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Wu, J.

Publications and source records attributed to Wu, J..

At least 235 records · Page 13Linked to original sources

Reshaping epistatic network modules enhances wheat yield potential

Increasing wheat yield is a key approach to ensuring global food security and an enduring focus in crop breeding. Here, we assembled a panel of 3,030 wheat lines to dissect the genetic mechanisms of yield improvement. We conducted large-scale field trials across five ecological environments over two consecutive years to evaluate yield performance and constructed a haplotype atlas using the Wheat 660K genotype array. 234 quantitative trait loci (QTLs) and 522 haplotype blocks (HBs) were identified for 14 traits through genome-wide association studies (GWAS), including 10 QTLs and 35 HBs associated with grain yield. Genomic analysis revealed that wheat yield improvement is primarily driven by changes in the epistatic network rather than the introduction of new haplotype segments. SNPs or HBs explain 53.3%-62.9% of the phenotypic variation in yield, whereas epistasis explains 70.4%, highlighting the role of epistasis in yield improvement. Moreover, yield improvement is significantly correlated with the accumulation of favorable epistatic modules. Pedigree-based analysis revealed that the modules remained relatively stable under the pressure of breeding selection, while new favorable modules were also created during hybrid breeding, highlighting that crop design breeding should be based on genetic modules. This study provides insights into genetic mechanism of wheat yield improvement and guidance for designing future wheat in the era of artificial intelligence.

genetics↗

The sialylation pattern of dietary glycopeptides is vital for inhibiting pathogens and modulating gut microbiota in elderly individuals

N-glycosylation is a post-translational modification of proteins that can influence the structure and function of glycoproteins. Edible birds nest (EBN) contains highly sialylated mucins with N-glycans and O-glycans, while casein glycomacropeptide (CGMP) is modified with only O-glycans. We prepare EBN sialoglycopeptides through sequential protease treatment and their inhibitory effects on pathogens, including Candida albicans, Helicobacter pylori, and avian influenza virus (AIV), as well as their modulation of gut microbiota in elderly individuals, were compared with CGMP. N-glycan analysis revealed the presence of multiantenna N-glycans, characterized by sialylation and bisecting GlcNAc in the EBN glycopeptides. EBN glycopeptides significantly inhibited C. albicans and H. pylori. However, the removal of terminal sialic acid from EBN glycopeptides resulted in a marked reduction of this inhibitory effect. Using Maackia Amurensis Lectin II as an AIV mimic, EBN glycopeptides effectively inhibited AIV adhesion to MDCK cells. In vitro fecal fermentation using fecal samples from elderly individuals revealed that the EBN glycopeptide group exhibited remarkable probiotic effects on the gut microbiota, increasing the relative abundance of beneficial bacteria such as Lactobacillus and Roseibacterium, while decreasing the relative abundance of harmful bacteria such as Escherichia-Shigella and Klebsiella. Overall, EBN glycopeptide, rich in sialylated N-glycans and O-glycans, strongly inhibited pathogenic microorganisms and showed superior probiotic properties compared to CGMP with sole O-glycosylation.

biochemistry↗

The multiomics landscape of small peptides encoded by long non-coding RNA-derived sORFs in rice

Long non-coding RNAs (lncRNAs), representing the non-coding RNA regions, constitute a significant portion of the genomes in complex organisms. Recent studies suggest that some lncRNAs have the capability to encode peptides. However, the presence of the lncRNA-derived sORFs-encoded polypeotides (LSEPs) in plants is not well understood. In this study, we developed a multi-omics approach that encompasses transcriptomics, translatomics (Ribo-seq), and proteomics to identify of LSEPs in rice. Among the 2764 identified lncRNAs, 42.69% were found to be bound by the ribosome, indicating a potential for encoding. Optimized small peptide extraction protocol was further developed, and the small peptides from rice leaves were extracted and subjected to LC-MS/MS analysis, leading to the identification of a total of 403 LSEPs across four constructed search databases. This work confirms the peptide-coding ability of lncRNAs in plants. Collectively, our study establishes an efficient multi-omics method for identifiying small peptides encoded by lncRNAs, which may be valuable for large-scare screening of LSEPs in plants.

plant biology↗

Coordinated horizontal transfer of multiple genes assembles a carotenoid biosynthesis pathway in aphids

