune, suggesting a potential role for neuroimmune regulation. Additionally, cell-cell interaction networks diverge substantially between ASD and Normal cohorts. This study establishes a paradigm for delineating the dynamic causal regulation of lncRNAs, underscoring their diagnostic and therapeutic potential in ASD.

bioinformatics↗

Virtual prototyping of non-invasive spinal cord electrical stimulation targeting upper limb motor function

Transcutaneous spinal cord stimulation (tSCS) applied over the cervical or lumbar spinal cord facilitates motor function after paralysis. However, emerging electrophysiological evidence indicates mechanistic differences between cervical and lumbar tSCS and across different cervical tSCS paradigms. To clarify these discrepancies, we developed and validated a multi-scale, whole-body computational model of tSCS-induced volume conduction, axonal recruitment, and synaptic transmission. Across 24 cervical and four lumbar tSCS paradigms, simulations showed that somatosensory afferents consistently exhibit lower stimulation thresholds than motor efferents. In turn, region-specific synaptic transmission differences may explain electrophysiological discrepancies between cervical and lumbar tSCS. Across cervical tSCS paradigms, substantial volume conduction and axonal recruitment differences were observed that explain electrophysiological discrepancies. Specifically, clinically-prevalent paradigms, including those with anodes placed over the clavicles or iliac crests, engaged peripheral nerves in addition to spinal roots. This effect was amplified by multiphasic waveforms, which introduced recruitment sites near the anodes. By integrating simulations with electrophysiological recordings in 14 able-bodied individuals, we investigated previously unexplored cervical tSCS paradigms on their capacity to recruit somatosensory afferents relative to motor threshold.

neuroscience↗

Long-term Musculoskeletal and Marrow Sparing with Proton FLASH in Juvenile Mice: Implications for Pediatric Osteosarcoma

PurposeOsteosarcoma is the most common primary bone malignancy in children and adolescents. Radiotherapy is limited by intrinsic radioresistance and the risk of severe long-term musculoskeletal toxicities. FLASH radiotherapy, delivered at ultra-high dose rates (>40 Gy/s), has demonstrated normal tissue sparing in preclinical models, but its effects on the developing skeleton and marrow remain poorly defined. This study evaluated the chronic normal tissue effects of proton FLASH in juvenile mice, modeling the pediatric context. Methods and MaterialsJuvenile C57BL/6 mice (3-4 weeks old) were randomized to receive 11 Gy FLASH ({approx}200 Gy/s) or conventional proton irradiation (0.2 Gy/s average), or sham treatment to the left hind leg using a synchrotron-based proton beamline. Mice were followed for 10 weeks post-treatment. Bone toxicity was assessed with microCT (bone mineral density, bone volume fractions, trabecular indices) and histology. Bone marrow cellularity was quantified on H&E-stained sections, and muscle fibrosis was assessed using Massons trichrome. ResultsFLASH-treated mice exhibited significant preservation of bone microarchitecture compared with conventional treated mice, with higher bone mineral density and bone volume fractions (p < 0.05). Trabecular numbers were maintained, while structure model index indicates a mechanically favorable trabecular structures in the FLASH group. Bone marrow cellularity was preserved in FLASH mice (5.3% reduction vs. sham) compared with conventional (11.3 % reduction, p < 0.05). Muscle fibrosis was significantly lower in FLASH group (fibrosis positivity 2.6 % vs. 3.0% for FLASH vs. conventional CONV, p < 0.05). No severe immobility or weight loss was observed across groups. ConclusionsProton FLASH significantly reduces long-term bone, marrow, and muscle toxicities in juvenile mice. These findings provide the first demonstration of musculoskeletal sparing in a synchrotron proton FLASH platform and highlight its translational potential for pediatric osteosarcoma.

cancer biology↗

Pan-cancer silencer transcription atlas reveals leukemia silencer hijacking FOXP1 to enhance MYC oncogene

