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Biology subjects

Cui, H.

Publications and source records attributed to Cui, H..

At least 37 records · Page 2Linked to original sources

p53 preserves genome stability in dividing cells under hypo-osmotic stress

Cells respond to frequent osmotic stress to maintain structural integrity and function. Whereas acute volume regulation is well-known, the cellular response to prolonged osmotic stress and its long-term consequences remain poorly understood. In this study, we investigate how lasting hypo-osmotic stress influences cell growth and division and the associated cellular response. We observe that cells undergoing their first division under hypo-osmotic stress experience delayed mitotic entry, lengthened mitotic duration, elevated mitotic errors and aneuploidy formation. However, continued cell division is halted through a p53/p21-dependent G1 arrest. p53 activation occurs post-mitotically and is associated with hyper-condensed chromatin and impaired nuclear expansion in daughter cells after mitotic exit. We show that the altered nuclear size dynamics lead to nuclear accumulation of p53 and activation of downstream gene expression. These findings uncover a mechanosensitive, p53-mediated mechanism that safeguards genome integrity by suppressing erroneous mitosis under hypo-osmotic stress.

cell biology↗

Concurrent saliency and intentional maps in posterior parietal cortex

AbstractThe goal for motor action represents the desired state of the individual when interacting with the world. Investigating how the goal is generated requires clarifying spatial extrapolation that involves perceptual and action processes. Here, we recorded neural activity from monkeys manually intercepting a circularly moving target being occluded. The saliency and intentional maps, which developed to locate the target of interest and the intended action goal, were thus distinguished in neural activity recorded from the lateral intraparietal cortex (LIP) and parietal reach region (PRR). Dynamic internal representations spanning from visual registration to state estimation were unveiled in both areas, with the goal for the interception being inferred as the visual consequence of the movement. The motion extrapolation was found to be an intrinsic part of movement planning, so that the continuous and stable spatial extrapolation from motion to action was prevalent in both areas. The goal estimation based on the sensory extrapolation rationalized the concurrency and correlation of saliency and intentional maps, which were found to switch their dominance by reorganizing the read-out dimensions of the spatial manifold. The extrapolation achieved at both the perceptual and motor stages not only bridged the saliency and intentional maps, but also revealed the form of the state estimation in guiding predictive sensorimotor control.

neuroscience↗

Preserved Neural Dynamics across Arm- and Brain-controlled Movements

The neural activity for motor control is complex and dynamic; it has been found to dramatically transit from planning to executing movements. As brain-machine interfaces (BMIs) can directly connect the brain and the external world by yielding comparable motor outcomes with artificial apparatus, a central question is whether the BMI-controlled movements share neural dynamics or underlying mechanism with natural movements. To enable a systematic comparison, we developed a feedforward BMI framework with distinct planning and executing epochs that enables ballistic cursor control to intercept moving targets. This BMI allowed monkeys to voluntarily initiate neural states which controlled the direction and timing to launch a ballistic movement, like skeet shooting. Based on this, we found similar neural representations and computational structures across arm- and brain-controlled conditions. Notably, in addition to resembling the rotational structure in natural reaching, the neural population dynamics during open-loop BMI also shared preserved manifolds with those during reaching arm movements. These findings suggest a fundamental principle, and reveal a set of basic computational motifs for the neural control of movement in an abstract hierarchy in the absence of constraints from actuators. This study thus has the potential to reshape the consideration of how BMIs assist paralyzed patients in interacting with dynamic environments, and to promote next-generation BMI systems.

neuroscience↗

Modular mRNA lipid nanoparticle platform rescues diverse genetic male infertility

Genetic male infertility arises from diverse mutations that disrupt spermatogenesis, yet therapeutic strategies capable of restoring germ-cell function remain limited. Messenger RNA (mRNA) therapeutics offer a programmable and non-integrating approach, but their functional compatibility in structured and immune-privileged tissues remains unclear. Here we identify a temporal mismatch between mRNA delivery kinetics and the progression of spermatogenesis as a key barrier to functional rescue. We show that delivery efficiency does not predict outcome: formulations with high peak expression but short duration fail to support spermiogenesis, whereas sustained expression aligned with developmental timing enables recovery. Guided by this principle, we establish a testis-targeted mRNA delivery platform that restores spermatogenesis across multiple genetic models and generates functional sperm capable of supporting embryo development and multigenerational inheritance. The approach is modular, extends to human seminiferous tubules ex vivo, and is supported by comprehensive safety analyses. Together, these findings define a design constraint for RNA therapeutics in structured tissues: functional rescue requires temporal alignment between delivery kinetics and the therapeutic window defined by tissue-specific biological programs.

