The Sequence Alignment/Map format and SAMtools

Genome sequence of the wild species, Spinacia tetrandra, including a phased sequence of the extensive sex-linked region, revealing partial degeneration in evolutionary strata with unusual properties

Genetic degeneration is a striking feature of Y chromosomes, often involving losses of many genes carried on the X chromosome. However, the time course of gene losses remains unclear. Sex chromosomes of plants evolved more recently than animals' highly degenerated ones, making them ideal for studying degeneration timing. To investigate Spinacia sex chromosome evolution and the time course of degeneration, we compared genome sequences of cultivated Spinacia oleracea, with a small Y-linked region on Chr4, with its two wild relatives. In spinach and its closest relative Spinacia turkestanica, the Y duplication region (YDR) introduced a male-determining factor into Chr4's low-recombining pericentromeric region. In other words, a turnover event occurred in these species' recent common ancestor. The homologous Chr4 of the more distantly related S. tetrandra has a c. 133 Mb completely sex-linked and partially degenerated region, possibly reflecting the ancestral state. Sequence divergence analysis suggests that two 'evolutionary strata' evolved shortly before the two Spinacia lineages split. Consistent with the turnover hypothesis, the YDR of the other two Spinacia species is not within the S. tetrandra older stratum. We discuss the unexpected findings in S. tetrandra that genetic degeneration, genomic rearrangements, and repetitive sequence density are all greatest in the younger stratum.

Strategies for neoantigen screening and immunogenicity validation in cancer immunotherapy (Review)

Cancer immunotherapy stimulates and enhances antitumor immune responses to eliminate cancer cells. Neoantigens, which originate from specific mutations within tumor cells, are key targets in cancer immunotherapy. Neoantigens manifest as abnormal peptide fragments or protein segments that are uniquely expressed in tumor cells, making them highly immunogenic. As a result, they activate the immune system, particularly T cell‑mediated immune responses, effectively identifying and eliminating tumor cells. Certain tumor‑associated antigens that are abnormally expressed in normal host proteins in cancer cells are promising targets for immunotherapy. Neoantigens derived from mutated proteins in cancer cells offer true cancer specificity and are often highly immunogenic. Furthermore, most neoantigens are unique to each patient, highlighting the need for personalized treatment strategies. The precise identification and screening of neoantigens are key for improving treatment efficacy and developing individualized therapeutic plans. The neoantigen prediction process involves somatic mutation identification, human leukocyte antigen (HLA) typing, peptide processing and peptide‑HLA binding prediction. The present review summarizes the major current methods used for neoantigen screening, available computational tools and the advantages and limitations of various techniques. Additionally, the present review aimed to summarize experimental strategies for validating the immunogenicity of the predicted neoantigens, which will determine whether these neoantigens can effectively trigger immune responses, as well as challenges encountered during neoantigen screening, providing relevant recommendations for the optimization of neoantigen‑based immunotherapy.

Inhibition of acyl-CoA synthetase long-chain isozymes decreases multiple myeloma cell proliferation and causes mitochondrial dysfunction

Multiple myeloma (MM) is an incurable cancer of plasma cells with a 5-year survival rate of 59%. Dysregulation of fatty acid (FA) metabolism is associated with MM development and progression; however, the underlying mechanisms remain unclear. Herein, we explore the roles of long-chain fatty acid coenzyme A ligase (ACSL) family members in MM. ACSLs convert free long-chain fatty acids into fatty acyl-CoA esters and play key roles in catabolic and anabolic fatty acid metabolism. Analysis of the Multiple Myeloma Research Foundation (MMRF) CoMMpassSM study showed that high ACSL1 and ACSL4 expression in myeloma cells are both associated with worse clinical outcomes for MM patients. Cancer Dependency Map (DepMap) data showed that all five ACSLs have negative Chronos scores, and ACSL3 and ACSL4 were among the top 25% Hallmark Fatty Acid Metabolism genes that support myeloma cell line fitness. Inhibition of ACSLs in myeloma cell lines in vitro, using the pharmacological inhibitor Triacsin C (TriC), increased apoptosis, decreased proliferation, and decreased cell viability, in a dose- and time-dependent manner. RNA-sequencing analysis of MM.1S cells treated with TriC showed a significant enrichment in apoptosis, ferroptosis, and endoplasmic reticulum (ER) stress, and proteomic analysis of these cells revealed enriched pathways for mitochondrial dysfunction and oxidative phosphorylation. TriC also rewired mitochondrial metabolism by decreasing mitochondrial membrane potential, increasing mitochondrial superoxide levels, decreasing mitochondrial ATP production rates, and impairing cellular respiration. Overall, our data support the hypothesis that suppression of ACSLs in myeloma cells is a novel metabolic target in MM that inhibits their viability, implicating this family as a promising therapeutic target in treating myeloma.

The Host Adaptation of Staphylococcus aureus to Farmed Ruminants in New Zealand, With Special Reference to Clonal Complex 1

Genetic features of host adaptation of S. aureus to ruminants have been extensively studied, but the extent to which this adaptation occurs in nature remains unknown. In New Zealand, clonal complex 1 (CC1) is among the most common lineages in humans and the dominant lineage in cattle, enabling between-, and within-CC genomic comparisons of epidemiologically cohesive samples of isolates. We assessed the following genomic benchmarks of host adaptation to ruminants in 277 S. aureus from cattle, small ruminants, humans, and pets: 1, phylogenetic clustering of ruminant strains; 2, abundance of homo-specific ruminant-adaptive factors, and 3, scarcity of heterospecific factors. The genomic comparisons were complemented by comparative analyses of the metabolism of carbon sources that abound in ruminant milk. We identified features fulfilling the three benchmarks in virtually all ruminant isolates, including CC1. Data suggest the virulomes adapt to the ruminant niche sensu lato accross CCs. CC1 forms a ruminant-adapted clade that appears better equipped to utilise milk carbon sources than human CC1. Strain flow across the human-ruminant interface appears to only occur occasionally. Taken together, the results suggest a specialisation, rather than mere adaptation, clarifying why zoonotic and zoo-anthroponotic S. aureus transmission between ruminants and humans has hardly ever been reported.

Whole genome sequencing and phylogenetic analyses of the Sillaginidae family fish

For a long time, the taxonomic study of the Sillaginidae family of fish has been relatively slow, leaving the evolutionary relationships among species unclear. Previous research has mainly relied on morphological characteristics, with molecular studies limited primarily to mitochondrial genomics, including analyses of gene fragments and whole mitochondrial genomic sequence. This approach resulted in less precise and comprehensive species identification. In this study, we employed high-depth whole-genome sequencing (WGS) and genome surveys on 13 specimens representing 9 species of Sillaginidae fish collected from the wild. Our analysis included a thorough genomic survey and the assembly of draft genomes for each specimen. The genome sizes of Sillaginidae species are highly similar, ranging from 511.71 Mb to 578.27 Mb, with most individuals exhibiting repeat sequences content below 34.69 %. After the genome draft assembly of each sample, we identified conserved genes and shared consistent sequences among individuals and constructed a species phylogenetic tree based on these data. The results revealed that Sillago ingenua occupies the basal branch, followed by S. maculata and S. aeolus, then Sillaginopsis panijus, S. japonica and S. asiatica, and finally S. nigrofasciata and S. cf. sihama. Subsequently, we validated the phylogenetic tree using genome-wide single nucleotide variations, and the results were highly consistent. This research provides, for the first time, a whole-genome perspective on the evolutionary relationships among Sillaginidae species, offering valuable insights into their taxonomy and historical evolution.

Novel island species elucidate a species complex of Neotropical crocodiles

The evolutionary history of Neotropical crocodiles has remained elusive. They inhabit a broad geographic range with populations spanning from coastal, inland, and insular locations. Using a selection of natural insular, coastal, and one inland population of C. acutus, coastal C. moreletii, and the single surviving population of C. rhombifer, we discovered a remarkable genetic diversity for the group. Moreover, geometric morphometric results of skull shapes shows that these crocodylus species span a morphological cline. We recovered a high genetic differentiation between C. moreletii, C. rhombifer, and five clusters of C. acutus. The genetic and geographic differences among the C. acutus clusters were used to suggest these may be a species complex. Several ecological, morphological and genetics traits are identified in the well-studied populations from Banco Chinchorro and Cozumel islands off the Mexican Yucatan Peninsula to support discrete species designations for these populations. This work suggests the presence of rapid, recent evolution of several cryptic Crocodylus species throughout the Neotropics.