Numerous non-coding regulatory elements have been identified in the human genome. However, our understanding of silencers remains largely incomplete. Here, we proposed the concept of silencer transcriptional activity (STA) to investigated silencers from a new perspective using >20,000 transcriptomes. We demonstrated that lower STAs predicted better patient outcomes in most cancers, and a subset of STAs distinguished tumors from noncancerous tissues for most cancer types. Importantly, we discovered a silencer-linked RNA (slRNA) of a leukemia cell-specific silencer (LeSSi). Knocking down (KD) of the slRNA significantly decreased leukemia cell viability and migration and increased cellular apoptosis. Furthermore, the direct link and functional similarity between LeSSi and slRNA were established by CRISPR/Cas9 knocking out (KO) of LeSSi. Mechanistically, the slRNA hijacked FOXP1, which functions here both as a known transcription factor (TF), and more importantly, as a novel RNA binding protein (RBP), thereby preventing FOXP1 from binding to the promoter of proto-oncogene MYC and subsequently promoting MYC transcription. Collectively, our work provides insights into the functions of silencers in cancer and identified a slRNA hijacking FOXP1 to enhance MYC expression in leukemia cells.

genomics↗

Intermittent AP-1 activation in muscles contributes to exercise-induced health benefits

Regular physical exercise extends healthspan, yet the molecular mechanisms that translate intermittent contractile stress into lasting benefit remain incompletely understood. Using global nuclear run-on (GRO-seq) in mouse skeletal muscle after treadmill running, we profiled enhancer RNA (eRNA), a sensitive marker of enhancer activity. Activation protein-1 (AP-1), a family of pioneering factors for senescence, emerged as the top transcription factor with motif enrichment in exercise-activated enhancers. Our screen in the contracting C2C12 myotubes pinpointed cFos/JunD as the primary AP-1 factor responsible for contraction-induced transcriptional changes. Muscle-specific overexpression of A-Fos, a dominant-negative mutant of cFos, disrupted transcriptomic responses to exercise and attenuated exercise-mediated improvement in muscle functions. Interestingly, intermittent but not continuous overexpression of cFos/JunD in mouse muscles mimicked exercise-induced transcriptomic changes, increased mitochondrial volume density, enhanced muscle strength and fatigue resistance, and improved glucose tolerance. These results define a transcriptional regulatory signaling pathway linking exercise intermittency to beneficial adaptations and highlight the necessary recovery cycles in training. The paradoxical anti- and pro-aging roles of AP-1 offer insights into the timing and dynamics of stressors and stress responses in shaping senescence and healthspan.

molecular biology↗

DNA replication errors drive genome-wide small inverted triplication dynamics

Structural variants (SVs) have a profound impact on phenotype and diversity and are associated with human diseases. To explore the origination of SVs, we have analyzed 1,340 cancer genomes with annotation of 4,608 novel small inverted triplication (SIT) events and found that FEN1 is strongly associated with SIT incidence. Then, we performed long-read sequencing and developed PacBioR to annotate SITs in yeast FEN1 mutant cells. We found that SIT structures mimic classic inverted triplications but with a smaller DUP/IN/DUP structure of 184/160/184 bp on average, with a spacer sequence of 30 bp and breakpoint junction of 6 bp. We further showed that breakpoints of SITs preferentially occurred at nucleosome midpoints, aligned with Okazaki fragment termini, and those harbored in plasmids were precisely eliminated via DNA polymerase slippage over SIT-derived hairpin structures. This study provides mechanistic insight into SIT origination and offers practical tools for future studies on genome rearrangements.

genetics↗

The Immunogenicity Database Collaborative (IDC): A Standardized, Publicly Available Database for Clinical Immunogenicity Observations and Insights

The incidence and impact of anti-drug antibodies (ADAs) against biotherapeutics remain difficult to predict, limiting efforts to mitigate immunogenicity risk prior to clinical trials. Existing data are fragmented across disparate sources with inconsistent definitions, representing a key barrier to progress in the field. Here, we present the Immunogenicity Database Collaborative (IDC) and its release of the Immunogenicity Database (DB) V1: a structured clinical immunogenicity dataset integrating therapeutic characteristics, sequence, and patient cohort-level data from publicly available sources. The dataset includes 4,146 ADA datapoints, 1,788 cohorts, 727 clinical trials and 218 therapeutics. We highlight trends in ADA incidence, evaluate sources of variability, and identify driving factors of immunogenicity risk. This work provides a foundational resource to standardize and support immunogenicity risk assessment across the industry. It also provides an initial data architecture and invites the research community to contribute towards future expansions of the database into key areas of interest to the field.