bioengineering↗

Carbohydrate adaptation drives liver-brain axis maturation

Mammalian postnatal life requires adaptation to a carbohydrate-rich diet, yet how metabolic programs are coordinated within and across organs is unclear. Using time-resolved transcriptomic and metabolomic analyses from the neonatal period through adulthood, we show that mouse liver rapidly acquires oxidative and detoxification capacity after weaning. This transition enables the brain to establish energy-sufficient, low-toxicity metabolic environment for neuronal development. This maturation process is marked by progressive activation of the hepatic electron transport chain (ETC), with the mitochondrial RNA endoribonuclease LACTB2 acting as a key regulator. LACTB2 prevents the accumulation of mitochondrial RNAs and sustains expression of mtDNA-encoded ETC subunits, thereby preserving mitochondrial competence for oxidative metabolism. LACTB2 is postnatally induced in hepatocytes, and its loss causes defective glucose utilization, systemic metabolic toxicity, and impaired brain metabolism and myelination, leading to prepubertal lethality, particularly in males. Restoring ETC function through liver-targeted expression of yeast NADH dehydrogenase NDI1, inhibiting the integrated stress response or ammonia scavenging improved survival. Our findings identify LACTB2-dependent hepatic mitochondrial maturation as a central mechanism that aligns carbohydrate adaptation with the liver-brain metabolic coordination to support early-life development.

developmental biology↗

Adjacent Rare-Earth Separation via a Protein Atomic Ruler

The separation of rare-earth elements (REEs) poses a formidable challenge due to their nearly identical ionic radii and chemical properties. Here, we present a transformative strategy for REE separation using a multimetal ion-stacking metalloprotein framework (MIF) that functions as an atomic ruler, effectively amplifying subtle differences in REE ionic radii. This approach achieves exceptional selectivity, enabling the separation of all 13 adjacent REE pairs with ultrahigh purity (up to 99.999%). Remarkably, the MIF retains its lanthanide-binding capacity over 410 consecutive absorption-desorption cycles, demonstrating outstanding stability. Structural insights reveal that the MIFs densely packed REE coordination environment magnifies minute radius variations--a key mechanism underlying its unparalleled separation efficiency. Our MIF-based strategy offers a sustainable, scalable solution to rare-earth separation in industrial applications.

biophysics↗

Agro-STARR-seq enables in planta genome-wide enhancer discovery and AI-empowerd enhancer design

Comprehensive enhancer screening is essential for dissecting gene regulatory networks. However, methods for such screening remain limited in plants. We present Agro-STARR-seq, an in planta enhancer screening platform using Agrobacterium-mediated delivery of STARR-seq libraries into Nicotiana benthamiana leaves. In the Arabidopsis genome, we identified 14,715 sequences with enhancer activity, of which 91.59% were located outside of open chromatin regions. This largest in planta enhancer dataset to date enabled AI-assisted design of highly active synthetic enhancers. For the large N. benthamiana genome, we pre-processed the genomic DNA with an Assay for Transposase Accessible Chromatin (ATAC) procedure before the Agro-STARR-seq protocol,and found that only one-third of open chromatin exhibited enhancer activity, 76.00% of which showed no canonical H3K27ac histone marks. Footprinting analysis further enables systematic linkage of transcription factor (TF) binding to enhancer function. Overall, Agro-STARR-seq provides a novel platform for dissecting and engineering plant enhancers.

genomics↗

Sialoglycans on human T cells attenuate death programs executed through the Fas pathway

T cells are critical executors of adaptive immune responses and their persistence is tightly regulated. Part of this regulation relies on programmed cell death driven by the Tumor Necrosis Factor (TNF) receptor superfamily. The addition of glycans that terminate in the monosaccharide sialic acid (sialoglycans) to these cell death receptors has been shown to attenuate their apoptotic functions. While this is now understood to be a pro-survival mechanism in settings of cancer pathophysiology, the specific roles of sialoglycans in regulating cell death receptor activity on human T cells remains unexplored. This is of particular importance given the rising interest in T cell glycan editing for therapeutic benefit. Here, we address this gap using both immortalized (Jurkat) and primary human T cells deficient in sialoglycans. We found that T cell sialoglycans suppressed apoptosis induced by the Fas receptor (FasR) but not other TNF receptor superfamily members such as TNFR1 and TRAIL-R1. Dynamic reorganization of FasR was increased on sialoglycan-deficient Jurkat cells, suggesting that these glycans limit receptor clustering. This model was further supported by phosphoproteomics results, which confirmed that loss of sialoglycans negatively regulated the pro-survival MAPK/ERK signalling pathway. Finally, we used a recombinant sialic acid cleaving enzyme (sialidase) to confirm that sialoglycans on primary human T cells are bona fide immunophysiological regulators of FasR-driven programmed cell death. Combined, our results demonstrate that sialoglycan remodelling on T cells influences cell fate driven by the Fas pathway and provide motivation to further characterize the immunoregulatory roles of the glycocalyx in health and disease.

