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Liu, T.

Publications and source records attributed to Liu, T..

At least 73 records · Page 4Linked to original sources

Comprehensive long-read transcriptome analysis uncovers alternative RNA processing feature and isoform diversity in ovarian cancer progression

Post-transcriptional processing has a crucial yet largely unresolved dynamic change and role during the malignant progression of ovarian cancer, especially due to the limited read length of short-read RNA sequencing being insufficient to capture transcript diversity. Here, we performed Iso and RNA sequencing on paired normal, primary tumor, and metastatic samples, generating a comprehensive isoform atlas of over 41,000 full-length transcripts including many unannotated isoforms. Integrative analyses revealed extensive isoform-level remodeling across disease states that often occurred without concordant alterations at the gene level, emphasizing the importance of qualitative transcript regulation. Notably, we identified isoform-level alterations with distinct biological and clinical relevance, including differential expression of the short KRAS isoform, a tumor-specific isoform switch of TMEM201, and an alternative first-exon event in FNDC3B associated with poor survival. Together, these findings provide a high-resolution map of the ovarian cancer transcriptome and illustrate how long-read sequencing exposes multiple layers of post-transcriptional and clinical insight that remain hidden in conventional expression profiling.

bioinformatics↗

Grounding olfactory perception in language: Benchmarks and models for generating natural language odor descriptions

Recent advances in deep learning have enabled prediction of odorant perception from molecular structure, opening new avenues for odor classification. However, most existing models are limited to predicting percepts from fixed vocabularies and fail to capture the full richness of olfactory experience. Progress is further limited by the scarcity of large-scale olfactory datasets and the lack of standardized metrics for evaluating free-form natural-language odor descriptions. To address these challenges, we introduce Odor Description and Inference Evaluation Understudy (ODIEU), a benchmark which includes perceptual descriptions of over 10,000 molecules paired with a model-based metric for evaluating free-form odor text descriptions. The model-based metric uses Sentence-BERT (SBERT) models which are fine-tuned on olfactory descriptions to allow better evaluation of human-generated odor texts. Using the fine-tuned SBERT models, we show that free-form text odor descriptions contain additional perceptual information in their syntactic structure compared to semantic labels. We further introduce CIRANO (Chemical Information Recognition and Annotation Network for Odors), a transformer-based model that generates free-form odor descriptions directly from molecular structure, thus implementing the molecular structure-to-text (S2T) prediction. CIRANO achieves performance comparable to humans. Finally, we generate human-like descriptions from mouse olfactory bulb neural data using an invertible SBERT model, yielding neural-to-text (N2T) predictions highly aligned with human descriptions. Together, CIRANO and ODIEU establish a standardized framework for generating natural language olfactory descriptions and evaluating their alignment with human perception. Code is available at https://github.com/KoulakovLab/ODIEU

animal behavior and cognition↗

Myristoylation licenses disordered viral VP4 protein to anchor to and perforate the membrane through phase separation

The VP4 protein of enteroviruses, such as Coxsackievirus B3, is a small, intrinsically disordered protein essential for perforating the host cell membrane during viral entry. A key feature of VP4 is its N-terminal myristoylation, which is required for infectivity in some enteroviruses but dispensable in others, suggesting a complex and context-dependent role that is not fully understood. The precise biophysical mechanisms by which this lipid anchor enables a disordered protein to breach a membrane remain unresolved. Here, using Coxsackievirus B3 VP4 as a model system and integrating multi-scale molecular dynamics simulations with confocal microscopy, we demonstrate that myristoylation is not a simple membrane tether but a multi-functional regulator that orchestrates VP4 activity through distinct, hierarchical roles. First, it provides the necessary hydrophobic anchor to recruit the disordered VP4 to the membrane interface. Second, the myristoyl group acts as a key molecular driver that promotes the liquid-liquid phase separation of VP4, leading to the formation of dynamic condensates on the membrane surface. These condensates actively remodel the membrane, generating substantial curvature that, in turn, lowers the free energy barrier for VP4 penetration. Furthermore, we find evidence that the myristoyl group plays a third role in stabilizing the final transmembrane pore. Our findings establish a novel paradigm where a single lipid modification empowers a disordered viral protein to form a functionally potent condensate that mechanically primes and physically breaches the target membrane, a mechanism that may explain the conditional myristoylation requirement across enteroviruses.