Ecotype-specific phenolic acid accumulation and root softness in Salvia miltiorrhiza are driven by environmental and genetic factors

Salvia miltiorrhiza Bunge, a renowned medicinal herb in traditional Chinese medicine, displays distinctive root texture and high phenolic acid content, traits influenced by genetic and environmental factors. However, the underlying regulatory networks remain unclear. Here, we performed multi-omics analyses on ecotypes from four major Chinese regions, focusing on environmental impacts on root structure, phenolic acid accumulation and lignin composition. Lower temperatures and increased UV-B radiation were associated with elevated rosmarinic acid (RA) and salvianolic acid B (SAB) levels, particularly in the Sichuan ecotype. Structural models indicated that the radial arrangement of xylem conduits contributes to greater root hardness. Genomic assembly and comparative analysis of the Sichuan ecotype revealed a unique phenolic acid metabolism gene cluster, including SmWRKY40, a WRKY transcription factor essential for RA and SAB biosynthesis. Overexpression of SmWRKY40 enhanced phenolic acid levels and lignin content, whereas its knockout reduced root hardness. Integrating high-throughput (DNA affinity purification sequencing) and point-to-point (Yeast One-Hybrid, Dual-Luciferase and Electrophoretic Mobility Shift Assay) protein-DNA interaction detection platform further identified SmWRKY40 binding sites across ecotypes, revealing specific regulatory networks. Our findings provide insights into the molecular basis of root texture and bioactive compound accumulation, advancing breeding strategies for quality improvement in S. miltiorrhiza.

Reutericyclin mitigates risperidone-induced suppression of anaerobic energy expenditure

Recent studies from our laboratory demonstrated that the gut microbial community represents a thermogenic biomass, as cecectomy causes an ∼8% decrease in total energy expenditure (EE) via suppression of anaerobic EE. The composition of the microbial community also dictates the EE of the microbial biomass as treatment with the antipsychotic, risperidone, suppresses anaerobic EE in a microbiome-dependent manner. Finally, we have determined that a specialized metabolite produced by Limosilactobacillus reuteri, reutericyclin (RTC), opposes the weight-gain effects of risperidone. In the present study, we performed comprehensive evaluations of energy balance in female C57BL/6J mice treated with risperidone, RTC, or both, to identify mechanisms by which RTC affects energy balance to mitigate risperidone-induced weight gain. We observed that risperidone suppressed anaerobic EE, and that RTC coadministration ameliorated the anaerobic EE suppression and weight gain induced by risperidone. Because anaerobic EE is dependent on the gut microbiota, we performed 16S and whole genome shotgun sequencing on stool and cecal samples following whole animal calorimetry. Risperidone and RTC treatments reciprocally modified the relative abundance of taxa known to participate in fermentation, especially for the production of short-chain fatty acids, which have been correlated with health and leanness in both humans and mice. Together, our data demonstrate that treatment with RTC positively modulates anaerobic EE, possibly by enhancing fermentation of the gut microbial community, and may represent a novel therapeutic in the treatment of obesity.NEW & NOTEWORTHY The gut microbial community represents a thermogenic biomass. The composition of the microbial community dictates energy expenditure of the microbial biomass and is altered by xenobiotics and bacterial metabolites. This study demonstrates that treatment with reutericyclin positively modulates anaerobic energy expenditure and may represent a novel therapeutic in the treatment of obesity.

Mild and ultrafast GLORI enables absolute quantification of m6A methylome from low-input samples

Methods for absolute quantification of N6-methyladenosine (m6A) have emerged as powerful tools in epitranscriptomics. We previously reported GLORI, a chemical-assisted approach to achieve unbiased and precise m6A measurement. However, its lengthy reaction time and severe RNA degradation have limited its applicability, particularly for low-input samples. Here, we present two updated GLORI approaches that are ultrafast, mild and enable absolute m6A quantification from one to two orders of magnitude less than the RNA starting material: GLORI 2.0 is compatible with RNA from ~10,000 cells and enhances sensitivity for both transcriptome-wide and locus-specific m6A detection; GLORI 3.0 further utilizes a reverse transcription-silent carrier RNA to achieve m6A quantification from as low as 500-1,000 cells. Using limited RNA from mouse dorsal hippocampus, we reveal a high modification level in synapse-related gene sets. We envision that the updated GLORI methods will greatly expand the applicability of absolute quantification of m6A in biology.

METTL14-Induced M6A Methylation Increases G6pc Biosynthesis, Hepatic Glucose Production and Metabolic Disorders in Obesity

METTL14 dimerizes with METTL3 to install N6-methyladenosine (m6A) on mRNA (m6A writers). Subsequently, m6A readers bind to m6A-marked RNA to influence its metabolism. RNA m6A emerges to critically regulate multiple intracellular processes; however, there is a gap in our understanding of m6A in liver metabolism. Glucose-6-phosphatase catalytic subunit (G6pc) mediates hepatic glucose production (HGP) and serves as the gatekeeper for glycogenolysis and gluconeogenesis; however, G6pc regulation is not fully understood. Here, METTL14 is identified as a posttranscriptional regulator of G6pc. Liver METTL14, METTL3, and m6A-methylated G6pc mRNA are upregulated in mice with diet-induced obesity. Deletion of Mettl14 decreases, whereas overexpression of METTL14 increases, G6pc mRNA m6A in hepatocytes in vitro and in vivo. Five m6A sites are identified, and disruption of them (G6pcΔ 5A) blocks METTL14-induced m6A methylation of G6pcΔ 5A mRNA. METTL14 increases both stability and translation of G6pc but not G6pcΔ 5A mRNA. YTHDF1 and YTHDF3 but not YTHDF2 (m6A readers) bind to m6A-marked G6pc mRNA to increase its synthesis. Deletion of hepatic Mettl14 decreases gluconeogenesis in primary hepatocytes, liver slices, and mice. Hepatocyte-specific restoration of G6pc reverses defective HGP in Mettl14 knockout mice. These results unveil a METTL14/G6pc mRNA m6A/G6pc biosynthesis/HGP axis governing glucose metabolism in health and metabolic disease.

VariantFoldRNA: a flexible, containerized, and scalable pipeline for genome-wide riboSNitch prediction

Single nucleotide polymorphisms (SNPs) can alter RNA structure by changing the proportions of existing conformations or leading to new conformations in the structural ensemble. Such structure-changing SNPs, or riboSNitches, have been associated with diseases in humans and climate adaptation in plants. While several computational tools are available for predicting whether an SNP is a riboSNitch, these tools were generally developed to analyze individual RNAs and are not optimized for genome-wide analyses. To fill this gap, we developed VariantFoldRNA, a flexible, containerized, and automated pipeline for genome-wide prediction of riboSNitches. Our pipeline automatically installs all dependencies, can be run locally or on high-performance clusters, and is modular, enabling the user to customize the analysis for the research question of interest. VariantFoldRNA can predict riboSNitches genome-wide at user-specified temperatures and splicing conditions, opening the door to novel analyses. The pipeline is an open-source command-line tool that is freely available at https://github.com/The-Bevilacqua-Lab/variantfoldrna.

Tracking Antimicrobial Resistant Organisms Timely: a workflow validation study for successive core-genome SNP-based nosocomial transmission analysis

Background and Objectives

Effective infection prevention and control (IPC) interventions in hospitals require timely information to determine the potential transmission of antimicrobial-resistant (AMR) organisms. We proposed and developed a successive core-genome SNP (cgSNP)-based phylogenetic analysis workflow, 'Tracking Antimicrobial Resistant Organisms Timely' (TAROT), using the Oxford Nanopore Technologies (ONT) sequencer for MRSA, and compared the results with those obtained using the Illumina sequencer.

Methods

We have developed a TAROT workflow for successive phylogenetic analysis using ONT data. We sequenced 34 MRSA strains isolated from Toho University Omori Medical Center using MinION (ONT) and MiSeq (Illumina). Each strain's ONT data were inputted into TAROT (TAROT-ONT), and successive cgSNP-based phylogenetic analyses were conducted. Illumina data were processed with a batched cgSNP-based phylogenetic analysis. Assembly-based analysis identified AMR genes, AMR mutations and virulence genes.

Results

MinION generated an average sequence depth of 262× for the ST8 reference genome within 3 h. TAROT-ONT successively generated 11 phylogenetic trees for 14 ST8 strains, 7 trees for 10 ST1 strains and 2 trees for 5 ST5 strains. Highly suspected transmission pairs (pairwise cgSNP< 5) were detected in trees #6 through #11 for ST8, trees #3, #5 and #7 for ST1, and tree #2 for ST5. Differences in pairwise cgSNP value between TAROT-ONT and Illumina ranged from zero to two within pairs with fewer than 20 cgSNPs using Illumina. TAROT-ONT bioinformatic analysis for each strain required 5-42 min. The identification of AMR genes, mutations and virulence genes showed high concordance between ONT and Illumina.