Horizontal gene transfer (HGT) plays a crucial role in genome evolution, especially when it enables the acquisition and assembly of multi-step biosynthetic pathways. Here, we investigate the evolutionary origins of carotenoid biosynthesis genes in aphids to determine whether multiple functionally related genes were acquired through HGT. We analyzed carotenoid biosynthesis genes in 23 aphid genomes based on homologs in plants, fungi, and bacteria. Phylogenetic analyses revealed that Geranylgeranyl pyrophosphate synthase (GPS), Phytoene synthase (PS), and Carotenoid desaturase (CD) were acquired via HGT from fungi by ancestral insect species, while Carotenoid cleavage oxygenase (CCO) appears to be a native insect gene. Most insect genomes contain two GPS copies, likely resulting from independent HGT events, whereas aphid genomes exhibit extensive duplication of PS and CD, a pattern uncommon in other insects. Expression analyses across aphid species with distinct pigmentation showed that these genes are broadly transcribed with substantial variability in expression levels. In Myzus persicae, comparative expression analysis between reddish and greenish clones, as well as a green-reddish clone with green and red color polymorphism, revealed that PS-4390 is a novel contributor to red pigmentation in M. persicae, in addition to CD-4400, a homolog of the tor gene in Acyrthosiphon pisum. These findings provide strong evidence that HGT can introduce multiple functionally related genes into recipient genomes, allowing them to be co-opted into a functional biosynthetic pathway.

evolutionary biology↗

Discovery of a VHL molecular glue degrader of GEMIN3 by Picowell RNA-seq

Targeted protein degradation (TPD) is an emerging therapeutic modality in which small molecules are used to recruit targets to the natural protein degradation machinery of the cell. Molecular glue degraders (MGD) are monovalent small molecules that accomplish this by redirecting E3 ubiquitin ligases to target proteins, offering the potential to degrade previously unliganded and "undruggable" proteins in cancer, neurodegenerative, and other diseases. While attractive due to their drug-like properties, MGDs are exceptionally hard to discover and have largely been identified serendipitously. The Von Hippel-Lindau (VHL) E3 ligase is the second most widely used effector for TPD, though current VHL-based degraders are primarily large heterobifunctional PROTACs (proteolysis-targeting chimeras) designed using target-based ligands. Here, we have instead pursued target-agnostic discovery of VHL MGDs leveraging proprietary ultra-miniaturized microfluidics devices (Picowells) to facilitate unbiased RNA-seq screening of a biased E3-focused library. This resulted in dGEM3, a novel VHL molecular glue that targets the survival of motor neuron (SMN) complex member GEMIN3 for degradation. Through a combination of cellular, biochemical, and biophysical assays, we have characterized the GEMIN3 degron within its helicase ATP-binding domain, and how the kinetics of ternary complex formation impact degradation. These findings provide insights on the re-programmability of VHL for novel targets using drug-like molecular glues.

biochemistry↗

Hi-C for genome-wide detection of enhancer-hijacking rearrangements in routine lymphoid cancer biopsies

Standard techniques for detecting genomic rearrangements in formalin-fixed paraffin-embedded (FFPE) biopsies have important limitations. We performed FFPE-compatible Hi-C on 44 clinical biopsies comprising large B-cell lymphomas (n=18), plasma cell neoplasms (n=14), and other diverse lymphoid cancers, identifying consistent topological differences between malignant B cell and plasma cell states. Hi-C detected expected oncogene rearrangements at high concordance with fluorescence in-situ hybridization (FISH) and supported enhancer-hijacking in recurrent rearrangements of BCL2, CCND1, and MYC, plus unanticipated variants involving homologous loci. Hi-C identified unanticipated non-coding rearrangements involving PD-1 ligand genes and other loci of potential therapeutic relevance, distinguished between functionally divergent classes of BCL6 rearrangements, and provided topological information supporting the interpretation of atypical MYC rearrangements. In biopsies lacking MYC-activating rearrangements, Hi-C revealed differential interactions with functionally-validated disease-specific native MYC locus enhancers. FFPE-compatible Hi-C detects oncogene rearrangements and their topological consequences at genome-wide scale, finding clinically-relevant drivers that are missed by standard approaches.

genomics↗

Pangenome analyses of tea plant reveal structural variations driven gene expression alterations and agronomic trait diversification

