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Biology subjects

Sato, Y.

Publications and source records attributed to Sato, Y..

At least 37 records · Page 2Linked to original sources

Macrophage extracellular traps promote maladaptive cardiac remodelling and heart failure via PAD4-dependent mechanisms

AimsThe activation of inflammatory cells, particularly macrophages, plays a pivotal role in the pathogenesis of cardiac remodelling and heart failure. Emerging evidence indicates that extracellular traps released from inflammatory immune cells contribute to the progression of various pathologies. However, the clinical relevance and mechanistic role of macrophage extracellular traps (METs) in heart failure remain to be elucidated. Methods and ResultsEndomyocardial biopsy specimens from 69 patients with heart failure were analysed by fluorescent immunostaining to identify and quantify METs. The numbers of METs per myocardial tissue area in patients with heart failure showed a negative correlation with left ventricular (LV) ejection fraction and a positive correlation with LV end-diastolic diameter. Patients with higher MET counts had significantly lower event-free survival from the composite cardiac events. In a murine model of pressure overload by transverse aortic constriction (TAC), METs were most abundantly observed at 3 days post-TAC and remained detectable throughout the 4-week observation period. In vitro, time-dependent MET formation was induced by an intrinsic trigger of mitochondrial DNA in bone marrow-derived macrophages from wild-type (WT) mice, but not in peptidyl arginine deiminase 4 (PAD4)-deficient macrophages, indicating that PAD4 activity is indispensable for MET formation. The recipient mice transplanted with bone marrow cells from PAD4 knockout mice showed more preserved cardiac function, reduced myocardial fibrosis, and improved survival in response to TAC, compared to those transplanted with WT mice. Ex vivo analyses demonstrated that conditioned medium containing METs from WT macrophages induced fibroblast-to-myofibroblast transition via Toll-like receptor 4 signalling. ConclusionsPAD4-dependent MET formation from bone marrow-derived macrophages represents a novel driver of cardiac remodelling. Targeting MET formation may offer a potential therapeutic strategy for heart failure. Translational PerspectiveMacrophage extracellular traps (METs) are abundant in myocardial tissue from patients with heart failure with reduced ejection fraction and are associated with adverse left ventricular remodelling and worse clinical outcomes. These findings support myocardial MET burden as a potential tissue biomarker to improve risk stratification in heart failure patients. In mice, pressure overload induces MET formation, and hematopoietic PAD4 deficiency suppresses myocardial METs, attenuates fibrosis, preserves cardiac function, and improves survival. Mechanistically, mitochondrial DNA-enriched cardiomyocyte-derived exophers trigger PAD4-dependent METs, which activate cardiac fibroblasts through TLR4 signalling. Suppressing METs represents a potential therapeutic strategy to attenuate the progression of heart failure. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/711858v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@11b9b57org.highwire.dtl.DTLVardef@17386f7org.highwire.dtl.DTLVardef@1a1f002org.highwire.dtl.DTLVardef@942bbc_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

UFD1 Recognition of Initiator and Proximal Ubiquitin Drives p97-Mediated Substrate Unfolding enhanced by FAF1, FAF2, and UBXD7

The AAA-ATPase p97 and its primary adaptor UFD1-NPL4 (UN) unfold ubiquitinated substrates for their proteasomal degradation. Although cryo-EM has shown that substrate processing begins with unfolding of the initiator ubiquitin and its capture by NPL4, the specific contribution of UFD1 to K48-linked ubiquitin chain engagement has not been fully defined. Here we report a 1.31 [A] crystal structure of the human UFD1-UT3 bound to a K48-linked di-ubiquitin mimic, revealing that UFD1-UT3 engages the unfolded initiator ubiquitin via its Nc subdomain and the proximal ubiquitin via its Nn subdomain. AlphaFold3-guided analyses further demonstrate that accessory adaptors FAF1, FAF2, and UBXD7 enhance p97-UN activity through divergent strategies. FAF1 and FAF2 scaffold UFD1-UT3 near the NPL4-tower, whereas UBXD7 stabilizes transient interactions between UFD1 and the ubiquitin chain. Our results provide a comprehensive molecular model for the initiation of p97-mediated substrate unfolding.

biochemistry↗

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↗

Three-dimensional redistribution of pelagic fish aggregations associated with floating offshore wind farms