biophysics↗

Not all mantra meditations are equal: Emergence of divergent alpha oscillatory dynamics across mantras

The study of contemplative practices has evolved into a mature field, yet current taxonomies tend to classify all mantra-based meditation approaches as a single category, overlooking potentially different neural states induced by different mantras or different instructions. To address this gap, we conducted a study of 50 novice subjects practicing two types of mantra-based meditation over a six week period to evaluate changes in Electroencephalography (EEG) during and after meditation. Participants were randomly assigned to meditating with the Hare Krishna (HK) and Sa-Ta-Na-Ma (SA) mantras. Using spectral parameterization, we assessed the effects of each type of meditation on individual alpha power (IAP), individual alpha frequency (IAF) and center of gravity (CoG). The results revealed marked differences in alpha dynamics between the two practices. On the one hand, the HK group exhibited widespread IAP decrease and an IAF/CoG increase during mantra meditation that was maintained during rest after the meditation, which became more pronounced after training in the HK meditation. On the other hand, the SA group showed a localized IAP reduction during meditation and significant reduction of IAF during meditation after training. We suggest that the higher cognitive demands of HK induce a more activating, attentionally focused state, whereas SA promotes a more relaxed state. Additional psychological data show that both meditation groups had reduction in stress. Thus, these findings challenge the monolithic classification of mantra meditation and highlight the importance of differentiating practices according to their mechanisms, particularly for their targeted application in mental health contexts.

neuroscience↗

Enhancing Patient Lymphocyte Response to Peritoneal Malignancies Using a Personalized Immunocompetent Microfluidic Co-Culture Platform

Harnessing patient immune cells via adoptive cellular therapy is a promising cancer therapeutic strategy. However, major challenges remain for advanced solid malignancies, including difficulty isolating sufficient tumor infiltrating lymphocytes (TILs) and limited targeting of diverse neoantigens in heterogenous tumors. To address this, we have developed a tumor-on-a-chip platform with co-cultured patient-derived tumor cells, autologous peripheral blood mononuclear cells (PBMCs), and lymphoid tissue-derived antigen presenting cells. This approach generates organoid interacting lymphocytes (OILs) with enhanced anti-tumor activity. In peritoneal malignancies, OIL-induced cytotoxicity of patient-matched tumor cells surpasses both TILs and static-expanded PBMCs. We find that this improved performance was linked to increased CD8+ T and NK cells among OILs, and increased effector cytokine polyfunctionality, particularly Granzyme A. Our platform represents a versatile and scalable approach to generate patient-specific therapeutic lymphocytes even when TILs are insufficient, offering a promising avenue to treat diverse solid tumors associated with poor outcomes under current immunotherapies. TeaserA tumor-on-a-chip device primes patient immune cells with tumor recognition for personalized immunotherapy applications.

cancer biology↗

Pharmacological recruitment of a VTA glutamatergic arousal circuit by the natural product BN3 drives broad-spectrum emergence from general anesthesia

Pharmacological control of emergence from general anesthesia remains strikingly limited. Clinically available antagonists are largely drug-class specific, leaving recovery dependent on anesthetic clearance rather than to an actively programmable switch in brain state. Through phenotypic screening of a structurally diverse natural-product library, we identified BN3 (L-(-)-camphor) as a broad-spectrum emergence agent. BN3 robustly shortened recovery from propofol anesthesia across species--from mice and rats to rabbits, dogs, and rhesus monkeys--and remained effective after continuous infusion. In rodents, BN3 also accelerated emergence from mechanistically distinct anesthetics, including etomidate, remimazolam, sodium {gamma} - hydroxybutyrate, midazolam, ketamine, sodium pentobarbital, and isoflurane. EEG recordings revealed a rapid cortical shift from slow-wave dominance to a wake-like high-frequency spectrum. Mechanistically, BN3 preferentially recruited ventral tegmental area (VTA) glutamatergic neurons: chemogenetic silencing abolished the BN3-evoked EEG spectral shift and strongly attenuated behavioral acceleration of emergence, whereas optogenetic activation of these neurons was sufficient to promote recovery. BN3 increased glutamate release in the nucleus accumbens and medial prefrontal cortex, and projection-specific inhibition of VTA[->]NAc or VTA[->]mPFC outputs blunted BN3-induced emergence. These findings define a VTA-centered glutamatergic arousal circuit that can be pharmacologically recruited as a common gateway for anesthetic-independent emergence.

