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Liu, Z.

Publications and source records attributed to Liu, Z..

At least 289 records · Page 16Linked to original sources

BrainBeacon: A Cross-Species Foundation Model for Single-cell Resolved Brain Spatial Transcriptomics

The brains functional complexity emerges from spatiotemporal heterogeneity in molecular, cellular, and circuit organization, shaped by evolution, aging, and disease. Single-cell spatial transcriptomics provides a transformative framework to decode this complexity, resolving cell-type-specific expression patterns, region-specific regulation, evolutionary divergence, and disease-associated disruptions. Despite recent advances in spatial transcriptomics, a unified foundation model capturing cross-species, whole-brain cellular architecture remains lacking. Here, we introduce BrainBeacon, the first cross-species foundation model for whole-brain spatial transcriptomics. Trained on 133 million spatially resolved cells covering a total area of 210194 mm2 from human, macaque, marmoset and mouse brains profiled across five major platforms, BrainBeacon integrates gene expression rankings, spatial cellular organization, and evolutionarily conserved genetic relationships into a unified transformer-based architecture. A two-stage training strategy captures both intra-cellular transcriptional dependencies and inter-cellular spatial interactions, yielding biologically grounded and interpretable representations of brain structure. Subsequently, BrainBeacon enables cross-species alignment of brain cell types and anatomical regions, facilitating integrative analyses of conserved and divergent cellular architectures. Moreover, it uncovers spatial regulatory mechanisms of aging by predicting bidirectional perturbation responses between cells and their local niche. Together, BrainBeacon serves as a foundational cross-species model for whole-brain spatial transcriptomics, enabling virtual brain atlas construction, systematic in silico perturbation studies, and mechanistic insights into brain disease pathogenesis.

bioinformatics↗

Reproducibility of Scientific Claims in Drosophila Immunity: A Retrospective Analysis of 400 Publications

Drosophila immunity has been the focus of intense study and has impacted other research fields including innate immunity and agriculturally or epidemiologically relevant investigations of insect pests and vectors. Unsurprisingly for such a large body of work, some published results were later found to be irreplicable. Although some results have been contradicted in the literature, many have no published follow-up, either due to a lack of research or low motivation to publish negative or contradictory results. We have addressed this by performing a reproducibility project that analyses the conceptual replicability of claims from articles published on Drosophila immunity before 2011. To assess replicability, we extracted claims from 400 articles on the Drosophila immune response to bacteria and fungi and performed preliminary verification by comparing these claims to other published literature in the field. Using alternative approaches, we also experimentally tested some unchallenged claims, with no published follow-up. The intent of this analysis was to centralize evidence on insights and findings to improve clarity for scientists that may base research programs on these data. Although the aim of the ReproSci project is to assess the replicability of claims made in articles published in the field of Drosophila immunity, it is in no way an assessment of the scientific value of the research. All our data are published on a publicly available website associated with this article (https://ReproSci.epfl.ch/) that encourages community participation. This article provides a short summary of claims that were found to have contradictory evidence, which may help the community to assess past findings on Drosophila immunity and improve clarity going forward. Statistical analysis of this reproducibility study and metascience insights obtained from this approach are discussed in a companion article.

genetics↗

WaveLimit: An optimal spike sorting inclusion boundary

Spike sorting is the process of assigning neuronal action potentials to individual putative neurons based on extracellular recordings. Spike sorting may be partitioned into five major components: i) raw neural data is filtered, ii) spiking events are extracted as waveforms, iii) features are extracted from the waveforms, iv) clusters of waveforms are defined, and v) individual waveforms are assigned to their respective clusters. Here, we focus on the often underappreciated fifth component, deriving a useful principle to define a cluster boundary to maximize the theoretical information available from a single neuron. We implemented this boundary, along with an automatic cluster identifier, in a novel spike sorting algorithm, WaveLimit. We then compared WaveLimit to three state-of-the-art spike sorters. WaveLimit identified either the same or more units and included more spiking events per unit than the other sorters. WaveLimit also found units with fewer inter-spike interval violations and higher signal-to-noise ratios. Thus, better defining the cluster boundary improved spike sorting.