Floating offshore wind farms (F-OWFs) are rapidly expanding into offshore pelagic environments, yet their ecological consequences remain poorly resolved because quantitative, non-invasive monitoring is challenging at sea. Here, we integrated environmental DNA (eDNA) metabarcoding and scientific echosounding to assess fish community composition and three-dimensional aggregation structure around a commercial-scale F-OWF off the Goto Islands, Japan. We compared four stations adjacent to turbines with four offshore control stations under comparable environmental conditions across five sampling periods (April and August 2024; May, June, and August 2025) and three depth layers (5, 50, and 80-160 m). eDNA metabarcoding detected 126 fish species, and community structure based on the 30 most frequently detected taxa did not differ significantly between the F-OWF and control areas (Bray-Curtis PERMANOVA, p = 0.60). Species richness varied strongly with sampling period and water layer, with a significant water layer x period interaction, whereas overall richness did not differ between areas (Mann-Whitney U test, p = 0.18). In contrast, acoustic surveys revealed a marked difference in vertical structuring of fish aggregations: in the control area, NASC per mile increased with depth, while this depth-dependence disappeared near turbines. Moreover, the weighted mean normalized depth (WMND) indicated a shallower vertical center of aggregation in the F-OWF area (0.34) than in the control area (0.24), consistent with turbine-associated redistribution in the water column. Although voyage-level integrated NASC per mile did not differ significantly between areas (t-test, p = 0.83), mean values were higher near turbines. Together, these results indicate that F-OWFs can be associated with changes in the three-dimensional organization of fish aggregations without producing pronounced shifts in dominant taxonomic composition. Our study demonstrates the value of combining eDNA metabarcoding and acoustics for evaluating ecological effects of offshore renewable-energy infrastructures and provides a framework for standardized, long-term monitoring as F-OWF deployment accelerates globally.

ecology↗

Extrinsic MMPs drive epithelial shape change via basal ECM disassembly in the Drosophila wing disc

Epithelial morphogenesis generates complex tissue architectures with remarkable reproducibility, yet how such self-organized shape transformations are triggered in vivo remains poorly understood. Here, we show that epithelial morphogenesis during early pupal development of the Drosophila wing disc is regulated non-autonomously through remodeling of the basal extracellular matrix (ECM) by neighboring tissues. Live imaging analyses reveal a previously unrecognized epithelial shape transition at the larval-to-pupal stage, in which the wing disc epithelium transforms from a concave to a convex configuration. Rather than being driven autonomously by the epithelium, this morphogenetic transition depends on adjacent non-epithelial cell populations, including myoblasts and tracheal cells. Mechanistically, systemic ecdysone signaling activates Mmp1 and Mmp2 in these neighboring tissues, leading to spatially restricted basal ECM disassembly that permits collective epithelial shape reorganization. Together, our findings establish ECM remodeling at tissue interfaces as a non-autonomous regulatory layer that enables epithelial self-organization during development.

developmental biology↗

Heterogeneous Nuclear Ribonucleoprotein A1 as a Key Regulator in Pulmonary Arterial Hypertension Development