Tea plants, one of the worlds most economically significant beverage crops, exhibit extensive genetic diversity and a rich array of secondary metabolites. While structural variations (SVs) are key drivers of phenotypic innovation, their regulatory roles in transcriptional networks and agronomic trait diversification remain underexplored in this perennial crop. We constructed a pangenome from 21 representative tea accessions and their wild relatives. Comparative analysis revealed that wild relatives harbor a greater abundance of gibberellin-related genes, whereas cultivated accessions exhibit an expansion of defense-related genes. We identified 522,428 non-redundant SVs, primarily insertions/deletions (73.56%), which were enriched in promoter regions. These SVs influenced the expression of genes governing flavor compounds, including those involved in flavonoid, amino acid, and terpenoid biosynthesis. Population SV analysis of 275 tea accessions uncovered three haplotypes in the ANS3 gene promoter region, with Hap1, containing a 192 bp insertion, predominantly found in wild relatives but largely lost in modern cultivars. This insertion enhanced CtANS3 expression, increasing anthocyanin accumulation. Additionally, a 159 bp insertion in the CtLRR1 promoter reduced resistance to Colletotrichum gloeosporioides in wild relatives. Our findings underscore SVs as pivotal regulators of genomic diversity, flavor differentiation, and adaptive evolution in tea plant domestication.

genomics↗

Homoharringtonine Promotes FTO Degradation to Suppress LILRB4-Mediated Immune Evasion in Acute Monocytic Leukemia

Acute monocytic leukemia (AML-M5), a subtype of acute myeloid leukemia, is a highly aggressive malignancy characterized by a poor prognosis, primarily due to the ability of leukemic cells to evade immune surveillance. In this study, we demonstrate that homoharringtonine (HHT), an FDA-approved therapeutic agent for chronic myeloid leukemia (CML), inhibits this immune evasion by targeting the FTO/m6A/LILRB4 signaling pathway in monocytic AML. Utilizing RNA sequencing (RNA-seq) and various functional assays, we reveal that HHT treatment significantly reduces LILRB4 expression at both the RNA and protein levels, suggesting that the effects of HHT on LILRB4 are distinct from its well-established role as a protein synthesis inhibitor. Mechanistically, HHT treatment markedly increases global levels of RNA m6A in THP-1 cells by promoting the degradation of FTO, which subsequently diminishes the expression of its downstream targets, MLL1 and LILRB4. Furthermore, in vitro and in vivo analyses employing monocytic AML cell lines, mouse-derived AML xenograft models, and patient samples collectively support the conclusion that HHT suppresses immune evasion in monocytic AML by reducing LILRB4 expression. Importantly, the downregulation of LILRB4 resulting from HHT treatment enhances the susceptibility of THP-1 cells to CD8+ T cell cytotoxicity, accompanied by increased markers of immune activation. Overall, our findings position HHT as a promising clinical agent for enhancing CD8+ T cell-based cancer immunotherapy by mitigating immune evasion in monocytic AML. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=147 HEIGHT=200 SRC="FIGDIR/small/643466v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@e72e5dorg.highwire.dtl.DTLVardef@19519aeorg.highwire.dtl.DTLVardef@1c8f786org.highwire.dtl.DTLVardef@f2a963_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Rewiring of 3D chromatin topology orchestrates transcriptional reprogramming in muscle fiber-type specification and transformation

The composition of muscle fibers, characterized by distinct contractile and metabolic properties, significantly influences meat quality and glucose homeostasis. However, the mechanisms by which three-dimensional (3D) genome topology integrates with epigenetic states to regulate muscle fiber specification and transformation remain poorly understood. Here, we present an integrative analysis of the transcriptome, epigenome, and 3D genome architecture in the slow-twitch glycolytic extensor digitorum longus (EDL) and fast-twitch oxidative soleus (SOL) muscles. Global remodeling of enhancer-promoter (E-P) interactions emerged as a central driver of transcriptional reprogramming associated with muscle contraction and glucose metabolism. We identified tissue-specific super-enhancers (SEs) that regulate muscle fiber-type specification through cooperation of chromatin looping and transcription factors such as KLF5. Notably, the SE-driven activation of STARD7 facilitated the transformation of glycolytic fibers into oxidative fibers by mitigating reactive oxygen species levels and suppressing ERK MAPK signaling. This study elucidates the principles of 3D genome organization in the epigenetic regulation of muscle fiber specification and transformation, providing a foundation for novel therapeutic strategies targeting metabolic disorders and enhancing meat quality. O_FIG O_LINKSMALLFIG WIDTH=142 HEIGHT=200 SRC="FIGDIR/small/643571v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@990eecorg.highwire.dtl.DTLVardef@a2b491org.highwire.dtl.DTLVardef@1fcd142org.highwire.dtl.DTLVardef@10e4d47_HPS_FORMAT_FIGEXP M_FIG Schematic overview of the study. C_FIG