Conclusions

TAROT-ONT can facilitate effective IPC intervention for MRSA nosocomial transmissions by providing timely feedback through successive phylogenetic analyses based on cgSNPs.

Defining molecular signatures of the solid/pseudopapillary and pseudoglandular patterns in so-called "solid-tubulocystic intrahepatic cholangiocarcinoma vs. NIPBL::NACC1 fusion hepatic carcinoma"

Solid-tubulocystic variant of intrahepatic cholangiocarcinoma (ST-iCCA) is newly described entity characterized by two distinct histologic growth patterns: (1) solid sheets of tumor cells with focal necrosis giving pseudopapillary appearance and (2) tubular or pseudoglandular structures containing pink, colloid-like material. Tumor cells are inhibin-positive and harbor NIPBL::NACC1 fusion gene. To date, only 28 cases of ST-iCCA have been documented. While prior molecular studies provided insights into ST-iCCA, genetic profiles of individual histologic components have not been explored. This study presents first transcriptomic analysis comparing the solid/pseudopapillary and pseudoglandular components of ST-iCCA. Two cases of histologically confirmed ST-iCCA were identified for RNA sequencing which was performed on solid/pseudopapillary component, pseudoglandular component, and normal tissue. Analysis revealed distinct gene expression profiles for each pattern. Solid/pseudopapillary component uniquely overexpressed DMRTA1, NEXMIF, PRDM6, SORCS3, and NALF, while pseudoglandular component exhibited unique overexpression of HRG, ITIH3, TAT, APOA2, CP, ALDOB, CPS1, F2, KHG1, SERPINC1, HPX, C9, ADGRF1, MUC21, SAA2, SPRR2A, SAA1, FGL1, CFHR1, and LBP. These findings establish unique gene signatures for these variants of ST-iCCA, providing potential biomarkers for differential diagnosis, prognosis and targeted therapy. The distinct genetic profiles may also uncover novel therapeutic targets to address the aggressive nature of ST-iCCA.

Molecular clock complexities of Clostridioides difficile

OBJECTIVES

Reconstruct the phylogenetic status of a collection of historical Clostridioides difficile isolates and evaluate the congruence of their evolutionary trajectories with established molecular clock models.

METHODS

Phylogenetic analysis was performed on Illumina sequence reads from previously analysed historic C. difficile isolates (1980-86; n = 75) demonstrating multiple antimicrobial resistances. Data was grouped by ribotype (RT), including comparators from European surveillance (2012-13) and phylogenetic studies (1985-2010). Reads were mapped to CD630/CD196 reference genomes and compared using recombination-adjusted maximum likelihood trees. Prediction intervals for expected SNP differences by age were calculated using a Poisson distribution and molecular clock estimates (0.74 SNPs per genome/per year). Root-to-tip analysis was performed to determine the date of most common recent ancestor of genomes sharing a ribotype.

RESULTS

Moxifloxacin-resistant (>16 mg/L) RT027 isolate JV67 (1986) was two SNPs distinct from a 2006 genome, fewer than the expected lower estimate (4.4 SNPs) under current molecular clock calculations; (p = 3.93x10-5). For isolate JV02 (1981), the 13 SNP divergence from a 2008 isolate was consistent with expectations (5.9 SNPs; p = 0.07). JV73 (1983) demonstrated an 8 SNP difference, which although above the expected lower limit (5.5 SNPs), was outside the 95 % prediction interval; (p = 4.51x10-3). Only sixty-nine percent of historical genomes fit within the prediction interval for the number of SNPs expected compared to recent isolates, with fewer SNPs observed more frequently than expected. Root-to-tip analysis demonstrated a weak linear correlation.

CONCLUSIONS

C. difficile molecular clock estimations may be more complex than previously considered, with periods of spore quiescence potentially complicating analyses.

Haplotype-resolved genome assembly and genome-wide association study identifies the candidate gene closely related to sugar content and tuber yield in Solanum tuberosum

As an important noncereal food crop grown worldwide, the genetic improvement of potato in tuber yield and quality is largely constrained due to the lacking of a high-quality reference genome and understanding of the regulatory mechanism underlying the formation of superior alleles. Here, a chromosome-scale haplotype-resolved genome assembled from an anther-cultured progeny of 'Ningshu 15', a tetraploid variety featured by its high starch content and drought resistance was presented. The assembled genome size was 1.653 Gb, with a contig N50 of approximately 1.4 Mb and a scaffold N50 of 61 Mb. The long terminal repeat assembly index score of the two identified haplotypes of 'Ningshu 15' was 11.62 and 11.94, respectively. Comparative genomic analysis revealed that positive selection occurred in gene families related to starch, sucrose, fructose and mannose metabolism, and carotenoid biosynthesis. Further genome-wide association study in 141 accessions identified a total number of 53 quantitative trait loci related to fructose, glucose, and sucrose content. Among them, a tonoplast sugar transporter encoding gene, StTST2, closely associated with glucose content was identified. Constitutive expression of StTST2 in potato and Arabidopsis increased the photosynthetic rate, chlorophyll and sugar content, biomass tuber and seed production in transgenic plants. In addition, co-immunoprecipitation assays demonstrated that StTST2 directly interacted with SUT2. Our study provides a high-quality genome assembly and new genetic locus of potato for molecular breeding.

Identification of molecular signatures for azole fungicide toxicity in zebrafish embryos by integrating transcriptomics and gene network analysis

Azoles control fungal growth by inhibiting sterol biosynthesis in fungi according to the fungicide resistance action committee. Furthermore, previous studies have highlighted several effects of azole fungicides in fish including endocrine disruption. In this study, we analysed the transcriptome responses of zebrafish embryos exposed to azole fungicides to identify gene expression fingerprints indicating toxic effects such as endocrine disruption induced by sterol biosynthesis inhibition. Firstly, a modified zebrafish embryo toxicity test was conducted following the OECD 236 guideline, exposing embryos to difenoconazole, epoxiconazole, and tebuconazole. After 96 h, RNA was extracted for transcriptome analysis, which revealed concentration-dependent responses for each fungicide. Additionally, overrepresentation analysis of significantly differentially expressed genes revealed biological functions related to sterol biosynthesis and endocrine disruption. A gene set with specific expression patterns was was identified as molecular signature for indicating adverse effects induced by sterol biosynthesis inhibitors in zebrafish embryos. After further validation, the gene expression fingerprints and biomarkers identified in this study may be used in the future to identify endocrine activity of substances under development in a pre-regulatory screening using the zebrafish embryo model.

Tracking Particle-Encapsulated DNA Across the Anion-Exchange Chromatography Fractions of Recombinant Adeno-Associated Virus Using Droplet Digital PCR and High-Throughput Sequencing

INTRODUCTION

Safe and effective adeno-associated virus (AAV) vectors are essential for gene therapy. Particle heterogeneity, specifically particle DNA of varying types and sizes, significantly affects recombinant adeno-associated virus (rAAV) performance. Previous studies have identified particle-associated DNAs; however, the specific DNA composition of these mixed populations remains poorly understood. This study aimed to investigate the DNA composition of the isolated subpopulations of rAAV particles obtained through anion exchange (AEX) chromatography.

METHODS

RAAV2-ZsGreen1 particles were fractionated on an AEX column, resulting in 12 distinct fractions. We analyzed the DNA composition of these fractions using droplet digital PCR (ddPCR) and MiSeq to identify the incorporated DNA heterogeneity in them.

RESULTS

Our findings illustrated a clear trend in which the DNA content increasing in fractions was associated with an increased rAAV genomic DNA ratio of total particle DNA. The particle DNA content increased significantly across fractions from Peak 1 to Peak 2, showing approximately 30,000- and 5000-fold increases for ZsGreen1 (rAAV genome) and ampR (plasmid impurity), respectively. Notably, in the empty particle subpopulations, the rate of detectable DNA molecules was lower than one DNA fragment per 100 particles, with inverted terminal repeat (ITR) sequences being the most prevalent.

CONCLUSIONS

With the elucidated profile of particle DNAs, this study provides detailed information on particle heterogeneity, shedding light on empty and partial particle formation and impurity DNA incorporation.