BackgroundAlthough plexiform lesion (PL) formation in severe pulmonary arterial hypertension (PAH) is a therapeutic target, the mechanisms underlying their formation have not been fully elucidated. This study aimed to identify candidate proteins involved in PL formation by examining differentially expressed proteins (DEPs) in PAH lesions. MethodsProteomic remodeling was assessed before and after the formation of PLs in a SU5416 combined with hypoxia (SuHx) rat model of severe PAH using laser-capture microdissection coupled with mass spectrometry. Unobstructed pulmonary arteries with medial hypertrophy (UMHPAs) and PLs from SuHx rats were subjected to qualitative and quantitative proteomics, revealing DEPs between these structures. ResultsWe identified 718 proteins with 58 DEPs, of which 31 were upregulated in UMHPAs and 27 were upregulated in PLs. Immunostaining confirmed that DEPs detected in our proteomic analysis were differentially expressed between UMHPAs and PLs. Among them, we focused on heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) as a candidate protein that may be strongly associated with PL formation because of its strong association with cell proliferation. siRNA knockdown of hnRNPA1 in hypoxia-treated pulmonary artery smooth muscle cells reduced pyruvate kinase M2 expression and significantly decreased proliferative capacity. Treatment of SuHx rats with hnRNPA1 inhibitors also suppressed pulmonary artery remodeling in PAH and PL formation. ConclusionsSeveral DEPs associated with PL formation but with unclear relevance to pulmonary artery remodeling in PAH were discovered. Among these, hnRNPA1, which was not detected in transcriptome analysis, may be important in PL formation. What are the Clinical Implications?The prognosis for pulmonary arterial hypertension (PAH) with plexiform lesions (PLs) is poor. Although PLs are therapeutic targets, the mechanisms of PL formation have not been fully elucidated, and there have been no direct examinations of proteomic remodeling before and after their formation. We identified several differentially expressed proteins (DEPs) that may be strongly associated with PL formation. Of these, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was examined as a candidate protein involved in PA remodeling in PAH and PLs. Inhibition of hnRNPA1 in a severe PAH model not only suppressed pulmonary artery remodeling in PAH but also reduced PL formation. Several DEPs involved in pulmonary artery remodeling in PAH may be of significant value in the search for new therapeutic targets.

cell biology↗

Design-of-Experiments for Nonlinear, Multivariate Biology: Rethinking Experimental Design through Perturb-seq

Design of experiments (DOE) principles are increasingly applied to biological assays, yet it remains unclear whether the optimality of their foundational assumption--orthogonal decomposition--holds in nonlinear biological systems. We addressed this question using Perturb-seq as a case study. By benchmarking a design commonly used in Perturb-seq and related experiments against the orthogonal Plackett-Burman (PB) design via simulations, we uncovered a counter-intuitive phenomenon: while orthogonal designs generally excel, the correlated structure inherent to the common design is functionally robust in systems with significant signal amplification. This challenges the blind application of DOE to biology. Based on these findings, we developed the PB suitability index (PBSI), a simple, parameter-free metric that predicts the optimal design solely from network structure. Our work not only provides practical guidelines for Perturb-seq but also establishes a "biology-oriented DOE" framework, bridging the gap between statistical rigor and biological complexity.

bioinformatics↗

Dissecting Epstein-Barr Virus Dependence Across Diverse Infected Cell Models

Epstein-Barr virus (EBV) is maintained clonally in a wide array of tumors and cells of lymphoproliferative disorders, yet the degree to which these infected cells continuously depend on EBV remains unresolved. To directly assess EBV dependence, we used two complementary Cas9-based viral eviction strategies: 1) targeting EBNA1 to promote episome dilution during cell division, and 2) targeting repetitive viral genomic regions to rapidly degrade EBV episomes. Using these approaches, we evaluated EBV-loss sensitivity across newly-derived, phenotypically diverse EBV-positive Burkitt lymphoma lines. We also evaluated cell lines from patients with EBV-associated T/NK and epithelial malignancies. We included the Burkitt Lymphoma cell line, Akata-GFP, as our EBV-loss-tolerant control and a lymphoblastoid cell line as our EBV-loss-sensitive control. We observed EBV-loss sensitivity in all the EBV-positive Burkitt Lymphoma cell lines and the chronic active EBV disease cell line. In contrast, the EBV-positive gastric adenocarcinoma lines were markedly less sensitive to EBV loss. EBV latency type did not predict EBV dependence, indicating that viral gene expression programs alone do not dictate reliance on the virus. These findings demonstrate that EBV dependence is prevalent across multiple EBV-associated disease models and is especially pronounced in early-state or newly derived lymphoid malignancies. AUTHOR SUMMARYEpstein-Barr virus (EBV) infects most people worldwide and is linked to many malignancies. Although EBV is present in cancer cells, it is unclear whether these cells require the virus to survive. To answer this question, we used CRISPR/Cas9-based methods to remove EBV from infected cells. Using these tools, we studied many different EBV-positive cell lines, including new Burkitt lymphoma cell lines. We found that most EBV-positive lymphoid cells required EBV for growth. In contrast, EBV-positive gastric cells were more tolerant of viral loss. These results show that many EBV-associated malignancies, especially early or newly established diseases, rely on EBV to survive.