neuroscience↗

MetaNet: a scalable and integrated tool for reproducible omics network analysis

Network analysis is a powerful strategy for uncovering complex relationships in high-throughput omics datasets. However, current tools often lack scalability, flexibility, and native support for multi-omics integration, posing significant barriers for exploring complex biological networks. To address these limitations, we developed MetaNet, a high-performance R package designed to construct, visualize, and analyze biological networks from multi-omics datasets. MetaNet supports highly efficient correlation-based network construction, scalable to datasets with over 10,000 features, and includes extensive layout algorithms and visualization options compatible with both static and interactive platforms. It also provides a comprehensive suite of topological and stability metrics for in-depth network characterization. Benchmarking results show that MetaNet outperforms existing R packages by up to 100-fold in computation time and reduces memory usage by up to 50-fold. We demonstrate its utility through two case studies: (1) a longitudinal analysis of microbial co-occurrence networks showing the dynamics of the airborne microbiome, and (2) an integrative exposome-transcriptome network of more than 40,000 features, uncovering distinct regulatory impacts of biological and chemical exposures. MetaNet bridges the gap between network theory and omics application by offering a robust, reproducible, and biologically informed framework for large-scale, interpretable, and integrative network analyses across diverse omics platforms, advancing systems-level understanding in modern life sciences. MetaNet is available on the Comprehensive R Archive Network (https://cran.r-project.org/web/packages/MetaNet).

bioinformatics↗

Prior knowledge influences the neural mechanisms supporting memory-based inference

Memory allows us to go beyond direct experience by enabling inference across separate events. Yet how prior knowledge shapes the mechanisms supporting such inferences remains unclear. Here, we show that alignment between ongoing experience and existing knowledge determines how the brain constructs cross-event inferences. Behaviorally, inferences across schema-congruent events did not require accurate retrieval of the individual episodes, whereas inferences across schema-incongruent events depended on successful retrieval of those episodes. EEG-based multivariate pattern analysis further showed that schema-congruent inference was supported by schema reinstatement during encoding, consistent with the formation of integrated memory representations. In contrast, schema-incongruent inference relied on context-specific reinstatement at retrieval, reflecting the flexible recombination of distinct memories. Together, these findings demonstrate that prior knowledge dynamically shapes memory toward integration or separation, revealing how the brain constructs inferences to support flexible cognition.

neuroscience↗

Spatial Coordination between Leaf Gradient and Temperature Response in Barley

The linear shape of cereal leaves creates distinct longitudinal zones that coordinate tissue maturation and resource allocation. Under abiotic stress such as heat, these longitudinal zones may differentially activate protective pathways, revealing hidden heterogeneity in stress response that remains poorly understood. Barley (Hordeum vulgare), a cold-adapted crop particularly sensitive to elevated temperatures, can serve as an ideal model for studying region-specific heat responses in leaves. Using chlorophyll fluorescence imaging, we found that non-photochemical quenching (NPQ) kinetics captured additional physiological changes beyond those detected by SPAD, highlighting the added value of chlorophyll fluorescence-based assessments. NPQ kinetics traits displayed consistent spatial gradients from tip to base, with heat stress reducing NPQ induction across leaf gradients. Genome-wide association analysis of traits derived from chlorophyll fluorescence imaging across leaf gradients identified significant SNPs within multiple candidate genes, including HORVU.MOREX.r3.3HG0262630 that was consistently detected in over 90% resampling iterations under heat stress, suggesting its key role during heat responses. Transcriptomic profiling along the leaf axis revealed both conserved and region-specific heat responses between leaf regions. Conserved activations highlighted conserved heat response pathways, including the reactivation of the Arabidopsis thermomemory module FtsH6-HSP21. In contrast, the region-by-temperature interaction analysis identified 40 genes with spatial responses indicative of resource reallocation from growth to defense, including those involved in growth and transport. The integration between spatially resolved phenotyping and transcriptional profiling underscores region-specific variation in response to heat along the leaf axis, guiding targeted strategies to enhance heat resilience in barley and other cereal crops.

plant biology↗

Agropyron cristatum genome provides a new insight for wheat improvement with wild relatives

Exploring novel genetic variation for target traits is crucial for advancing wheat breeding and genetic improvement. Since 1990, we have been transferring genes from Agropyron cristatum, a promising wild relative genetic resource featuring robust spike morphology and stress tolerance, into common wheat by distant hybridization. To efficiently harness A. cristatum genes, we de novo assembled a 25.62-Gb high-quality genome of an autotetraploid accession Z559 with 28 chromosomes, and uncovered its specific genome features and an extensive repertoire of genes associated with yield and resistance to abiotic and biotic stresses. We systematically characterized A. cristatum genome introgressions by resequencing 431 wheat-A. cristatum derivatives and cloned the gene AcGNS1, which functions in the regulation of grain number per spike in wheat. Subsequently, we developed an optimized genome-selection model for wheat-A. cristatum breeding derivatives, enabling the rapid selection of new potential varieties. These findings demonstrate a genomic breeding strategy for leveraging novel genetic resources of wild relatives and advancing wheat improvement.