Mitochondrial metabolism sustains DNMT3A-R882-mutant clonal haematopoiesis

Somatic DNMT3A-R882 codon mutations drive the most common form of clonal haematopoiesis (CH) and are associated with increased acute myeloid leukaemia (AML) risk1,2. Preventing expansion of DNMT3A-R882-mutant haematopoietic stem/progenitor cells (HSPCs) may therefore avert progression to AML. To identify DNMT3A-R882-mutant-specific vulnerabilities, we conducted a genome-wide CRISPR screen on primary mouse Dnmt3aR882H/+ HSPCs. Among the 640 vulnerability genes identified, many were involved in mitochondrial metabolism, and metabolic flux analysis confirmed enhanced oxidative phosphorylation use in Dnmt3aR882H/+ versus Dnmt3a+/+ (WT) HSPCs. We selected citrate/malate transporter Slc25a1 and complex I component Ndufb11, for which pharmacological inhibitors are available, for downstream studies. In vivo administration of SLC25A1 inhibitor CTPI2 and complex I inhibitors IACS-010759 and metformin suppressed post-transplantation clonal expansion of Dnmt3aR882H/+, but not WT, long-term haematopoietic stem cells. The effect of metformin was recapitulated using a primary human DNMT3A-R882 CH sample. Notably, analysis of 412,234 UK Biobank participants showed that individuals taking metformin had a markedly lower prevalence of DNMT3A-R882-mutant CH, after controlling for potential confounders including glycated haemoglobin, diabetes and body mass index. Collectively, our data propose modulation of mitochondrial metabolism as a therapeutic strategy for prevention of DNMT3A-R882-mutant AML.

Metagenomics-based tracing of genetically modified microorganism contaminations in commercial fermentation products

Genetically modified microorganisms (GMM) are frequently employed for the production of microbial fermentation products such as food enzymes. Although presence of the GMM or its recombinant DNA in the final product is not authorized, contaminations occur frequently. Insight into the contamination source of a GMM is of crucial importance to allow the competent authorities to take appropriate action. The aim of this study was to explore the feasibility of a metagenomic shotgun sequencing approach to investigate microbial contamination in fermentation products, focusing on source tracing of GMM strains using innovative strain deconvolution and phylogenomic approaches. In most cases, analysis of 16 GMM-contaminated food enzyme products supported finding the same GM producer strains in different products, while often multiple GMM contaminations per product were detected. Presence of AMR genes in the samples was strongly associated with GMM contamination, emphasizing the potential public health risk. Additionally, a variety of other microbial contaminations were detected, identifying a group of samples with a conspicuously similar contamination profile, which suggested that these samples originated from the same production facility or batch. Together, these findings highlight the need for guidelines and quality control for traceability of these products to ensure the safety of consumers. This study demonstrates the added value of metagenomics to obtain insight in the microbial contamination profiles, as well as their underlying relationships, in commercial microbial fermentation products. The proposed approach may be applied to other types of microbial fermentation products and/or to other (genetically modified) producer strains.

Genome-wide locus-allele comparison reveals differential evolution dynamics from annual wild to landrace and released cultivar soybeans

Previous studies on population evolution relied primarily on allele frequency analysis using molecular markers or genome sequence segments, like selective sweeps. With the sequencing technique developed, we suggest the genome-wide locus-allele comparison to detect the genomic structure variation among populations. Its key point lies in taking SNP linkage disequilibrium block as uniform genomic marker for genome-wide gene and inter-gene regions to meet the requirement of multiple alleles in natural populations. A sample composed of 750 annual wild accessions (WAs), landraces (LRs), and released cultivars (RCs) of soybean from southern, northern, and northeastern China eco-regions (SC, NC, and NEC, respectively) were analyzed for their evolution dynamics involving four evolutionary processes (WA→LR→RC, WASC→WANC→WANEC, LRSC→LRNC→LRNEC, and LRSC→RCSC/LRNC→RCNC/LRNEC→RCNEC). Our major finding was the discovery of allele and locus zero/one variation between/among ancestor-filial populations involving a large part of the whole population alleles and loci, 25.10% and 18.62% in domestication and modern breeding stages, respectively, which was not detected by selective sweeps. The essence of population evolution is the allele zero/one changes based on ordinary allele frequency changes, which causes the locus zero/one changes. The allele/locus zero/one variation happened more often when their frequency was at 0.0-0.3 and 0.8-0.99 in the previous stage generation, respectively. The WA and LR geographic evolution are different processes due to different combination of allele/locus zero/one changes by natural versus artificial selection pressures. Compared to per-year allele exclusion, the rate of per-year allele emergence is relatively stable in domestication and modern breeding (2.75E-5 vs. 1.34E-5 and 1.42E-3 vs. 1.10E-5), respectively.

RIG-I-driven CDKN1A stabilization reinforces cellular senescence

The innate immune signaling network follows a canonical format for signal transmission. The innate immune pathway is crucial for defense against pathogens, yet its mechanistic crosstalk with aging processes remains largely unexplored. Retinoic acid-inducible gene-I (RIG-I), a key mediator of antiviral immunity within this pathway, has an enigmatic role in stem cell senescence. Our study reveals that RIG-I levels increase in human genetic and physiological cellular aging models, and its accumulation drives cellular senescence. Conversely, CRISPR/Cas9-mediated RIG-I deletion or pharmacological inhibition in human mesenchymal stem cells (hMSCs) confers resistance to senescence. Mechanistically, RIG-I binds to endogenous mRNAs, with CDKN1A mRNA being a prominent target. Specifically, RIG-I stabilizes CDKN1A mRNA, resulting in elevated CDKN1A transcript levels and increased p21Cip1 protein expression, which precipitates senescence. Collectively, our findings establish RIG-I as a post-transcriptional regulator of senescence and suggest potential targets for the mitigation of aging-related diseases.

Deciphering the complex molecular architecture of the genetically modified soybean FG72 through paired-end whole genome sequencing

The clear molecular characterization of genetically modified (GM) plants and animals is a prerequisite for obtaining regulatory approval and safety certification for commercial cultivation. This characterization includes the identification of the transferred DNA (T-DNA) insertion site, its flanking sequences, the copy number of inserted genes, and the detection of any unintended genomic alterations accompanying the transformation process. In this study, we performed a comprehensive molecular characterization of the well-known GM soybean event FG72 using paired-end whole-genome sequencing (PE-WGS). We examined the T-DNA insertion site, flanking sequences, the entire structure and copy number of the T-DNA integration, the presence of plasmid backbone sequences, and genome-wide structural variations (SVs). Our analysis revealed that the T-DNA integrated into two distinct sites on chromosome 15 of the host genome, accompanied by a translocation of host genomic sequences. One site harbored a partial T-DNA integration, while the other site contained two tandem repeats of the full T-DNA. Importantly, no plasmid backbone sequences were detected in the host genome, indicating a clean T-DNA integration during the biolistic transformation process. Furthermore, we identified numerous genome-wide SVs, with chromosome 15 ranking second among all 20 chromosomes in terms of SV frequency, and most of these variations occurring within gene-coding regions. These results provide a refined and comprehensive molecular characterization of the FG72 soybean event, which could further support its commercial approval and cultivation. Our work highlights the utility of the PE-WGS approach as a sensitive and labor-efficient alternative to conventional molecular characterization techniques, generating comprehensive data to facilitate the safety assessment of GM crops during research and commercialization pipelines.

The impact of human dispersals and local interactions on the genetic diversity of coastal Papua New Guinea over the past 2,500 years

The inhabitants of New Guinea and its outlying islands have played an important role in the human history of the Pacific region. Nevertheless, the genetic diversity, particularly of pre-colonial communities, is still understudied. Here we present the ancient genomes of 42 individuals from Papua New Guinea (PNG). The ancient genomic results of individuals from Watom Island (Bismarck Archipelago) and the south and northeastern coasts of PNG are contextualized with new (bio-) archaeological data. The individuals' accelerator mass spectrometry (AMS) dates span 2,500 years of human habitation, and our results demonstrate the influences of different dispersal events on the genetic make-up of ancient PNG communities. The oldest individuals show an unadmixed Papuan-related genetic signature, whereas individuals dating from 2,100 years before present carry varying degrees of an East-Asian-related contribution. These results and the inferred admixture dates suggest a centuries-long delay in genetic mixture with local communities after the arrival of populations with Asian ancestry. Two geographically close communities on the South Coast, AMS dated to within the past 540 years, diverge in their genetic profiles, suggesting differences in their interaction spheres involving groups with distinct ancestries. The inferred split time of these communities around 650 years before present coincides with intensified settlement activity and the emergence of regional trade networks.