microbiology↗

LRBA promotes drug-induced liver injury and MASLD by scaffolding MAPK activation

LPS-responsive beige-like anchor protein (LRBA) regulates vesicular trafficking and receptor recycling, and its deficiency results in immunodeficiency characterized by hypogammaglobulinemia and autoimmune syndrome. However, its role in liver pathophysiology remains unclear. Here, we reveal a previously unrecognized function of LRBA as a critical intracellular scaffold for mitogen-activated protein kinase (MAPK) activation that promotes liver injury. Lrba-/-mice exhibit reduced acetaminophen (APAP)-induced hepatic necrosis through the suppression of JNK activation. In a model of metabolic dysfunction-associated steatotic liver disease (MASLD) induced by a high-fat, high-cholesterol (HFHC) diet, Lrba deficiency reduces hepatic inflammation, fibrosis, and Kupffer cell activation. Mechanistically, LRBA homodimers directly interact with specific mitogen-activated protein kinase kinase kinases (MAP3Ks), including transforming growth factor-{beta}-activated kinase 1 (TAK1) and mixed-lineage kinase 3 (MLK3), to facilitate their activation. LRBA, which is primarily expressed in hepatocytes under physiological conditions, is upregulated in non-parenchymal cells such as Kupffer cells and cholangiocytes in both HFHC diet-fed mice and patients with MASLD and cirrhosis, linking its scaffolding function to pathological inflammation. Thus, LRBA promotes liver disease progression by amplifying inflammatory signaling.

cell biology↗

MitoNGS: an online platform to analyze fish metabarcoding data in high-resolution

Environmental DNA (eDNA) metabarcoding has become a powerful tool for assessing fish biodiversity in aquatic ecosystems. However, accurate species-level identification remains challenging due to incomplete and contaminated reference databases, as well as ambiguous taxa sharing identical barcode sequences. Here, we present MitoNGS, a next-generation platform that succeeds the widely used MiFish pipeline, designed for high-resolution analysis of fish metabarcoding data. MitoNGS addresses these challenges by incorporating more comprehensive references including non-fish species and detailed annotations of heterospecific regions. Additionally, it introduces the "species group" strategy in conjunction with environmental habitat and geographic occurrence data to resolve ambiguous taxa. Furthermore, MitoNGS expands the functionalities of the legacy MiFish pipeline. It can analyze data from any mitochondrial markers and from Nanopore sequencing platforms. MitoNGS demonstrated excellent performance on our testing datasets from diverse locations, markers and sequencing platforms. MitoNGS offers a user-friendly, web-based solution for fish detection, biodiversity monitoring, conservation research, and bioresource management. MitoNGS is freely available via https://mitofish.aori.u-tokyo.ac.jp/mito-ngs.

bioinformatics↗

Multigenerational Tracking of Reef-Building Corals Using CRISPR-Cas9induced Genetic Barcodes and eDNA Metabarcoding

Widespread biodiversity loss driven by human activity has intensified global efforts to restore degraded ecosystems. Yet a key challenge remains: how to track restored individuals and their offspring over time and space to assess the true impact of restoration? This is especially pressing for coral reefs, which support a quarter of all marine species, are in severe decline globally, and are now the focus of growing restoration initiatives worldwide. Here, we demonstrate a novel approach that combines genome editing and environmental DNA (eDNA) monitoring to enable scalable, non-invasive tracking of individual corals and their offspring. Using CRISPR-Cas9, we introduced unique genetic barcodes into non-coding regions of the Acropora millepora genome. These barcodes - stable, heritable, and distributed across the genome - will allow for individual-level identification over multiple generations. We show that these barcodes can be reliably detected in surrounding seawater using eDNA metabarcoding, offering a powerful, non-destructive tool for tracking corals in situ. Together, this approach provides a proof-of-concept for precision monitoring of restoration outcomes, with broad applicability across species and ecosystems.

genetics↗

Chromosome-scale genomes of two wild flowering cherrys (Cerasus itosakura and C. jamasakura) provide insights into structural evolution in Prunus