genomics↗

Early transcriptional signatures of MeCP2 positive and negative cells in Rett syndrome

Rett syndrome (RTT) is an X-linked neurological disorder caused by MECP2 mutations. Like other X-linked disorders, RTT patients have sex-specific differences in clinical presentation due to distinct cellular environments, where females have [~]50% of cells expressing either a mutant or wild-type copy of MECP2 (mosaic) and males have 100% of cells expressing a mutant MECP2 (non-mosaic). Typical RTT females have a short window of normal early development until [~]6-18 months, followed by regression and progressive decline, whereas neonatal encephalopathy is more likely in RTT males. How these sex-specific differences in cellular context contribute molecularly to RTT pathogenesis, particularly in the presymptomatic stages of RTT females, remains poorly understood. Here, we profiled the hippocampal transcriptomes of female (Mecp2+/-) and male (Mecp2-/y) RTT mice at early timepoints using both bulk and single-nucleus RNA-seq, including sorted MeCP2 positive (MeCP2+) and MeCP2 negative (MeCP2-) neurons in female mice. We identified a core disease signature consisting of 12 genes consistently dysregulated only in MeCP2-cells across RTT models. Moreover, we uncovered non-cell-autonomous effects exclusively in female MeCP2+ excitatory neurons, but not inhibitory neurons, suggesting excitatory circuits are more vulnerable early in the mosaic RTT environment. The single-nuclei data also revealed that a previously underappreciated MeCP2-interneuron subtype had the most transcriptional dysregulation in both male and female RTT hippocampi. Together, these data highlight the different effects of MeCP2 loss on excitatory and inhibitory circuits between the mosaic and non-mosaic environment that appear early in RTT pathogenesis.

neuroscience↗

Population-specific brain charts reveal Chinese-Western differences in neurodevelopmental trajectories

Human brain charts provide unprecedented opportunities for decoding neurodevelopmental milestones and establishing clinical benchmarks for precision brain medicine 1-7. However, current lifespan brain charts are primarily derived from European and North American cohorts, with Asian populations severely underrepresented. Here, we present the first population-specific brain charts for China, developed through the Chinese Lifespan Brain Mapping Consortium (Phase I) using neuroimaging data from 43,037 participants (aged 0-100 years) across 384 sites nationwide. We establish the lifespan normative trajectories for 296 structural brain phenotypes, encompassing global, subcortical, and cortical measures. Cross-population comparisons with Western brain charts (based on data from 56,339 participants aged 0-100 years) reveal distinct neurodevelopmental patterns in the Chinese population, including prolonged cortical and subcortical maturation, accelerated cerebellar growth, and earlier development of sensorimotor regions relative to paralimbic regions. Crucially, these Chinese-specific charts outperform Western-derived models in predicting healthy brain phenotypes and detecting pathological deviations in Chinese clinical cohorts. These findings highlight the urgent need for diverse, population-representative brain charts to advance equitable precision neuroscience and improve clinical validity across populations.

neuroscience↗

Pathogenicity and transmissibility of Monkeypox virus in dormice

The global spread of the monkeypox virus (MPXV) poses a significant challenge to public health, yet reliable and consistent animal models for evaluating MPXV remain limited, which to some extent restricts the advancement of treatment strategies and transmission-blocking technologies. As natural hosts, African dormice (Graphiurus spp.) represent promising candidates. However, the biological characteristics of MPXV in dormice remain largely unexplored. This study systematically evaluated the pathogenicity and transmissibility of MPXV in dormice. Experimental results demonstrated that dormice are highly susceptible to MPXV infection. Following intranasal inoculation, MPXV induced significant weight loss, lethal infections, and multi-organ pathological damage, with robust viral replication in respiratory and liver tissues. Notably, MPXV can efficiently transmit among dormice through direct contact, with one-third of the contact-exposed dormice shedding infectious viruses and two-thirds exhibiting seropositivity. In addition, one-third of the airborne exposure dormice show seropositivity, yet no infectious viruses were detected in their respiratory tissues, indicating that the airborne transmissibility of MPXV among dormice is relatively restricted. Furthermore, it was observed that infected dormice continuously released large quantities of virus-laden aerosols, with emissions peaking on 12 dpi (3.78{+/-}1.01x106 copies/dormouse/hour of respiration). Particle size analysis revealed that the viral copies in [≥]7 m coarse particles accounted for >90.9% of exhaled viral aerosols during peak shedding (8-14 dpi). These findings demonstrate that the African dormice serve as an effective animal model for assessing MPXV infection, pathogenicity, and transmission dynamics. Simultaneously, enhanced monitoring of wild dormouse populations is critical due to their potential role in MPXV transmission chains.