Base editing of trinucleotide repeats that cause Huntington's disease and Friedreich's ataxia reduces somatic repeat expansions in patient cells and in mice

Trinucleotide repeat (TNR) diseases are neurological disorders caused by expanded genomic TNRs that become unstable in a length-dependent manner. The CAG•CTG sequence is found in approximately one-third of pathogenic TNR loci, including the HTT gene that causes Huntington's disease. Friedreich's ataxia, the most prevalent hereditary ataxia, results from GAA repeat expansion at the FXN gene. Here we used cytosine and adenine base editing to reduce the repetitiveness of TNRs in patient cells and in mice. Base editors introduced G•C>A•T and A•T>G•C interruptions at CAG and GAA repeats, mimicking stable, nonpathogenic alleles that naturally occur in people. AAV9 delivery of optimized base editors in Htt.Q111 Huntington's disease and YG8s Friedreich's ataxia mice resulted in efficient editing in transduced tissues, and significantly reduced repeat expansion in the central nervous system. These findings demonstrate that introducing interruptions in pathogenic TNRs can mitigate a key neurological feature of TNR diseases in vivo.

Operationalizing SARS-CoV-2 wastewater monitoring to assess traveler health in Las Vegas, Nevada, USA

Objectives

This study explored expanded traveler- and tourism-focused wastewater monitoring in Las Vegas, Nevada, USA to complement community SARS-CoV-2 surveillance.

Methods

Wastewater samples were collected November 2023 to July 2024 from the largest community-scale wastewater treatment plant in Southern Nevada, USA (N = 112 samples) and two upstream utility access holes (i.e. manholes), isolating an international airport (N = 68 samples) and a commercial area with high-density bars and nightclubs (N = 30-33 samples). Polymerase chain reaction-based methods quantified RNA concentrations of SARS-CoV-2 and pepper mild mottle virus; whole genome sequencing characterized SARS-CoV-2 variants (N = 83 qualifying samples).

Results

SARS-CoV-2 concentrations exhibited concordance between liquids- and solids-based approaches. Similar trends were observed between methods and sampling locations; however, select manhole-level findings suggested potentially divergent COVID-19 infection profiles relative to residents. Whole genome sequencing also demonstrated similarities across sampling locations, although airport samples facilitated the identification of SARS-CoV-2 variants that either failed to spread locally (EG.6, JN.1.11) or preceded detection at the wastewater treatment plant (JN.1.7, KP.3).

Conclusions

These findings offer new insight into the operationalization of broader traveler- and tourism-focused wastewater monitoring, which may capture SARS-CoV-2 concentration spikes and genomic profiles in high-tourism/nightlife areas that community-scale sampling might otherwise miss.

Analysis of genetic diversity and selection signatures on the Zhashi Brown goat through whole genome sequencing data

The Zhashi Brown goat is native to Hengyang Municipality in Hunan Province in southern China and boasts a rich history. The goats exhibit exceptional traits, including heat and insect resistance, strong reproductive capabilities and superior meat production. Despite these merits, the currently limited population requires immediate conservation endeavors. In this study, we conducted whole-genome resequencing on 21 Zhashi Brown goats. Additionally, we performed a joint analysis using published whole-genome data from 119 goats, including Chengdu Brown goat, Matou goat, Wuxue goat, Xiangdong Black goat, Qaidam Cashmere goat, Ujumqin Cashmere goat and Shanbei Cashmere goat. The results revealed that the Zhashi Brown goat is genetically more pure than other Southern Chinese goat breeds. Furthermore, the genetic diversity (nucleotide diversity, linkage disequilibrium, runs of homozygosity and inbreeding coefficient) of the Zhashi Brown goat's genome is at a low level among the eight breeds, indicating the need for further conservation. Employing analytical methodologies such as composite likelihood ratio, nucleotide diversity, integrated haplotype score, the fixation index and cross-population extended haplotype homozygosity, we systematically scanned selective signals within the genomic landscape of Zhashi Brown goat. The outcomes underscore strong selection signals associated with genes implicated in immune response, heat tolerance, reproductive performance and meat quality. These findings make a significant contribution to our understanding of the genetics framework associated with adaptive traits in Zhashi Brown goat. Furthermore, this study explores the genetic diversity of the Zhashi Brown goat, which may contribute to the theoretical framework for conserving its genetic resources, while the identified trait-associated variations could inform future strategies to optimize selective breeding programs.

Analysis of the genetic diversity of the soybean rust pathogen Phakopsora pachyrhizi reveals two major evolutionary lineages

Phakopsora pachyrhizi, an obligate biotrophic rust fungus, is the causal agent of Asian Soybean Rust (ASR) disease. Here, we utilized whole-genome data to explore the evolutionary patterns and population structure across 45 P. pachyrhizi isolates collected from 1972 to 2017 from diverse geographic regions worldwide. We also characterized in-silico mating-type (MAT) genes of P. pachyrhizi, in the predicted proteome of three isolates, to investigate the sexual compatibility system. Our molecular phylogenetic analysis in P. pachyrhizi inferred two distinct evolutionary lineages structured on a temporal scale, with lineage Pp1 grouping isolates obtained from 1972 to 1994, while more recently collected isolates formed a second lineage, Pp2. We found higher levels of genetic diversity in lineage Pp1, whereas lineage Pp2 exhibited a strong clonal genetic structure, with a significant lower diversity. The widespread propagation of P. pachyrhizi clonal spores across soybean-growing regions likely explains the absence of a large-scale spatial genetic structure within each lineage. Two independent isolates (TW72-1 and AU79-1) showed moderate levels of genetic admixture, suggesting potential somatic hybridization between the two P. pachyrhizi lineages. We observed no clear congruence between virulence levels of P. pachyrhizi isolates and their phylogenetic patterns. Our findings support a probable tetrapolar mating system in P. pachyrhizi. Taken together, our study offers new insights into the evolutionary history of P. pachyrhizi and demonstrates that multiple MAT genes are highly expressed during the later stages of soybean infection, suggesting their potential role in the formation of urediniospores within the life cycle of P. pachyrhizi.

Interleukin-10 production by innate lymphoid cells restricts intestinal inflammation in mice

Interleukin-10 (IL-10) is an immunomodulatory cytokine critical for intestinal immune homeostasis. IL-10 is produced by various immune cells but IL-10 receptor signaling in intestinal CX3CR1+ mononuclear phagocytes is necessary to prevent spontaneous colitis in mice. Here, we utilized fluorescent protein reporters and cell-specific targeting and found that Rorc-expressing innate lymphoid cells (ILCs) produce IL-10 in response to anti-CD40-mediated intestinal inflammation. Deletion of Il10 specifically in Rorc-expressing ILCs led to phenotypic changes in intestinal macrophages and exacerbated both innate and adaptive immune-mediated models of experimental colitis. The population of IL-10+ producing ILCs shared markers with both ILC2 and ILC3 with nearly all ILC3s being of the NCR+ subtype. Interestingly, Ccl26 was enriched in IL-10+ ILCs and was markedly reduced in IL-10-deficient ILC3s. Since CCL26 is a ligand for CX3CR1, we employed RNA in situ hybridization and observed increased numbers of ILCs in close proximity to Cx3cr1-expressing cells under inflammatory conditions. Finally, we generated transgenic RorctdTomato reporter mice that faithfully marked RORγt+ cells that could rescue disease pathology and aberrant macrophage phenotype following adoptive transfer into mice with selective Il10 deficiency in ILC3s. These results demonstrate that IL-10 production by a population of ILCs functions to promote immune homeostasis in the intestine possibly via direct effects on intestinal macrophages.

Genetic insights into progressive myoclonic epilepsies: A case study of KCTD7 mutation in an Iranian-Azeri-Turkish family

Progressive Myoclonic Epilepsies (PMEs) are a rare and heterogeneous group of epileptic disorders often with progressive neurologic deterioration. The intensity of the clinical features varies depending on the underlying genetic etiology. This study aims to identify the genetic mutation associated with PME in a family belonging to the Iranian-Azeri-Turkish ethnic population. A 5-year-old boy and his 8-year-old sister, presenting with PME-related electroclinical features such as myoclonic seizures and progressive cognitive and motor decline, underwent comprehensive clinical evaluations, including pedigree analysis, laboratory tests, and EEG assessments, followed by Whole-Exome Sequencing (WES) to identify potential disease-causing mutations. We identified a novel homozygous mutation (c.14C > T) in the KCTD7 gene in both siblings, confirmed through Sanger sequencing. This mutation was not observed in a cohort of 430 healthy individuals from the same Iranian-Azeri-Turkish ethnic background, providing strong evidence for its pathogenic role. This finding advances our understanding of the genetic basis and phenotypic diversity of PMEs, but further research is needed to elucidate how KCTD7 mutations contribute to epilepsy and neurodegeneration.