Flowering cherries (genus Cerasus) are iconic trees in Japan, celebrated for their cultural and ecological significance. Despite their prominence, high-quality genomic resources for wild Cerasus species have been limited. Here, we report chromosome-level genome assemblies of two representative Japanese cherries: Cerasus itosakura, a progenitor of the widely cultivated C. xyedoensis Somei-yoshino, and Cerasus jamasakura, a traditional popular wild species endemic to Japan. Using deep PacBio long-read and Illumina short-read sequencing, combined with reference-guided scaffolding based on near-complete C. speciosa genome, we generated assemblies of 259.1 Mbp (C. itosakura) and 312.6 Mbp (C. jamasakura), with both >98% BUSCO completeness. Consistent with their natural histories, C. itosakura showed low heterozygosity, while C. jamasakura displayed high genomic diversity. Comparative genomic analyses revealed structural variations, including large chromosomal inversions. Notably, the availability of both the previously published C. speciosa genome and our new C. itosakura genome enabled the reconstruction of proxy haplotypes for both parental lineages of Somei-yoshino. Comparison with the phased genome of Somei-yoshino revealed genomic discrepancies, suggesting that the cultivar may have arisen from genetically distinct or admixed individuals, and may also reflect intraspecific diversity. Our results offer genomic foundations for evolutionary and breeding studies in Cerasus and Prunus.

genomics↗

Online supervised learning of temporal patterns in biological neural networks under feedback control

In vitro biological neural networks (BNNs) provide a well-defined model system to constructively investigate how living cells interact with their environment to shape high-dimensional dynamics that could be used to generate a coherent temporal output, such as those required for motor control. Here, we developed a real-time closed-loop BNN system capable of generating periodic and chaotic temporal signals by integrating cultured cortical neurons with microfluidic devices and high-density microelectrode arrays. We show that training a simple linear decoder with fixed feedback weights enables the system to learn and autonomously generate diverse temporal patterns. When feedback was switched on, irregular activity in BNNs is transformed into low-dimensional, structured dynamics, producing coherent trajectories characterized by stable transitions between neural states. BNNs trained on different target frequencies--ranging from 4 to 30 s--could be trained to sustain oscillations at distinct frequencies, demonstrating their adaptability. Importantly, a top-down control of self-organized network formation with microfluidic devices is the key to suppress excessive synchronization and increase dynamical complexity in BNNs, facilitating the training and robust output generation. This work offers a biologically inspired platform for understanding the physical basis of cortical computation and for advancing energy-efficient neuromorphic computation. Significance StatementReservoir computing is a machine learning paradigm that exploits the transient dynamics of high-dimensional nonlinear systems. Although it was originally inspired by the mammalian brain and widely explored in physical systems, its implementations in biological neural networks (BNNs) have been limited due to their excessive connectivity and global synchrony in vitro. Here, we use microfluidic devices to construct modular, nonrandomly connected BNNs and integrate them with microelectrode arrays in a closed-loop reservoir computing environment. We show that the system can be trained to autonomously output various temporal signals, with the modular connectivity that is essential for learning. In vitro BNNs provide unique alternatives for physical reservoirs with dynamic adaptability.

neuroscience↗

The glomerulus as a selective gate for tumor-derived extracellular vesicles in urine

Urinary small extracellular vesicles (sEVs), which can reflect systemic conditions, hold great promise for non-invasive cancer diagnostics, yet the mechanism by which tumor-derived sEVs reach urine remains unclear. Here, we demonstrate that the glomerulus actively transcytoses circulating tumor-derived sEVs into urine. Using CRISPR gRNA-tagged glioma sEVs and bioluminescent/fluorescent GeNL-tagged lung and pancreatic cancer sEVs, we tracked their journey from tumors to urine in multiple mouse models. In vivo and in vitro analyses revealed endocytic uptake and transcytotic release by glomerular cells, accompanied by changes in sEV size and surface composition. GeNL-tagged sEVs consistently showed higher signals in urine than plasma, indicating selective excretion. These findings redefine the glomerulus as a dynamic regulator of EV processing and establish a mechanistic foundation for urinary liquid biopsy.

cancer biology↗

A simple and versatile plasma membrane staining method for visualizing living cell morphology in reproductive tissues across diverse plant species