immunology↗

A point mutation in the nuclear speckle protein and splicing factor SRRM2 is associated with amyotrophic lateral sclerosis and causes dysregulation of synapse-associated genes

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive loss of motor neuron function. ALS is a multifactorial disease which can originate from complex genetic and environmental factors. The identification of risk factors and their molecular contribution to ALS expand our understanding of the disease mechanism. Here, we describe a family with dominantly inherited degeneration, which carries a mutation in the serine/arginine repetitive matrix 2 gene (SRRM2). SRRM2 is essential for nuclear speckle formation and a constitutive member of the RNA splicing machinery. To investigate how the mutation in SRRM2 contributed to the ALS pathogenesis, we examined its effect on a model cell line, where the point mutation was introduced in the endogenous gene. Surprisingly, we found that the resulting single amino acid exchange led to the loss of one protein-protein interaction, between SRRM2 and the splicing factor ACIN1. Transcriptome studies further revealed wide-spread differential gene expression, which converged on the dysregulation of synapse-associated pathways. Together, our findings identify SRRM2 as a novel ALS risk factor and provide mechanistic insights into how its mutation can be linked to ALS pathology.

molecular biology↗

RARS1 integration into the multisynthetase complex is crucial for mammalian brain development

Aminoacyl tRNA synthetases occupy a central role in protein synthesis by charging tRNAs with their cognate amino acid. Eight aminoacyl-tRNA synthetases with nine enzymatic activities form a large protein complex but the breadth of functions mediated by the multisynthetase complex remains elusive. Neurological disorders have been associated with mutations within the domain tethering Arginyl-tRNA synthetase (RARS1) to the multisynthetase complex, which offers an interesting bridge between protein synthesis and neurodevelopment. To interrogate this connection, we developed a mouse model where RARS1 is excluded from the multisynthetase complex in the forebrain. We observed profound disruptions in neural development as attested by drastically reduced forebrain size and behavioral deficits. At the molecular level, neurodevelopmental and ribosomal genes were dysregulated. Finally, the subcellular localization of RARS1 and its colocalization with other translational machinery components were perturbed. Altogether, our results reveal the necessity of RARS1 integration in the multisynthetase complex for proper neurodevelopment.

molecular biology↗

Uncovering directionally and temporally variable genes with STAVAG

Spatially variable genes (SVGs) are crucial for understanding spatial heterogeneity in spatial transcriptomics. Yet, SVGs are challenging to align with established biological axes and lack straightforward mechanistic interpretation, thereby limiting their ability to inform downstream experiments or clinical applications. Here, we introduce the concept of directionally variable genes (DVGs) and temporally variable genes (TVGs). Also, we propose a unified framework, STAVAG, that models spatial or temporal information to identify DVGs and TVGs. STAVAG effectively identifies biologically meaningful DVGs for uncovering prognostically relevant gene modules that align with the malignant-immune-stroma structure in the tumor microenvironment, identifying marker genes in three-dimensional brain data, and detecting 12 polarization genes regulating planarian regeneration. Furthermore, by tracking the progression of myocardial infarction and tissue development, STAVAG reveals critical TVGs that can serve as diagnostic biomarkers for the ultra-acute phase of myocardial infarction. STAVAG also identifies both global and local gene modules involved in mouse placentation, as well as tissue-specific and interactive TVG modules that dynamically evolve during mouse embryonic development.

bioinformatics↗

A disease-causing Isoleucyl-tRNA synthetase variant leads to altered protein complex formation and cellular stress response