Protocol for identifying genomic binding sites of mitotic bookmarkers in Drosophila neural stem cells and cultured mammalian cells

Mitotic bookmarkers label key gene loci on highly condensed chromosomes to preserve cell fate memory across mitosis. Here, we present a protocol for identifying binding sites of mitotic bookmarkers (BISMIBs) in developing tissues and cultured cells. We describe a workflow for isolating mitotic and interphase cells from Drosophila larval brains and HEK293T cells independent of cell-cycle synchronization. We further detail procedures for low-input in vivo CUT&Tag (Cleavage Under Targets & Tagmentation) sequencing. This protocol is applicable for identifying binding sites for mitotically retained factors in developing tissues. For complete details on the use and execution of this protocol, please refer to Shen et al.1.

Protocol for adaptive laboratory evolution of S. cerevisiae by PEG/LiAc transformation and sequencing

Gene deletions perturb cellular homeostasis, affecting gene expression and phenotypes. Here, we present a protocol for serial transfer experiments in Saccharomyces cerevisiae strains following targeted gene knockouts. We describe steps for gene deletion, serial passage optimization, and growth kinetics analysis. We then detail procedures for genomic and transcriptomic profiling. This protocol enables the investigation of changes in yeast strains resulting from gene loss. For complete details on the use and execution of this protocol, please refer to Jiang et al.1.

Eomesodermin in conjunction with the BAF complex promotes expansion and invasion of the trophectoderm lineage

The T-box transcription factor (TF) Eomesodermin/Tbr2 (Eomes) is essential for maintenance of the trophectoderm (TE) lineage, but the molecular mechanisms underlying this critical role remain obscure. Here, we show in trophoblast stem cells (TSCs) that Eomes partners with several TE-specific TFs as well as chromatin remodellers, including Brg1 and other subunits of the BAF complex. Degron-mediated Eomes protein depletion results in genome-wide loss of chromatin accessibility at TSC-specific loci. These overlap with a subset of sites that lose accessibility following Brg1 inhibition, suggesting that Eomes acts as a "doorstop" controlling TSC chromatin accessibility. Eomes depletion also causes transcriptional misregulation of TSC maintenance and early differentiation markers. An additional subset of Eomes-dependent genes encode intercellular/matricellular interaction and cytoskeletal components, likely explaining the implantation defects of Eomes-null embryos. Thus, Eomes promotes TE lineage maintenance by sustaining trophectoderm-specific chromatin accessibility, while promoting the gene regulatory networks that modulate expansion and cell behaviour during implantation.

varVAMP: degenerate primer design for tiled full genome sequencing and qPCR

Time- and cost-saving surveillance of viral pathogens is achieved by tiled sequencing in which a viral genome is amplified in overlapping PCR amplicons and qPCR. However, designing pan-specific primers for viral pathogens with high genomic variability represents a significant challenge. Here, we present a bioinformatics command-line tool, called varVAMP (variable virus amplicons), which addresses this issue. It relies on multiple sequence alignments of highly variable virus sequences and enables degenerate primer design for qPCR or tiled amplicon whole genome sequencing. We demonstrate the utility of varVAMP by designing and evaluating novel pan-specific primer schemes suitable for sequencing the genomes of SARS-CoV-2, Hepatitis E virus, rat Hepatitis E virus, Hepatitis A virus, Borna-disease-virus-1, and Poliovirus using clinical samples. Importantly, we also designed primers on the same input data using the software packages PrimalScheme and Olivar and showed that varVAMP minimizes primer mismatches most efficiently. Finally, we established highly sensitive and specific Poliovirus qPCR assays that could potentially simplify current Poliovirus surveillance. varVAMP is open-source and available through PyPI, UseGalaxy, Bioconda, and https://github.com/jonas-fuchs/varVAMP .

Significant impact of bleaching treatment on phage-host interaction dynamics in a full-scale wastewater treatment plant

The temporal dynamics of phage-host interactions within full-scale biological wastewater treatment (BWT) plants remain inadequately characterized. Here, we provide an in-depth investigation of viral and bacterial dynamics over a nine-year period in an activated sludge BWT plant, where bleach addition was applied to control sludge foaming. By conducting bioinformatic analyses on 98 metagenomic time-series samples, we reconstructed 3,486 bacterial genomes and 2,435 complete or near-complete viral genomes, which were classified into 361 bacterial and 889 viral clusters, respectively. Our results demonstrate that the primary bleaching event induced significant shifts in both bacterial and viral communities, as well as in virus-host interactions, as evidenced by alterations in bacteria-virus interaction networks and virus-to-host ratio dynamics. Following bleaching, the bacteria-virus network became less interconnected but more compartmentalized. Viral communities mirrored bacterial dynamics, indicating a strong coupling in phage-host interactions. Among the identified virus-host pairs, many exhibited a decelerating rise in viral abundance relative to host abundance, with virus-to-host ratios generally displaying a negative correlation with host abundance. This trend was particularly pronounced in virus-host pairs where viruses harbored integrase genes, indicative of temperate dynamics resembling a "Piggyback-the-Winner" model. Notably, the bleaching intervention appeared to induce a transition from lysogeny to lysis in viruses associated with some foaming-related bacterial species, suggesting a potential virus-involved indirect mechanism by which bleaching mitigates sludge foaming.

Global Whole-Genome Resequencing of Beef Cattle Reveals Characteristic Traits Related Genes in Pinan Cattle

Beef cattle breed improvement holds strategic significance in the livestock industry. Pinan cattle, developed through years of selective breeding in Xinye County, Henan Province, exhibit superior traits including thin skin, fine bone structure, rapid growth, high dressing percentage, excellent meat yield, and superior feed efficiency. However, research on the genetic characteristics of Pinan cattle remains in its infancy. In this study, we investigated population genetic diversity and positive selection signals in Pinang cattle based on whole-genome resequencing data. Using a selective sweep approach, we identified 98 candidate genes associated with growth, reproduction, and immunity, along with 13 high-confidence missense mutations, which may underlie key traits in this population. Based on the critical roles of the NDN and PARVA genes in reproduction and muscle development, the predominant T allele at the NDN c.581T > A and PARVA c.893T > A loci in the Pinan cattle population may partially explain their advantages in sexual precocity and rapid growth compared to other breeds or populations. This study provides an important theoretical basis for the genetic improvement of native beef cattle and lays a scientific foundation for further investigation into the growth and development mechanisms of Pinan cattle.

Whole-genome sequencing revealed genetic structure, patterns of selection and molecular identity card in "Yufen 1″ D line chickens

The "Yufen 1" D line (D) chicken is characterized by strong disease resistance and a high feed conversion rate as a newly bred line. There are few reports on D chicken. In order to investigate the genetic diversity, population structure and selection signals of the D chicken, this study analyzed the genome-wide data of 15 D line chickens and 11 publicly available Chinese indigenous chicken breeds, the red jungle fowls. The genetic diversity of the D chicken was significantly lower than that of the Chinese indigenous chicken breeds and the red jungle fowl, but the inbreeding coefficient (FROH) was lower. On the one hand, this may be due to the small size of the conserved population, and on the other hand, it suggests that the D line may have received artificial selection during the selection process. Population structure analysis revealed that the D chicken was separated from Chinese indigenous chicken breeds and red jungle fowl, and had a high degree of genetic differentiation from other non-D chicken populations, suggesting that the D chicken is a unique poultry genetic resource worthy of our subsequent enhanced protection and utilization. The selective sweep analysis revealed that the genes selected in the D chicken were mainly enriched in the Toll and Imd signaling pathway and the Gastric acid secretion signaling pathway, including REL, UBE2V1, KCNJ16, and SLC26A7, which might be related to the excellent traits of high disease resistance and high feed conversion ratio in D chicken. In addition, the constructed molecular identity card of D chickens can be used to identify the authenticity of D chickens. These results lay the foundation for further research, conservation, and breeding of "Yufen 1" D line chickens.

Identifying functional roles and pathways of shared mutations in canine solid tumors by whole-genome sequencing

Identifying genetic mutations contributing to solid tumors by altering the biological pathways related to tumor formation and development is essential for the development of targeted therapies. This study aimed to identify commonly mutated genes and altered pathways in canine solid tumors. Four dogs with different types of naturally occurring neoplasias (urothelial carcinoma, adenocarcinoma, rhabdomyosarcoma, and chondrosarcoma) were randomly selected and classified into carcinoma and sarcoma groups based on histopathological findings. Tumor tissues were analyzed using whole-genome sequencing, and significant variants shared within each tumor group were identified. Gene set enrichment analyses were conducted to compare the biological and functional pathways altered by the mutations in each carcinoma and sarcoma group. Forty-three and fifty-eight genes were identified in the carcinoma and sarcoma groups, respectively. Distinctions between the two tumor groups were noted for mutations related to tumor metastatic function. Mutations were identified in genes encoding cell adhesion molecules in the carcinoma group, whereas significant variations in extracellular matrix-related molecules were evident in the sarcoma group. This study revealed mutations and modified pathways associated with immune and tumor metastatic functions in canine carcinoma and sarcoma, indicating their significant relevance to the development and progression of each tumor group. Additionally, the distinctions indicated that different therapeutic approaches were required for each tumor group.