microbiology↗

A bottom-up approach to understanding ultrasound mediated blood-brain barrier opening using long and short pulses

Ultrasound-mediated blood-brain barrier (BBB) opening is promising for non-invasive, localized, and reversible drug delivery to the brain. However, the underlying mechanisms remain unclear, particularly at microscopic level in real time. Recently developed short-pulse ultrasound enhances safety by reducing side effects compared to conventional long-pulse ultrasound. Using vessel-mimicking microchannels cultured with brain endothelial monolayers, we directly observed bubble dynamics and cellular bioeffects under flow conditions. Intriguingly, cyclic jetting during stable cavitation occurs at long-pulse mode, accompanied by a few localized cell detachments and extensive sonoporation. In contrast, short-pulse ultrasound induced milder, uniform bubble dynamics, reversible sonoporation and calcium signaling, promoting safer BBB modulation. In vivo two-photon imaging and histology in mice confirmed these findings, showing that long-pulse ultrasound enabled higher drug delivery efficiency but caused localized endothelial damage, while short-pulse ultrasound facilitated uniform delivery and faster BBB recovery. The differential bubble dynamics and cellular responses correlated well between in vitro and in vivo models. This study establishes a cross-scale framework for real-time analysis of ultrasound-mediated BBB opening, revealing key biophysical factors governing safety and efficacy. The findings provide guidance for the optimization of ultrasound protocols for vascular drug delivery, with potential applications in treating brain tumors, neurodegenerative diseases, and other disorders.

biophysics↗

Dendritic cell-intrinsic TLR/MyD88 signaling promotes the clearance of a live-attenuated oral vaccine

A genital tract pathogenicity-attenuated Chlamydia muridarum mutant, named intrOv, is being developed into an oral vaccine against C. trachomatis infection in the genital tract. Although wild-type C. muridarum persists in the mouse large intestine for long periods, intrOv is cleared by the group 3 innate lymphoid cells that produce IFN{gamma} (IFN{gamma}+ILC3s). The current study aims to reveal the mechanism by which intrOv induces IFN{gamma}+ILC3s for its own clearance from the large intestine. IntrOv-induced IL-23 and IL-23 signaling were required for the clearance of intrOv from the large intestine. The intrOv clearance depended on dendritic cells, as depletion of CD11c+ cells reduced both IL-23 and IFN-{gamma}, resulting in the growth of intrOv. Deletion of MyD88 from dendritic cells, but not phagocytes or epithelial cells, rescued the growth of intrOv, indicating a critical role of MyD88 signaling in dendritic cells. Furthermore, TLR2/4 signaling is also essential for inhibiting intrOv, as the deficiency in TLR2/4 fully rescues the growth of intrOv. Both the TLR and MyD88 signaling must be in the same dendritic cells to inhibit intrOv, as the growth of intrOv in the MyD88- or TLR2/4-deficient mice was blocked by only wild-type bone marrow-derived dendritic cells but not dendritic cells deficient in either MyD88 or TLR2/4. Thus, we have demonstrated a dendritic cell-intrinsic TLR/MyD88/IL-23 pathway for recruiting effectors to clear intrOv from the large intestine. The information may help further improve the efficacy and safety of intrOv and guide the design of future mucosal vaccines.

immunology↗

Functional loss of CHS2 confers high levels resistance to Bacillus thuringiensis Vip3Aa, but with significant fitness costs in five lepidopteran species