Plant reproduction involves dynamic spatiotemporal changes that occur deep within maternal tissues. In ovules of Arabidopsis thaliana (A. thaliana), one of the two synergid cells degenerates at fertilization, while the fertilized egg cell (zygote) undergoes directional elongation followed by asymmetric division to initiate embryonic patterning. However, morphological analysis of these events has been hampered by the limitations of conventional cell wall staining, which fails to label cells lacking complete walls, and by the requirement for transgenic fluorescent reporters to visualize cell outlines. Here, we report that the membrane-specific fluorescent dye FM4-64 readily permeates ovules, allowing clear visualization of reproductive cell morphology both before and after fertilization. This staining method supports high-resolution time-lapse imaging and quantitative analysis of early embryogenesis in living tissues. Importantly, it is applicable not only to the angiosperm A. thaliana but also to the liverwort Marchantia polymorpha (M. polymorpha) and the fern Ceratopteris richardii (C. richardii), enabling the visualization of live reproductive cell structures within maternal tissues and revealing fertilization-associated morphological changes. This simple and robust method thus provides a valuable tool for spatiotemporal and quantitative analyses of reproductive processes across a broad range of plant species, without the need to generate transgenic lines.

plant biology↗

Integrin-binding matricellular protein fibulin-5 maintains epidermal stem cell heterogeneity during skin aging

The extracellular matrix (ECM) is crucial in building the extracellular environment and translating extracellular information into biochemical signals that sustain organ functions. Fibulin-5 (Fbln5) is a multifunctional ECM protein essential for forming elastic fibers and regulating cellular functions by binding to integrins. While fibulin-5 expression decreases with age in human skin, the functional implications of this decrease, particularly in epidermal stem cell regulation, have remained largely unexplored. Here, we find that the knocking out of Fbln5 in mice results in early impairments of epidermal stem cell properties, similar to the chronological aging of the skin. The Fbln5 deficiency suppresses the expression of integrins and other cell junction proteins, leading to the inactivation of YAP signaling in epidermal stem cells. This reduction in YAP signaling results in the downregulation of the fast-cycling epidermal stem cell marker SLC1A3 in human skin and primary keratinocytes. These results suggest that, in addition to its known function in elastic fiber formation, fibulin-5 also plays a critical role in regulating the balance of epidermal stem cell populations during skin aging and coordinating the crosstalk between the extracellular environment and intracellular signaling.

developmental biology↗

eIF4G2-Mediated Translation Initiation of Histone Modifiers Is Essential for Intestinal Stem Cell Maintenance and Differentiation

eIF4G2 (also known as NAT1, p97, or DAP5) is an evolutionally conserved protein homologous to the C-terminal two-thirds portion of eukaryotic translation initiation factor (eIF) 4G. Despite its abundant and ubiquitous expression, the physiological and pathological functions of eIF4G2 are poorly understood. Here, we show that acute loss of eIF4G2 in adult mice results in rapid weight loss with abnormalities in multiple organs, including impaired maintenance and differentiation of intestinal stem cells. Genome-wide ribosome profiling revealed that eIF4G2 is critical for the translation of key histone modification proteins involved in intestinal stemness. Our study underscores the importance of eIF4G2-mediated translation initiation in multicellular organisms.

cell biology↗

Negative frequency-dependent selection underlies overyielding through neighbor genotypic effects in Arabidopsis thaliana

Negative frequency-dependent selection (FDS) can increase both genetic diversity and population-level mean fitness. While the dual consequence of negative FDS has long been theoretically recognized, its genomic basis remains unknown. To explore a genetic link between negative FDS and overyielding, I conducted a genome-wide association study (GWAS) of neighbor genotypic effects on the growth of 98 Arabidopsis thaliana genotypes. By incorporating neighbor genotypic similarity, my GWAS detected the most significant SNP on the fifth chromosome of A. thaliana, which was 6-kbp near a known locus responsible for indirect genetic effects. I found symmetric negative FDS on the most significant SNP, such that individual plants increased their biomass in the presence of neighbors with dissimilar alleles. I also observed overyielding in which a biallelic mixture of the most significant SNP showed a 3% increase in biomass compared to monoallelic conditions. Furthermore, I focused on the genomic region near the most significant SNP and found a signature of balancing selection near a negative regulator of ethylene responses SIRTUIN2. The present analysis uncovered a key locus linking balanced polymorphisms and overyielding in A. thaliana, showing a way to understand the maintenance of polymorphism and its positive impact on population productivity.

evolutionary biology↗