Genome-wide patterns of local adaptation associated with transposable elements in Tetrastigma hemsleyanum (Vitaceae)

The mobility of transposable elements (TEs) partly drives genome evolution, potentially leading to either adaptive or deleterious effects. However, it remains far from clear whether and how TEs contribute to adaptation to changing environments, especially in plants. We analyzed whole-genome sequencing data from 29 ecologically diverse Tetrastigma hemsleyanum populations to infer the species' demographic history and its impact on TE polymorphisms. Integrated selective sweep and genome-environment association (GEA) approaches were employed to examine the contribution of TEs to environmental adaptation. The ancestor of T. hemsleyanum diverged during the late Miocene/Pliocene, forming two lineages that further split into four sublineages. These (sub)lineages underwent periodic population declines and recoveries during the late-Pleistocene climatic oscillations, with most polymorphic TEs transposing during the last glacial period. A small fraction of these TEs (0.033-0.40%) showed signatures of positive selection, while a broader subset (0.081-0.76%) correlated significantly with climatic variables. Notably, these selected or climate-linked TE polymorphisms were preferentially retained in gene-poor regions and frequently linked to genes involved in organ development and stress/defense response. Our findings demonstrate that TEs played a key regulatory and adaptive role in T. hemsleyanum's response to environmental change, underscoring their importance in better understanding the genomic mechanisms underlying adaptation.

SHORT AND CROOKED AWN, encoding the epigenetic regulator EMF1, promotes barley awn development

The awn is a bristle-like extension from the tip of the lemma in grasses. In barley, the predominant cultivars possess long awns that contribute to grain yield and quality through photosynthesis. In addition, various awn morphological mutants are available in barley, rendering it a useful cereal crop to investigate the mechanims of awn development. Here, we identified the gene causative of the short and crooked awn (sca) mutant, which exhibits a short and curved awn phenotype. Intercrossing experiments revealed that the sca mutant induced in the Japanese cultivar (cv.) "Akashinriki" is allelic to the independently isolated moderately short-awn mutant breviaristatum-a (ari-a). Map-based cloning and sequencing revealed that SCA encodes the Polycomb group-associated protein EMBRYONIC FLOWER 1. We found that SCA affects awn development through the promotion of cell proliferation, elongation, and cell wall synthesis. RNA sequencing of cv. Bowman backcross-derived near-isogenic lines of sca and ari-a6 alleles showed that SCA is directly or indirectly involved in promoting the expression of genes related to awn development. Additionally, SCA represses various transcription factors essential for floral organ development and plant architecture, such as MADS-box and Knotted1-like homeobox genes. Notably, the repression of the C-class MADS-box gene HvMADS58 by SCA in awns is associated with the accumulation of the repressive histone modification H3K27me3. These findings highlight the potential role of SCA-mediated gene regulation, including histone modification, as a novel pathway in barley awn development.

Host-pathogen protein interaction studies: quality control of cDNA libraries using nanopore sequencing

Protein-protein interactions (PPI) play a key role in host-pathogens interaction studies, as proteins are essential to many cellular mechanisms. The yeast two-hybrid (Y2H) approach is a well-established method for high-throughput PPI screening and mapping of protein interaction networks. The success of this approach partially depends on the quality and representativeness of the host cDNA library, which can be constructed from the transcriptomic content of a selected host cellular type. However, evaluating the relevance of the cDNA library content remains challenging, and one of the key limitations of this interactomic approach is the occurrence of false-negative results (i.e., the absence of detectable interactions). Here, we report a direct, long read, high-throughput sequencing method using Oxford Nanopore Technologies, to assess the completeness of the host cDNA library used in host-pathogen interactions Y2H screening. This approach enables easy identification of possible downstream screened genes in PPI assays, minimizing sequencing biases and bioinformatics handling of the data. This study was performed on a cDNA library, generated from A549 human lung carcinoma cells. We were able to identify 12,123 protein coding genes from the sequencing of whole plasmids containing the cDNA inserts, that were further analyzed via functional pathways enrichment for deeper characterization. This diversity and relative abundance evaluation method could be a first step when generating new cDNA libraries of interest for PPI studies, ensuring the validity and suitability of the host library before proceeding with all Y2H screening steps.

A multi-tissue atlas of allelic-specific expression reveals the characteristics, mechanisms, and relationship with dominant effects in cattle

BACKGROUND

Allele-specific expression (ASE) analysis is a crucial tool for validating expression quantitative trait loci (eQTLs), identifying causal variants associated with complex traits, and investigating the genetic mechanisms underlying heterosis. In this study, we characterized ASE variants across 35 tissues using 7532 publicly available RNA-seq datasets. Additionally, we explored the mechanisms driving ASE through integration with epigenomic data and examined the relationship between ASE and dominance effects on gene expression and milk-related traits in Holstein cattle.

RESULTS

ASE variants exhibited stronger tissue specificity and lower reproducibility compared to eQTLs. Interestingly, variants with opposite directional effects demonstrated greater resilience across diverse environments. Functional annotation revealed that ASE variants were enriched in both enhancer and promoter regions during transcription and implicated in post-transcriptional and translational processes, including mutations that affect mRNA splicing and trigger nonsense-mediated decay. Analysis of eQTLs, splicing QTLs (sQTLs), and validated QTLs associated with milk-related traits in Holstein cattle, coupled with enrichment analysis in QTL databases and effect size evaluation, indicated that ASE variants were more closely aligned with dominant effects than additive effects, particularly in reproductive and immune-related tissues/traits, which exhibited higher levels of heterosis.

CONCLUSIONS

Our findings not only enhance our understanding of the genetic mechanisms underlying heterosis and ASE formation but also provide a valuable resource of regulatory variants that can be leveraged to improve economic traits through molecular breeding or the strategic exploitation of heterosis.

Haplotype resolved chromosome-level genome assembly of the gold barb (Barbodes semifasciolatus)

The gold barb (Barbodes semifasciolatus), a member of the Cyprinidae family, exhibits remarkable adaptability to highly acidic environments, making it an ideal model for studying extreme environmental adaptation. However, its genome has not been previously characterized. To address this, we assembled a high-quality chromosome-scale genome for B. semifasciolatus using High-Fidelity (HiFi) sequencing and Hi-C technology. The resulting haplotype-resolved assemblies, spanning 776 Mb and 779 Mb across 25 chromosomes, achieved genome coverages of 99.5% and 99.7%, respectively, and included four gap-free chromosomes. Genome quality assessment using BUSCO indicated a high completeness score of 98.2% for haplotype1 and 98.3% for haplotype2, further validated by strong synteny with the zebrafish (Danio rerio), confirming the assembly's integrity and continuity. Through integration of full-length transcriptome data, RNA sequencing, and homology-based annotation, we identified 26,057 protein-coding genes with 2,087 pseudogenes in haplotype 2, and 25,622 protein-coding genes with 2,101 pseudogenes in haplotype 1. This high-resolution genome assembly is a crucial resource for advancing research in the Cyprinidae, particularly for understanding adaptive evolution in extreme environments.

Characteristics of SARS-CoV-2 variants and potential co-infected pathogens in hospitalized patients based on metagenomic next-generation sequencing

Metagenomic next-generation sequencing (mNGS) is widely used to diagnose complex infections in hospitalized patients, particularly those associated with COVID-19 which has garnered significant concern over the past five years. To investigate the molecular epidemic of the viral variant and the potential co-infection pathogens, we conducted retrospective mNGS analysis of 254 SARS-CoV-2-positive specimens collected from 200 hospitalized patients between March and September 2023. Phylogenetic analysis of the identified Omicron subvariants showed minimal evolutionary divergence, with no association between sub-lineages and pneumonia severity. Notably, mNGS demonstrated enhanced detection of polymicrobial coinfections, identifying bacterial, fungal, and viral co-pathogens in 92.5% (185/200) of cases. Pneumonia severity was associated with advanced age (proportion of elderly patients: 61.1 vs 78.3%; p = 0.032) and comorbid conditions, particularly diabetes mellitus (OR 2.03, 95% CI 1.03-4.02, p = 0.041), but showed no correlation with SARS-CoV-2 sub-lineages or coinfecting pathogens. While mNGS enhances coinfection diagnosis, COVID-19 outcomes are predominantly driven by host factors rather than Omicron subvariant evolution. Prioritized monitoring of elderly and comorbid individuals remained critical for severe pneumonia management.