Aminoacyl-tRNA synthetases are key enzymes in protein synthesis, as they catalyze the attachment of amino acids to their designated, cognate tRNAs. As such, mutations in aminoacyl-tRNA synthetases are associated with severe diseases, such as neurodevelopmental disorders. Many of these mutations occur in the catalytically active site or tRNA binding domains, however, others can affect domains associated with multisynthetase complex formation. Here, we investigate a disease-causing mutation in the UNE-L domain of Isoleucyl-tRNA synthetase (IARS1, IleRS), which mediates IleRS interactions within the multisynthetase complex. Interestingly, levels of the resulting protein were severely reduced in comparison to wildtype IleRS. While bulk protein synthesis and cell proliferation were not affected, the integrated stress response signaling pathway was altered. This change was exacerbated in low glucose medium, suggesting that mutant cells could respond differently to cellular stress. Our study hints at a possible underlying disease mechanism, where catalytic activity might not be affected but instead complex formation and protein stability.

molecular biology↗

Dysregulated nuclear Lamin B1 in DYT1 dystonia thickens the nuclear lamina and disrupts 14-3-3 proteins

Childhood-onset DYT1 dystonia is caused by a heterozygous {Delta}E mutation in the TOR1A gene, which encodes a membrane-embedded AAA+ (ATPase Associated with diverse cellular Activities) ATPase. However, the mechanism by which {Delta}E induces dystonia remains poorly understood. Previously, using patient-derived neurons, we identified dysregulation of nuclear Lamin B1, at both expression levels and subcellular distribution, as a key contributor to DYT1 pathology. In the present study, we utilized DYT1 patient fibroblast cells and induced human neurons to investigate the molecular basis and consequences of Lamin B1 dysregulation. We found that elevated nuclear Lamin B1 thickens the nuclear lamina and deforms the nucleus, impairing nucleocytoplasmic transport. Proteomic analysis of human iPSC-derived neurons revealed that mislocalized Lamin B1 disrupts essential signaling pathways involved in neuronal function. Notably, 14-3-3 proteins, abundant brain molecular chaperones critical for neuronal development and homeostasis, were the most strongly associated with mislocalized Lamin B1. Functional studies showed that downregulation of 14-3-3 proteins impairs neurodevelopment in healthy neurons, while their upregulation rescues DYT1 neuronal defects by reducing Lamin B1 mislocalization. These findings elucidate a mechanistic link between nuclear deformation and cellular dysfunction in DYT1 dystonia and highlight Lamin B1 and 14-3-3 proteins as potential therapeutic targets.

neuroscience↗

Light-up nanostructures with allosteric DNA mimics of GFP

In this study, we present a systematic approach for the rational design of synthetic allosteric DNA aptamers. This methodology enables precise control over the allosteric ON-OFF transition in fluorescent DNA aptamers, allowing for the engineering of aptamers with highly tunable fluorescent properties. When combined with toehold-mediated strand displacement, we have developed a series of allosteric aptamers in which the target sequence functions as a specific allosteric modulator. Furthermore, these aptamers have been applied in synthetic DNA computing and in the construction of responsive nanostructures that light up upon activation.

synthetic biology↗

Speak or shout? Nonverbal vocalizations ensure rapid detection of emotions in vocal communication

Human vocal expressions of emotion can be expressed nonverbally, through vocalizations such as shouts or laughter, or speakers can embed emotional meanings in language by modifying their tone of voice ("prosody"). Is there evidence that nonverbal expressions promote "better" (i.e., more accurate, faster) recognition of emotions than speech, and what is the impact of language experience? Our study investigated these questions using a cross-cultural gating paradigm, in which Chinese and Arab listeners (n=25/group) judged the emotion communicated by acoustic events that varied in duration (200 milliseconds to the full expression) and form (vocalizations or prosody expressed in listeners native, second or foreign language). Accuracy was higher for vocalizations overall, but listeners were markedly more efficient to form stable categorical representations of the speakers emotion from vocalizations (M = 417ms) than native prosody (M = 765ms). Language experience enhanced recognition of emotional prosody expressed by native/ingroup speakers for some listeners (Chinese) but not all (Arab), emphasizing the dynamic interplay of socio-cultural factors and stimulus quality on prosody recognition which occurs over a more sustained time window. Our data show that vocalizations are functionally suited to build robust, rapid impressions of a speakers emotion state unconstrained by the listeners linguistic cultural background.

animal behavior and cognition↗

Structural basis for DNA double-strand break sensing by human MRE11-RAD50-NBS1 and its TRF2 complex