neuroscience↗

Fully T2T pedigree assemblies reveal genetic stability and epigenetic plasticity of human centromeres across inheritance and cell-fate transitions

Centromeres are essential chromosome components yet remain poorly understood due to their highly repetitive sequence architecture. Using fully-phased telomere-to-telomere diploid assemblies from a three-generation pedigree integrated with long-read epigenomes from matched peripheral blood mononuclear cells, induced pluripotent stem cells, and neural progenitor cells, we generate allele-resolved single basepair resolution maps of centromere genetic and epigenetic dynamics across inheritance, reprogramming, and differentiation. We show that centromeric dip regions (CDRs), which define the functional core of centromeres, are positionally stable across generations and cell-fate transitions. In contrast, CDR epigenetic architecture is highly dynamic. Reprogramming markedly attenuates CDR hypomethylation, which is partially restored during differentiation in parallel with global hypomethylation of active alpha-satellite arrays and coordinated changes in nucleosome organization and protein occupancy. Centromeric remodeling is insulated from X-chromosome status, including Xa, Xi, and erosion. Finally, de novo mutations arising during reprogramming are enriched in centromeric regions but depleted within functional centromeric cores.

genomics↗

A structurally unique effector shared between Verticillium dahliae and Fusarium oxysporum is involved in cotton defoliation and virulence on other hosts

Defoliating (D) strains of the vascular wilt fungus Verticillium dahliae cause severe yield losses in cotton and olive worldwide, yet the genetic basis underlying this pathotype has remained unknown. Here, we combined comparative genomics, functional genetics, structural analysis, and phylogenomics to uncover the molecular determinant of defoliation. We identified a small, D pathotype-specific genomic region encoding two duplicated secreted effector genes. Simultaneous deletion of both gene copies abolished pathogenicity and defoliation in cotton, olive, Nicotiana benthamiana, and Arabidopsis thaliana, whereas single deletions reduced virulence and genetic complementation restored disease symptoms. Conversely, expression of the D effector in non-defoliating strains was sufficient to induce defoliation. Moreover, or exogenous application of the purified protein, induced wilting and defoliation as well. Structural analyses revealed that D homologs share a conserved but previously uncharacterized protein fold and are distributed across Verticillium and Fusarium species, exhibiting functional diversification and host-specific activity. Phylogenomic and genomic context analyses indicate repeated horizontal transfer events mediated by giant transposable elements known as Starships. Together, our findings identify the D effector as a central pathogenicity factor that drives defoliation and virulence, and demonstrate how Starship-mediated horizontal gene transfer shapes the emergence and dissemination of an agriculturally devastating fungal trait.

plant biology↗

Recovery of an 18th Century Rhinovirus Genome through Ancient RNA Isolation of Human Lungs

RNA viruses cause substantial global morbidity, yet their impact prior to the twentieth century remains obscured. While ancient DNA studies have transformed our understanding of past pathogens, ancient RNA (aRNA) isolation is largely restricted to exceptionally preserved samples. Here, we simultaneously recover aDNA and aRNA from non-formalin-fixed human lung specimens and reconstructed an 18th-century Human Rhinovirus (HRV) A genome--the oldest human RNA virus identified to date. The RNA is highly fragmented, with distinctive terminal misincorporations and coverage patterns consistent with double-stranded RNA. Phylogenetic analyses indicate that this historical HRV genome is an extinct lineage related to contemporary genotypes, providing a unique perspective on rhinovirus evolution. These findings demonstrate that centuries-old medical specimens can retain informative aRNA, expanding the temporal scope of paleovirology.

genomics↗

An Integrated Single-Cell and Epigenomic Resource for Comparative Analysis of the Basal Ganglia