pharmacology and toxicology↗

Decoding Neoantigen-encoding Tumor-Specific Transcripts Unveils a Shared Target Reservoir for Immunotherapy in Hepatocellular Carcinoma

Background and AimsPrimary liver cancer, predominantly hepatocellular carcinoma (HCC), has limited therapeutic options. While mutation-derived neoantigen vaccine holds promise, its success is hindered by low antigen availability. This study explores transcriptome-derived neoantigens (neoantigen-encoding tumor-specific transcripts, neoTSTs) in HCC, characterizing their features, generation mechanisms, and therapeutic potential. Approach and ResultsWe analyzed RNA-seq data from 1,013 liver cancer patients and constructed a multi-layered reference dataset. Using a customized pipeline, we identified an average of 60 neoTSTs per patient, significantly surpassing mutation-derived neoantigens (neoMuts). NeoTSTs exhibited higher population frequencies, with 73.1% providing multiple epitopes, and were validated through mass spectrometry and HLA transgenic mouse models. Mechanistically, neoTSTs were generated via retained introns, transposable element activation, HNF4A-regulated alternative promoters, and de novo transmembrane domain (TMD) generation. Single-cell analysis revealed neoTSTs cover >75% of tumor cells and identified antigen-presenting cancer-associated fibroblasts (apCAFs) that enriched in immunotherapy responders and amplified CD4 T-cell responses via MHC-II presentation. In murine HCC models, neoTST vaccination outperformed neoMuts, inducing dual MHC-I/II activation and significant tumor growth inhibition. ConclusionsNeoTSTs represent a superior neoantigen source in HCC, compensating for the limitations of mutation-derived targets. Their abundance, sharedness, and dual MHC pathway activation highlight their potential for personalized immunotherapy, particularly in low-TMB tumors. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=178 SRC="FIGDIR/small/692877v1_ufig1.gif" ALT="Figure 1"> View larger version (44K): org.highwire.dtl.DTLVardef@1bedfedorg.highwire.dtl.DTLVardef@5f6c95org.highwire.dtl.DTLVardef@d1deb5org.highwire.dtl.DTLVardef@743e85_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

RNA editing fine-tunes transcriptional plasticity and enhances the adaptability of Myzus persicae to diverse host plants

Parthenogenetic organisms can adapt to diverse and rapidly changing environments despite limited standing genetic variation, but the molecular mechanisms enabling such adaptability remain unclear. Here, we investigate this question in the green peach aphid (Myzus persicae, GPA), an asexual generalist herbivore capable of colonizing a wide range of host plants without underlying genetic change. By integrating RNA-seq and DNA-seq from genetically identical clones reared on different hosts, we identified 1,368 high-confidence RNA editing sites (RES), many of which exhibited strong host-dependent differences in editing levels. These RES encompassed all 12 possible nucleotide substitutions, with A-to-I, C-to-U, and U-to-C conversions being particularly prevalent. Editing at several sites shifted dynamically within 48 hours of host transfer and often coincided with changes in transcript abundance. Functional knockdown of the editing genes ADAR1 and ADAR2 reduced editing at specific sites, diminished fecundity, and abolished aphid survival on new hosts. Comparative analyses across aphid species reveal that although the biochemical signatures of A-to-I editing are deeply conserved, the genomic locations and functional roles of edited transcripts are species specific, reflecting lineage-specific adaptive strategies. Together, our findings demonstrate that RNA editing provides a rapid, reversible mechanism for environmental acclimation in GPA, enabling adaptive phenotypic plasticity even in the absence of genetic variation. This work establishes RNA editing as a key molecular basis for the remarkable ecological generalism of clonal organisms. Significance statementA major question in evolutionary biology is how clonal organisms with little genetic variation rapidly adapt to diverse, changing environments. Here we show that RNA editing provides a mechanism enabling the parthenogenetic green peach aphid (Myzus persicae) to colonize a wide range of host plants. RNA editing generates transcriptomic diversity, responds quickly to host shifts, and is essential for adaptation, as silencing ADAR genes disrupts A-to-I editing, reduces fitness, and prevents survival on new hosts. Comparative analyses across aphid species reveal that although the biochemical features of A-to-I editing are conserved, its genomic deployment and functional outcomes differ among species, reflecting lineage-specific strategies. These findings demonstrate that RNA editing creates a dynamic regulatory layer that offsets constraints of asexual reproduction.