Chromosomal-level genome assembly of solitary bee pollinator Osmia excavata Alfken (Hymenoptera: Megachilidae)

Osmia spp. is a genus of solitary bees that serves as excellent pollinators for various fruit trees and has the potential to enhance pollination services in both agricultural and natural ecosystems. However, the absence of high-quality genomic resources limits our insights into evolutionary biology and ecological adaptations of Osmia. Here, we present a chromosome-level genome of Osmia excavata, using PacBio, Illumina, and Hi-C data. The genome has a total size of 164.35 Mb, with a scaffold N50 of 9.81 Mb, and the majority of contigs (98.50%, 161.88 Mb) are organized into sixteen chromosomes. BUSCO analysis reveals a completeness score of 99.7% (n = 1,367), with 99.6% identified as single-copy BUSCOs and 0.1% as duplicated BUSCOs. The genome contains 13.46% (22.11 Mb) repetitive elements and encodes 11,452 predicted protein-coding genes. This study provides a crucial genomic resource for our understanding of solitary bees' evolution and ecological roles.

Pangenome analysis reveals yield- and fiber-related diversity and interspecific gene flow in Gossypium barbadense L

Gossypium barbadense is renowned for its superior fiber quality, particularly its extra-long fibers, although its fiber yield is lower compared to G. hirsutum. Here, to further reveal fiber-related genomic variants of G. barbadense, we de novo assemble 12 genomes of G. barbadense that span the wild-to-domesticated continuum, and construct a graph-based pangenome by integrating these assemblies and 17 publicly available tetraploid cotton genome assemblies. We uncover the divergent evolutionary trajectories and subsequent exchanges between G. barbadense and G. hirsutum through investigation of structural variants (SVs). We perform the SV-based GWAS analysis in G. barbadense and identify four, three, and seven candidate SVs for fiber length, fiber strength, and lint percentage, respectively. Furthermore, we detect the underlying candidate genes and uncover the origin and distribution of favorable alleles, and reveal the tradeoff between lint percentage and fiber quality. These pangenome and trait-associated SVs provide insights into and resources for improving cotton fiber.

Computational and biological modeling of IGF1R inhibition for multifocal medulloblastoma

BACKGROUND

Leptomeningeal metastasis in medulloblastoma poses challenges for effective treatments due to the blood-brain barrier (BBB), which may be addressed through intrathecal or intraventricular drug delivery. However, the lack of pharmacokinetic modeling for pathological cerebrospinal fluid (CSF) geometries has limited the ability to predict effective intrathecal and intraventricular drug exposure.

METHODS

A patient-specific computational fluid dynamics "in silico" trial was conducted to simulate CSF movement to examine the tumor microenvironment in terms of drug-target exposure over time following intraventricular delivery via Omaya Reservoir. Simultaneously, we conducted cellular adhesion experiments to test the therapeutic potential of IGF1R inhibition on metastasis under patient-specific flow conditions generated by computational analysis.

RESULTS

A 3-dimensional computational fluid dynamics (CFD) model based on patient-specific conditions was obtained to predict an efficacious drug concentration, providing guidance for therapeutic drug exposure at targeted sites. Microfluidic experiments for IGF1R inhibition of cellular adhesion showed the potential for reduced attachment of medulloblastoma to leptomeningeal cells to prevent metastasis.

CONCLUSIONS

This study offers insights from patient-specific in silico trials for the precision delivery of small-molecule drugs for the treatment of central nervous system (CNS) malignancies.

A high-quality genome assembly of Annona squamosa (custard apple) provides functional insights into an emerging fruit crop

Annona squamosa, also known as custard apple, is an emerging fruit crop with medicinal significance. We constructed a high-quality genome of A. squamosa along with transcriptome data to gain insights into its phylogeny, evolution, and demographic history. The genome has a size of 730.4 Mb with an N50 value of 93.2 Mb assembled into seven pseudochromosomes. The demographic history showed a continuous decline in the effective population size of A. squamosa. Phylogenetic analysis revealed that magnoliids were sister to eudicots. Genome syntenic and Ks distribution analyses confirmed the absence of a recent whole-genome duplication event in the A. squamosa. Gene families related to photosynthesis, oxidative phosphorylation, and plant thermogenesis were found to be highly expanded in the genome. Comparative analysis with other magnoliids revealed the adaptive evolution in the genes of flavonoid biosynthesis pathway, amino sugar, nucleotide sugar and sucrose metabolism, conferring medicinal value, and enhanced hexose sugar accumulation. In addition, we performed genome-wide identification of SWEET genes. Our high-quality genome and evolutionary insights of this emerging fruit crop, thus, serve as a valuable resource for advancing studies in functional genomics, evolutionary biology, and crop improvement.

Revisiting the emergence of the Chikungunya virus in Alagoas, Northeast of Brazil

Chikungunya virus (CHIKV), an Alphavirus, emerged in the Americas in 2013 and was first documented in Brazil in September 2014, in the states of Pará and Bahia. Although Alagoas state officially reported its first case in late 2015, this study investigated potential earlier unreported cases by analyzing samples from a 2013-2014 Orthoflavivirus serological survey. We screened sera from patients with acute febrile illness, initially suspected of dengue but negative in molecular tests for the genus Orthoflavivirus, using ELISA (IgM/IgG), viral isolation, PCR, and next-generation sequencing. Two samples collected in June and August 2014 tested positive for anti-CHIKV IgM, and four additional samples collected between June and September 2014 tested positive for anti-CHIKV IgG antibodies. From one sample IgM-positive (630H) collected in August 2014, we isolated and sequenced a nearly complete genome (95.53% coverage, 2714× depth) classified as the East-Central-South-African (ECSA) genotype. Phylogenetic analyses revealed that the Alagoas-2014 genome formed a distinct, well-supported clade separate from the Bahia 2014 lineage. Temporal inference dated this lineage's origin to October 2013 (90% CI: April 2013-March 2014), suggesting a new introduction of ECSA into Alagoas. This genomic evidence, along with serological data, confirms the undetected early circulation of CHIKV in Alagoas and suggests a possible introduction of ECSA in Brazil in 2014, distinct from the well-documented introduction in Bahia.

Loss of phytochromobilin synthase activity leads to larger seeds with higher protein content in soybean

Seed weight is an important agronomic trait that is related to seed size and determines yield in soybean (Glycine max). We previously identified a spontaneous soybean mutant with light green leaves called ygl2. Here, we cloned YGL2, which encodes a phytochromobilin (PΦB) synthase involved in synthesizing the chromophore of the photoreceptor phytochrome. The lesion in ygl2 is a 10-bp deletion, causing a frameshift mutation and a premature stop codon that truncates the encoded protein. In contrast to the wild type, ygl2 lacks PΦB synthase activity and function. This appears to promote cell expansion, thus increasing seed weight. Surprisingly, the ygl2 mutant also exhibits excellent traits including early maturity and high protein content. Moreover, under the condition of dense planting (3 cm), the yield of YGL2 mutant was significantly increased. Mutants harboring ygl2 mutations that we generated via gene editing had enlarged seeds with high protein content. Moreover, the expression levels of the photoperiod sensitive genes (E1, FT2a, FT5a) were lower in the ygl2 mutant than in the wild type. Mutating the YGL2 gene resulted in increased biliverdin content and decreased heme content. We determined that Lhcb4, a chlorophyll a/b binding protein in photosystem II, interacts with YGL2 but not with the mutant version of the protein. We thus identified a mutation in a PΦB synthase gene that enhances seed weight in soybean, providing a promising breeding target for this important crop.

Rapid reprogramming and stabilization of homoeolog expression bias in hexaploid wheat biparental populations

BACKGROUND

Differences in the relative level of expression of homoeologs, known as homoeolog expression bias, are widely observed in allopolyploids. While the evolution of homoeolog expression bias through hybridization has been characterized, on shorter timescales such as those found in crop breeding programs, the extent to which homoeolog expression bias is preserved or altered between generations remains elusive.

RESULTS

Here we use biparental mapping populations of hexaploid wheat (Triticum aestivum) with a common "Paragon" parent to explore the inheritance of homoeolog expression bias in the F5 generation. We found that homoeolog expression bias is inherited for 26-27% of triads in both populations. Most triads conserved a similar homoeolog expression bias pattern as one or both parents. Inherited patterns were largely driven by changes in the expression of one homoeolog, allowing homoeolog expression bias in subsequent generations to match parental expression. Novel patterns of homoeolog expression bias occurred more frequently in the biparental population from a landrace × elite cross, than in the population with two elite parents.

CONCLUSIONS

These results demonstrate that there is significant reprogramming and stabilization of homoeolog expression bias within a small number of generations that differs significantly based on the parental lines used in the crossing.