The basal ganglia regulate motor, cognitive, and affective behaviors, and their dysfunction underlies diverse neurological and psychiatric disorders. Comprehensive, accessible multi-omics resources are needed to understand the regulatory mechanisms governing basal ganglia cell types. Here we present an open, interactive web-based platform for exploring single-cell multi-omics datasets from basal ganglia, generated using 10X Multiome, snm3C-seq, and Paired-Tag technologies from the BICAN (NIH BRAIN Initiative Cell Atlas Network) consortium. The platform is available at https://basalganglia.epigenomes.net/ and enables integrated visualization of gene expression, chromatin accessibility, DNA methylation, histone modifications, and chromatin conformation across cell types and human, macaque, marmoset, and mouse species, with direct genome browser support and comparative epigenomic functionality. Representative analyses demonstrate cell-type-specific regulatory landscapes, conserved and species-specific regulatory elements, and links between epigenomic regulation and transcription. This resource provides a scalable, community-oriented foundation for advancing basal ganglia biology and interpreting regulatory mechanisms relevant to brain function and disease. HighlightsO_LIIntegrated single-cell epigenomic resource for basal ganglia C_LIO_LIInteractive genome browser enables multi-omics and cross-species exploration C_LIO_LIReveals cell-type-specific and species-specific regulatory landscapes C_LIO_LISupports community access to complex brain epigenomic datasets C_LI

genomics↗

Prime-InDel version 1: A web tool providing InDel markers for targeted regions narrowing

While high-density SNP genotyping enables genome-wide assays in rice (Oryza sativa L.) and other crops, PCR-based markers--particularly those derived from insertion-deletion (InDel) variations--remain crucial for fine-mapping. Currently, readily available primer information for high-density InDel rice markers is still limited. We present the first version of PrimeInDel (https://rfgb.rmbreeding.cn/search/variation/primeIndel), an online tool integrating three sets of InDel markers: an 8K-set and a 316K-set from the 3K Rice Genomes (3K-RG) project, and a 22K-set compiled from published literatures. In user cases, primers from PrimeInDel proved highly effective, narrowing a cold-tolerance QTL (qSR2) from 2.7 Mb to 200 kb and a heading-date QTL (qDeh1.1) from 239.5 kb to 83.6 kb. Our work provides the community with a robust, PCR-based InDel primer, accessible via an online data set, which will facilitate germplasm genotyping and gene identification in rice breeding.

plant biology↗

OSTM1 is a ubiquitin E3 ligase that suppresses B-cell malignancy by activating the cAMP/PKA/CREB pathway

Osteoclastogenesis-associated transmembrane protein 1 (OSTM1) is a glycosylated, membrane-integral protein that regulates lysosomal homeostasis, with loss-of-function mutations causing autosomal recessive osteopetrosis. Through a whole-genome CRISPR/Cas9 screen, we identified OSTM1 as a previously unrecognized tumor suppressor in B-cell malignancies. Consistent with this role, OSTM1 is frequently deleted or downregulated across a broad spectrum of human B-cell cancers. In mice, B-cell-specific monoallelic or biallelic ablation of Ostm1 cooperates with Cdkn2a loss to drive lymphomagenesis with near-complete penetrance. Mechanistically, we uncover a cytosolic, non-glycosylated fraction of OSTM1 that functions as a ubiquitin E3 ligase to promote proteasomal degradation of phosphodiesterase 3B (PDE3B). As PDE3B hydrolyzes cAMP and suppresses the tumor-protective PKA/CREB/CREBBP signaling axis, loss of OSTM1 leads to PDE3B stabilization, attenuation of cAMP signaling, and enhanced oncogenic transformation. Together, our findings establish OSTM1 as a critical suppressor of B-cell lymphomagenesis through regulation of the cAMP/PKA/CREB pathway.

cancer biology↗

Distinct CA1 inputs support shifts in neural dimensionality and memory resolution

Event-based memories may be encoded with high (e.g., episodic) or low (e.g., gist) mnemonic resolution. While the CA1 region of the hippocampus encodes events at both scales, it is unclear how such dual coding emerges. Consistent with theoretical predictions1,2, here we show that trisynaptic (from CA3) and monosynaptic (from the medial entorhinal cortex) projections to CA1 encode high- and low-resolution event-based memories, respectively. Recruitment of the trisynaptic pathway during contextual fear conditioning promotes feedforward inhibition of CA1 via activation of parvalbumin-positive (PV+) interneurons. This allows sparse encoding of event-based memories in high-dimensional neural states that support high-resolution contextual fear memories, where mice exhibit conditioned fear only in the training context and not similar contexts. Inhibiting this input during training reduces activation of CA1 PV+ interneurons and feedforward inhibition, shifting neural dynamics to low-dimensional states that support low-resolution contextual fear memories where mice freeze in the training context and similar contexts. These experiments identify a circuit-based mechanism that causally links the dimensionality of CA1 neural dynamics to mnemonic resolution.