molecular biology↗

An ancient transcription factor functions as the master regulator of primary cilia formation

How ancient transcription factors are repurposed during evolution to drive the functional diversification of conserved organelles remains a fundamental question in biology. Although highly conserved in basic morphology, eukaryotic cilia vary extensively in their sizes and functions. Previously, we showed that an evolutionarily ancient transcription factor, X chromosome-associated protein 5 (Xap5), controls motile ciliogenic transcriptional programs during mouse spermatogenesis (Wang et al., 2025). Here we show that Xap5 functions as the master regulator of primary ciliogenesis. Xap5 associates with the nuclear protein Non-POU domain-containing octamer-binding protein (Nono) to form a regulatory module that directly binds and activates the transcription factors Sox5 and Sox9. Genetic ablation of Xap5 or Nono impairs primary ciliogenesis, and loss of Sox5 disrupts the downstream ciliogenic program, consistent with the established role of Sox9. Collectively, our results provide new insight into how complex ciliary transcription factor networks determine ciliary diversity during evolution, and suggest that defects in this regulatory axis may contribute to the etiology of human ciliopathies.

cell biology↗

Charting the Undiscovered Metabolome with Synthetic Multiplexing

Most molecular features detected in untargeted metabolomics remain uncharacterized due to the limited scope of existing spectral reference libraries. We synthesized >100,000 biologically inspired compounds using multiplexed reactions, of which 91% were absent from existing structural databases, and searched the resulting MS/MS library across >1.7 billion public spectra, increasing annotation rates by 17.4%. This approach revealed previously undescribed exposure-derived metabolites, including ibuprofen-carnitine. Because ibuprofen has been linked to rhabdomyolysis, reduced mitochondrial function, and impaired muscle recovery in carnitine-limited contexts, we investigated the functional relevance of this conjugate. Ibuprofen-carnitine reduced carnitine transport via the OCTN2 transporter, and in a postpartum mouse muscle injury model, ibuprofen delayed muscle repair that could be rescued by carnitine supplementation, with urinary ibuprofen-carnitine:carnitine ratios tracking this effect. These findings support a hypothesis whereby NSAID-carnitine conjugates compete for carnitine transport, impairing energy metabolism and muscle recovery in susceptible individuals. Synthetic multiplexing thus provides a scalable route to annotate the dark metabolome and generate experimentally testable biological hypotheses.

biochemistry↗

Inherited retinal degenerations: PARP regulates calpain activation via TRPM2 channels in rd1 mouse photoreceptors

Inherited retinal degeneration (IRD) refers to untreatable blinding diseases characterized by progressive photoreceptor loss. Photoreceptor degeneration is often associated with an excessive activation of poly (ADP-ribose) polymerase (PARP) and Ca2+-dependent calpain-type proteases. To explore the interplay between PARP and calpain activity, we employed organotypic retinal explant cultures derived from wild-type mice and from the rd1 mouse model for IRD. Retinae were treated with the PARP inhibitors INO1001 or Olaparib, the poly (ADP-ribose) glycohydrolase (PARG) inhibitor JA2131, or the transient receptor potential channel M2 (TRPM2) blocker 8-Br-ADPR. Readouts included the TUNEL assay to detect cell death, in situ activity assays for histone-deacetylases (HDAC), PARP, and calpain, as well as immunostaining for activated calpain-2, and poly (ADP-ribose) (PAR). PARP, PARG, and TRPM2 inhibition reduced calpain activity and calpain-2 activation. PARP activity was decreased by PARP and TRPM2 inhibitors but not by PARG inhibition. Remarkably, the PARP inhibitor INO1001 increased HDAC activity unlike any of the other compounds. When combined with the PARG inhibitor JA2131, INO1001 reduced photoreceptor cell death in a synergistic fashion, although such synergy was not observed for calpain or PARP activity. Moreover, synergistic photoreceptor preservation was not observed when JA2131 was combined with the PARP inhibitor Olaparib. Overall, these results indicate that in rd1 photoreceptors, PARP controls calpain activity via PARG and TRPM2-induced Ca2+ influx. We also characterize INO1001 as potentially more beneficial for IRD treatment than Olaparib. Our study details the complexity of PARP-signalling in photoreceptors and identifies PARG and TRPM2 as new targets for IRD therapy development.