Bacillus thuringiensis (Bt) crops, engineered to produce insecticidal proteins such as Vip3Aa and Cry toxins, have revolutionized pest management by providing a sustainable alternative to chemical pesticides. However, the development of resistance to these toxins has driven the investigation of underlying mechanisms to better understand how pests evade toxicity and to develop more effective resistance management strategies. Recently, a laboratory-selected Spodoptera frugiperda strain exhibited a high level of resistance to Vip3Aa (resistance ratio: 5562-fold), with the mutation of the chitin synthase gene, SfCHS2, identified as a key factor. In this study, we extend these findings to additional lepidopteran species, including Spodoptera exigua and Agrotis ipsilon. Our results show that CHS2 knockout strains lack the peritrophic matrix (PM), while the resistant Sfru_R3 strain retains its PM. Knockout of this gene resulted in high levels resistance to Vip3Aa. These findings further validate the role of the CHS2 gene in Vip3Aa resistance and highlight its potential as a target for resistance management in lepidopteran pests. This study advances our understanding of the molecular mechanisms behind resistance to Vip3Aa and supports the development of strategies to delay resistance in Bt crop management.

genetics↗

Positional frequency chaos game representation for machine learning-based classification of crop lncRNAs

Alignment-based methods are fundamental for sequence comparison but are often computationally prohibitive for large-scale genomic analyses. This limitation has spurred the development of quicker, alignment-free alternatives, such as k-mer analysis, which are crucial for studying long noncoding ribonucleic acids (lncRNAs) in plants. These lncRNAs play critical roles in regulating gene expression at both the epigenetic and transcriptomic levels. However, existing alignmentfree approaches typically lose positional information, which can be vital for achieving accurate classification. We propose positional frequency chaos game representation (PFCGR), a novel encoding that improves the traditional frequency chaos game representation (FCGR) by incorporating four statistical moments of k-mer positions: mean, standard deviation, skewness, and kurtosis. This creates a multi-channel image representation of genomic sequences, enabling machine learning models such as Logistic Regression, Random Forests, and Convolutional Neural Networks to classify plant lncRNAs directly from raw genomic sequences. Tested on seven major crop species, our PFCGR-based classifiers achieve classification accuracies comparable to or exceeding those of the computationally intensive DNABERT-based model [1], while requiring 80% to 95% less computational time. These results demonstrate PFCGRs potential as an efficient and accurate tool for plant lncRNA identification, as well as its ability to facilitate large-scale computational studies in genomics.

bioinformatics↗

Dynamic Magnetic Resonance Imaging of Whole-Stomach Motility in Rats

ObjectiveUnderstanding gastric physiology in rodents is critical for advancing preclinical neurogastroenterology research. However, existing techniques are often invasive, terminal, or limited in resolution. This study aims to develop a non-invasive, standardized MRI protocol capable of capturing whole-stomach dynamics in anesthetized rats with high spatiotemporal resolution. MethodsExperiments were performed in a 7-Tesla MRI system. Gadolinium-doped test meals were prepared to enhance intraluminal contrast in T1-weighted MRI. Based on a modified multi-slice gradient-echo sequence, our protocol integrates respiratory gating to minimize motion artifacts, spatial saturation to improve intraluminal contrast, and slice grouping to optimize the trade-offs between signal-to-noise ratio and motion sensitivity. Image acquisition was accelerated using a time-interleaved k-space undersampling scheme, with missing data reconstructed through k-t interpolation. Image quality and gastric motility were quantitatively assessed. ResultsThe protocol enabled successful imaging of the stomach and visualization of its pseudo-periodic dynamics in anesthetized rats. The gadolinium-doped meal produced relatively homogeneous intraluminal contrast, allowing clear delineation of gastric anatomy, volume, and motility. The retrospectively reconstructed image exhibited high image quality and yielded reliable estimates of antral contractions, confirming the effectiveness and robustness of k-t interpolation method. Estimated antral contraction amplitude and velocity showed minimal deviations from the reference values, whereas contraction frequency estimation remained highly consistent and accurate. Prospective acquisitions using the accelerated imaging protocol successfully imaged the entire stomach and major intestinal regions, acquiring 24 slices every < 3 s and capturing antral contraction at [~]5 cycles per minute. ConclusionWe established an accessible and standardized imaging protocol that encompasses contrast meal preparation, animal handling and training, and a contrast-enhanced dynamic GI MRI acquisition and reconstruction framework. SignificanceThis protocol provides a comprehensive, robust, non-invasive tool for studying gastric motility and dysmotility in rodents, offering strong potential to advance preclinical gastrointestinal motility research. Graphic AbstractIn this paper, we report a standardized, non-invasive imaging protocol that encompasses animal handling and training, contrast meal preparation, and a contrast-enhanced dynamic GI MRI acquisition and reconstruction framework for imaging whole-stomach dynamics in anesthetized rats. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=39 SRC="FIGDIR/small/657757v1_ufig1.gif" ALT="Figure 1"> View larger version (13K): org.highwire.dtl.DTLVardef@1b0aa4org.highwire.dtl.DTLVardef@157a67aorg.highwire.dtl.DTLVardef@172a2a2org.highwire.dtl.DTLVardef@1136db6_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Two routes from the Fertile Crescent led to the introduction of common vetch into Europe.