neuroscience↗

A Bear-Specific Coding Exon in TMEM41B Is Associated with Cold Adaptation

AbstractBears exhibit an unusual form of hibernation in which core body temperature remains relatively high despite profound suppression of whole-body metabolism. How such a warm yet hypometabolic state is achieved remains poorly understood. Here, through integrative analysis of 238 RNA-seq datasets spanning seven species, we identify transmembrane protein 41B (TMEM41B) as an evolutionarily conserved factor associated with thermogenic capacity. Loss of Tmem41b in mice and Drosophila results in severe cold intolerance, whereas its overexpression enhances thermogenic performance, supporting a conserved role in heat production. Comparative genomic analyses reveal a bear-specific 51-amino acid N-terminal extension in TMEM41B, arising from a 5' untranslated region mutation that converts a premature stop codon into coding sequence. Interactome profiling indicates that this bear-specific isoform differs from the canonical TMEM41B in its protein interaction landscape, including reduced association with components of mitochondria-associated endoplasmic reticulum membranes such as voltage-dependent anion-selective channel protein 1 (VDAC1). Consistent with this altered interaction profile, the extended isoform is associated with reduced mitochondrial oxidative activity. Functional analyses further suggest that the 51- amino acid extension modulates multiple cellular programs, including suppression of oxidative phosphorylation and myogenic differentiation alongside activation of osteogenic pathways, collectively biasing cells toward a hypometabolic state. Notably, expression of the polar bear TMEM41B isoform in mice induces a torpor-like phenotype under fasting conditions. Together, these findings identify TMEM41B as a conserved regulator of thermogenic capacity and suggest that evolutionary modification of its N terminus may contribute to metabolic suppression and energy conservation during bear hibernation.

evolutionary biology↗

Protein-peptide Interaction Representation Learning with Pretrained Language Models

Protein-peptide Interactions (PpIs) paly essential roles in diverse cellular processes, yet their systematic identification remains challenging due to the limited availability of experimentally annotated protein-peptide interaction data. To address this challenge, we present PepInter, a sequence-based Deep Learning (DL) framework that leverages large-scale pretraining on structurally derived pseudo protein-peptide pairs to learn interaction-relevant representations. Specifically, energy-dominant peptide fragments are extracted from protein complexes curated from non-redundant Protein Data Bank (PDB) structures, enabling the construction of pseudo protein-peptide interaction pairs that capture interface interaction patterns shared with canonical protein-protein interactions. This strategy allows the model to acquire interaction-aware priors in the absence of large-scale annotated protein-peptide complex datasets. Built upon the ESM-Cambrian (ESMC) architecture, PepInter adopts a two-stage pretraining strategy. In the first stage, masked language modeling is used to learn general protein sequence representations. In the second stage, the model is further trained to predict Rosetta-derived energetic scores, explicitly incorporating structural interaction signals into the learned embeddings. Following pretraining, PepInter is fine-tuned for both protein-peptide interaction classification and peptide bioactivity regression tasks. Across multiple benchmark datasets, including protein-peptide binding affinity prediction, PepInter consistently outperforms existing baseline methods and demonstrates strong generalization in identifying biologically meaningful PpIs. Case studies further highlight its ability to recover known interaction patterns and predict novel protein-peptide interactions. Together, these results establish PepInter as a scalable and effective framework for protein-peptide interaction prediction, with strong potential to accelerate peptide-based drug discovery.

bioinformatics↗

MYST acetyltransferases are a targetable therapeutic vulnerability in SETBP1-mutant leukemia