neuroscience↗

Systems analysis uncovers early temozolomide responses and peptide antigens in glioblastoma

Temozolomide (TMZ) is the standard treatment for nearly all glioblastoma (GBM) patients, as it is the only chemotherapy shown to extend overall survival. However, this benefit is limited to a few months, underscoring the need for combination strategies to improve its efficacy. While TMZ-induced DNA damage can both mediate cytotoxicity and promote resistance, DNA damage more broadly can also stimulate immune activation. To evaluate its immunomodulatory potential, we characterized the previously unexplored early, cell-intrinsic consequences of TMZ in GBM cells, spanning DNA damage, stress responses, and antigen presentation. A multi-omics approach combining RNA sequencing and quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) profiled changes in gene expression, nascent protein translation, steady-state protein levels, kinase-substrate phosphorylation patterns, and MHC-I peptide presentation in GBM cells within 72 hours of TMZ exposure. This analysis revealed rapid activation of DNA damage signaling and p53-associated stress pathways, alongside dynamic changes in protein synthesis and antigen presentation. A set of TMZ treatment-associated peptide antigens (TAPAs) was identified, including peptides derived from stress response proteins, phosphorylated MHC-I peptides, and those induced by other genotoxic treatments such as radiation. Several of these peptides were also detected in recurrent GBM patient tumors. Our findings suggest that TMZ not only triggers early adaptive and potentially resistance-associated stress programs but may also enhance the immune visibility of GBM cells. These data highlight potential windows for combination therapies with TMZ that bolster immune recognition of GBM, while the systems approach provides a framework to examine how genotoxic therapies across cancers alter tumor immunogenicity.

cancer biology↗

Scalable spike sorting across thousands of neurons by modeling neural dynamics with NeuroSort

Neural circuit research requires resolving the functional coding mechanisms at the single-neuron scale. However, neural signals captured from extracellular recordings are inherently complex, shaped both by electrode properties and the spatially distributed neural population activity across recording sites. These factors introduce strong signal mixing and waveform variation, making it diffcult for existing spike sorting methods to reliably isolate individual neurons from large-scale recodings. To address this, we develop NeuroSort, which fuses spatiotemporal information through a contrastive learning strategy to adaptively model neural dynamics. NeuroSort is a GPU-enabled, highly efficient spike sorting framework, enabling the isolating of up to thousands of neurons. We validated NeuroSort on in vivo extracellular recordings, including Utah array data from rhesus macaques performing motor tasks and Neuropixels 1.0 probe data from a rat during rest. Moreover, in a recording collected by the 1,024-channel Neuroscroll probe, NeuroSort sorted the largest number of well-isolated neurons from different brain areas while achieving a 2-8 times speedup over other methods. Taken together, NeuroSort generalizes across recording conditions, providing an interpretable and scalable paradigm for whole-brain dynamic analysis.

neuroscience↗

Suppression of hepatic amino acid catabolism by the human-specific lncRNA hLMR1

Amino acid (AA) catabolism and ureagenesis in the liver are essential for maintaining systemic nitrogen homeostasis. Patients with metabolic-associated fatty liver disease (MAFLD) exhibit impaired hepatic AA catabolism and urea production, accompanied by repression of genes governing these pathways. The molecular basis of this repression remains unknown. Here, we identify the hepatocyte-specific long noncoding RNA hLMR1 as a key suppressor of hepatic AA catabolism. Using a humanized liver mouse model, we show that hLMR1 knockdown broadly upregulates genes involved in AA degradation and ureagenesis. Chromatin isolation by RNA purification (ChIRP) coupled with RNA-seq reveals extensive interactions between hLMR1 and the pre-mRNAs of AA catabolism genes, mediated by a conserved complementary motif within hLMR1 (nucleotides 587-598). In primary human hepatocytes, hLMR1 overexpression inhibits glucagon-induced activation of AA catabolic genes, whereas deletion of the 587-598 region abrogates this effect. Analysis of human liver RNA-seq datasets demonstrates a negative correlation between hLMR1 expression and AA catabolic gene programs in MAFLD. Together, these findings uncover hLMR1 as a previously unrecognized regulator of hepatic nitrogen metabolism, linking lncRNA dysregulation to metabolic dysfunction in MAFLD.

molecular biology↗