Vicia sativa (common vetch, n=6) is an annual leguminous plant with high drought tolerance and high grain protein content. Historically and still today, vetches are important for nitrogen fixation to maintain cereal yields and feeding grazing livestock. In this study, we re-sequenced the genomes of 279 common vetch accessions from a wide geographic range covering western Eurasia and North Africa to construct a comprehensive nucleotide variation map. Population structure analyses indicate that the Middle Eastern region was the centre of origin of common vetch, which then entered Europe in two distinct waves. One wave propagated by humans through Turkey into the Carpathian Basin before spreading throughout Europe via "Danubian" and "Mediterranean" routes. Demographic inferences revealed a significant bottleneck for all common vetch groups initiated during the Last Glacial Maximum, followed by an expansion that coincides with the onset of the warm Holocene epoch and the Neolithic Revolution. Interestingly, we identified selective sweeps for the flowering time regulators VsSOC1 and VsFTb2 in northern latitude populations suggesting that both genes are important regulators of latitudinal adaptation. Overall, we provide valuable genomic resources for conservation and breeding programs to optimize food production in the face of population growth and reduced agricultural resources.

plant biology↗

Profiling Cytosolic Drug Delivery in Mammalian Cells: A Generalizable Assay for Intracellular Accumulation

The ability of biologically active molecules to access intracellular targets remains a critical barrier in drug development. While assays for measuring cellular uptake exist, they often fail to distinguish between membrane-associated or endosomal trapped compounds and those that successfully reach the cytosol. Here, we present the Chloroalkane HaloTag Azide-based Membrane Penetration (CHAMP) Assay, a novel high-throughput method that employs a minimally disruptive azide tag to report the cytosolic accumulation of diverse molecules in mammalian cells. The CHAMP assay utilizes HaloTag-expressing cells and strain-promoted azide-alkyne cycloaddition (SPAAC) chemistry to quantify the presence of azide-tagged test compounds in the cytosol. We demonstrate the versatility of this approach by evaluating the accumulation profiles of small molecules, peptides, and proteins, revealing how structural variations and stereochemical differences influence cytosolic penetration. Our findings with cell-penetrating peptides confirm established structure-activity relationships, with longer polyarginine sequences showing enhanced accumulation. Additionally, we observed that C-terminal amidation and D-amino acid substitutions significantly impact cellular penetration. When applied to supercharged proteins and antibiotics, CHAMP successfully discriminates between compounds with varying accumulation capabilities. This method provides a robust platform for screening cytosolic accumulation while minimizing the confounding effects of large tags on molecular permeability, potentially accelerating the development of therapeutics targeting intracellular pathways.

biochemistry↗

Improved genome assembly of double haploid Prunus persica siblings Lovell 2D and Lovell 5D and the peach NLRome

Prunus persica (peach) has long served as a model fruit tree for studying phenological events. It has a relatively small genome and exhibits tremendous plasticity in climate tolerances due to the high variation of chill requirements, bloom times, and fruit ripening times. The peach variety Lovell 2D was used to generate one of the first high-quality genome assemblies for a tree species, using Sanger sequencing of genetic-map ordered BAC clones. A key to the high quality of this early assembly was the use of a doubled haploid variety, which eliminates the challenges posed by mixed haplotypes. Here, we re-sequenced and assembled the Lovell 2D genome along with a doubled haploid sibling Lovell 5D using 3rd generation technologies. The resulting genomes were significantly more contiguous than the current Lovell 2D reference genome (ver2.0 updated in 2017) and are closer to the estimated total genome size for peach (265Mb). In addition, new gene, transposable element (TE), and Nucleotide-binding domain and Leucine-rich repeat receptor (NLR) annotations were performed to enhance the integrity and utility of the genome. These updated peach doubled-haploid reference assemblies will provide the research community with an improved reference genome for genomics-guided studies and breeding efforts.

genomics↗