Mutations in SET binding protein 1 (SETBP1) are associated with an adverse prognosis in myeloid malignancies. These mutations stabilize SETBP1 protein, driving increased expression of a progenitor-associated gene expression program through incompletely described mechanisms. A proteomic screen revealed interactions between SETBP1 and members of the MYST acetyltransferase complexes, including the catalytic subunits--KAT6A and KAT7. Mutant SETBP1 increases the localization of MYST complexes at known SETBP1 target genes, including the Hoxa cluster, where it drives increased histone acetylation and gene expression. Treatment of SETBP1D868N-expressing myeloid progenitors with MYST inhibitors reduced target gene expression. To establish the efficacy of MYST inhibition in vivo, we treated mice harboring a syngeneic SETBP1-mutant leukemia with the clinical-grade MYST inhibitor--PF-9363. This resulted in complete hematologic control and increased survival. MYST inhibition was also highly effective against a SETBP1-mutant PDX model. These studies identify MYST acetyltransferases as promising therapeutic targets in SETBP1-mutant malignancies. Statement of SignificanceSETBP1 mutations are markers of high-risk myeloid malignancies, but we lack any targeted therapies to improve outcomes. In this study, we identify MYST acetyltransferases as key drivers of mutant SETBP1-driven transcription. MYST inhibitors are highly effective against SETBP1-mutant leukemia and represent a promising avenue for clinical translation.

cancer biology↗

3'to 5'translation of linear mRNAs?

3[->]5 translation (termed "backward translation") mediated by eukaryotic circular RNAs has been reported recently. Whether linear mRNA can produce proteins through backward translation remained elusive. Here, we demonstrate that linear mRNAs can mediate backward translation in vitro. Backward translation was detected in human cells transfected with expression vectors used to produce linear mRNAs. Importantly, synthetic linear mRNAs could produce backward translation signal in multiple in vitro translation systems, with a level comparable to that of conventional 5 to 3 forward translation. Furthermore, we demonstrated that a single translation initiating sequence (TIS) was able to drive backward and forward translation in an in vitro experimental setup, with the efficiency of backward translation found to be significant lower than that of forward translation. In summary, this study further reinforces the notion of translation flexibility, demonstrates a broader applicability of backward translation and heralds a new strategy in synthetic biology.

cell biology↗

Cell type diversification and phenotype convergence underlying white fin-ornamentation of cyprinid fishes

Neural crest derived cells offer valuable opportunities to dissect mechanisms of cell fate specification and differentiation within individual ontogenies and the underpinnings of cell type diversification over evolutionary time. Particularly useful for such analyses are pigment cells of ectothermic vertebrates that arise from neural crest cells, or via latent neural crest derived stem cells, and comprise several classes with cell-type specific pigmentary phenotypes. Among these are white cells, "leucophores," present in a variety of species that contribute to patterns on the body or ornamentation on the fins. To better understand developmental and evolutionary origins of these cells we have examined leucophores harboring deposits of yellow/orange carotenoids, "xantholeucophores," of zebrafish and leucophores of white cloud minnow, within the same family Cyprinidae. We show that white phenotypes of both cell types require sepiapterin reductase that promotes accumulation of pale and colorless pteridines. We further demonstrate that xantholeucophores develop directly from yellow sepiapterin rich xanthophore-like cells and that this transition requires both gap junctional activity and permeability of the aquaglyceroporin / peroxiporin channel Aquaporin 3. These findings identify these white cells as distinct developmentally, genetically, and biochemically from another type of white cell in zebrafish and other white cells present across phylogenetic lineages. Our results highlight remarkable convergences and parallelisms in the acquisition of white cell phenotypes within and between species and identify this as a rich system for enquiries into the evolutionary individuation of novel cell types. SignificanceUnderstanding how cell types arise is fundamental to explaining animal complexity. Pigment cells offer opportunities to address this question because they display striking variation. We show that white pigment cells comprise multiple classes with independent origins. In zebrafish, white cells on one fin develop from melanophores whereas white cells on another fin develop from yellow precursors that convert their pigments to colorless ones. White cells of a related minnow require the same colorless pigments yet differ in other ways. These findings illuminate remarkable convergence: white cells have arisen repeatedly from different progenitor cell lineages by different mechanisms. This diversity--even within and between closely related species--identifies a powerful model for understanding the evolution of cell types with distinct identities and functions.

developmental biology↗