The MRE11-RAD50-NBS1 (MRN) complex is a central, multifunctional factor in the detection, signaling and nucleolytic processing of DNA double-strand breaks (DSBs). To clarify how human MRN binds generic and telomeric DNA ends and can separate DNA end sensing from nuclease activities, we determined cryo-electron microscopy structures of human MRN bound to DNA and to DNA and the telomere protection factor TRF2. MRN senses DSBs through a tight clamp-like sensing state with closed coiled-coil domains, but auto-inhibited MRE11 nuclease. NBS1 wraps around the MRE11 dimer, with NBS1s ATM recruitment motif sequestered by binding to the regulatory RAD50 S site, necessitating an allosteric switch for ATM activation. At telomeric DNA, TRF2 blocks the second S site via the iDDR motif to prevent nuclease and ATM activation. Our results provide a structural framework for topological DNA sensing and separation of sensing, signaling and processing activities of mammalian MRN. Highlights- Human MRN senses DNA ends with an autoinhibited nuclease - NBS1s C-terminus binds one RAD50 S site in the sensing state - TRF2 binds MRNs second S site at telomeres - RAD50 and ATM compete for the NBS1 C-terminus

biochemistry↗

HydraRNA: a hybrid architecture based full-length RNA language model

RNA, an essential component of the central dogma of molecular biology, plays versatile roles in all cellular processes. RNA large language models (LLMs) are emerging as powerful methods in RNA research to decipher its intricate network of function and regulation. However, previous RNA LLMs were based on the transformer model and pre-trained on short segment of non-coding RNAs, which limits their general usability. Here we present the first full-length RNA foundation model, HydraRNA, which is based on a hybrid architecture of bidirectional state space model and multi-head attention mechanism, and is pre-trained on a large amount of both protein-coding and non-coding RNAs. Despite being pre-trained with the fewest parameters and the least GPU resources, HydraRNA learns better RNA representations and outperforms the existing foundation models on a variety of downstream tasks, including RNA classification, prediction of RNA secondary structure, RBP binding sites, mRNA stability and translation efficiency. Furthermore, HydraRNA can accurately predict the effect of mutations and estimate the relative contributions of different mRNA regions to the RNA stability and translation. We anticipate that HydraRNA will enable dissecting the diverse properties of RNA, accelerating the research of RNA regulation and facilitating the optimal design of RNA therapeutics.

bioinformatics↗

Natural self-attenuation of pathogenic viruses by deleting the silencing suppressor coding sequence for long-term plant-virus coexistence

Potyviridae is the largest family of plant-infecting RNA viruses. All members of the family (potyvirids) have positive-sense single-stranded RNA genomes, with polyprotein processing as the main expression strategy. The 5-proximal regions of their genomes encode two types of leader proteases: the serine protease P1 and the cysteine protease HCPro. However, their arrangement and sequence composition vary greatly among genera or even species. The leader proteases play multiple important roles in different potyvirid-host combinations, including RNA silencing suppression and virus transmission. Here, we report that viruses in the genus Arepavirus, which encode two HCPro leader proteases in tandem (HCPro1-HCPro2), can naturally lose the coding sequences for these two proteins during infection. Notably, this loss is associated with a shift in foliage symptoms from severe necrosis to mild chlorosis or even asymptomatic infections. Further analysis revealed that the deleted region is flanked by two short repeated sequences in the parental isolates, suggesting that recombination during virus replication likely drives this genomic deletion. Reverse genetic approaches confirmed that the loss of leader proteases weakens RNA silencing suppression and other critical functions. A field survey of areca palm trees displaying varied symptom severity identified a transitional stage in which full-length viruses and deletion mutants coexist in the same tree. Based on these findings, we propose a scenario in which full-length isolates drive robust infections and facilitate plant-to-plant transmission, eventually giving rise to leader protease-less variants that mitigate excessive damage to host trees, allowing long-term coexistence with the perennial host. To our knowledge, this is the first report of potyvirid self-attenuation via coding sequence loss. Author summaryPlant viruses typically persist throughout the lifespan of their host plants, employing multiple strategies to ensure long-term survival. This study reveals an unusual self-attenuation mechanism in which potyvirids, likely through recombination, discard a large genomic fragment containing the RNA silencing suppressor coding sequence. This deletion reduces viral pathogenicity, enabling a peaceful long-term virus-plant coexistence. Meanwhile, the attenuated viruses may function as natural vaccines, protecting plants from reinfection by the full-length pathogenic strains or related variants. These findings highlight a direct link between viral evolution and long-term coexistence, suggesting that such adaptations may promote mutual benefits. Understanding these dynamics could provide valuable insights into virus-host interactions and inspire new approaches to plant disease management.

pathology↗