developmental biology↗

TSHR-targeting nucleic acid aptamer treats Graves' ophthalmopathy via novel allosteric inhibition

Abnormal thyrotropin receptor (TSHR) signaling drives a spectrum of diseases affecting hundreds of millions globally, including Graves disease (GD), Graves ophthalmopathy (GO), hyperthyroidism, and thyroid cancers. Therefore, TSHR is considered an attractive therapeutic target with immense drug discovery potential. Currently, there are no clinically available TSHR inhibitors. To address this unmet medical need, we developed YC3, a functional nucleic acid aptamer targeting TSHR, via an innovative approach combining protein-targeting cell-SELEX and functional selection. YC3 exhibited nanomolar affinity with potent TSHR inhibition. Its therapeutic potential was comprehensively evaluated both in vitro and in vivo for GO. In GO patient-derived orbital fibroblasts (OFs), YC3 reversed thyroid-stimulating antibodies (TSAbs)-induced cell activation, suppressing inflammatory cytokines and extracellular matrix (ECM) secretion. In a GO mouse model, YC3 treatment markedly attenuated orbital inflammation, ECM deposition, and fibrosis, ameliorating the pathological remodeling of orbital tissue. Mechanistically, YC3 bound to a previously unidentified allosteric site within the leucine-rich repeat domain of TSHR, thereby inhibiting receptor activation. This study identifies YC3 as a promising TSHR-targeted therapy and unveils a new druggable site for inhibitor design. It also provides the first preclinical evidence supporting pharmacological TSHR inhibition for GO treatment, advancing therapeutic development for TSHR-related diseases.

biochemistry↗

UHRF1 is critical for tumor-promoting inflammation and tumorigenesis in retinoblastoma

Retinoblastoma, the most common pediatric intraocular malignancy, arises from RB1 inactivation, leading to uncontrolled proliferation of retinal progenitor cells. Epigenetic dysregulation a key driver of retinoblastoma progression, yet the underlying mechanisms are poorly understood. UHRF1, a regulator of DNA methylation and chromatin remodeling, has been implicated in oncogenesis but its role in retinoblastoma has not been fully characterized. To investigate Uhrf1s role in tumor initiation and progression, we generated a genetically engineered mouse model of retinoblastoma with conditional Uhrf1 knockout. Remarkably, Uhrf1 loss completely blocked tumor formation, despite persistent early oncogenic events. Transcriptomic and epigenomic profiling revealed that Uhrf1 is essential for tumor progression, facilitating oncogenic transcription, chromatin accessibility, and aberrant DNA methylation. Beyond its epigenetic role, we found Uhrf1 modulates the tumor immune microenvironment, promoting chemokine secretion and microglial infiltration, suggesting that Uhrf1 promotes immune cell recruitment. Mechanistically, Uhrf1 enhances chemokine expression through NF-{kappa}B signaling, establishing a novel connection between epigenetic regulation and tumor-associated immune responses. These findings establish Uhrf1 as a critical driver of retinoblastoma progression, essential for tumor maintenance but not initiation. By sustaining oncogenic transcriptional programs and shaping a pro-tumor immune microenvironment, Uhrf1 emerges as a promising therapeutic target for inhibiting tumor growth and immune evasion.

cancer biology↗

Climate change and the thermal performance of a high protein food source: Wolffia globosa

Wolffia globosa is a tropical duckweed native to Southeast Asia, where it is harvested for food. This aquatic plant has a fast growth rate, a high protein content, and is also a source of important nutrients. Therefore, it could play an important role in food security under climate change and population growth. We provide the first thermal performance curve for W. globosa, and use this data to understand how climate change impacts on temperature in Southeast Asia may affect production. We find that the maximum relative growth rate occurs at constant temperatures of [~]32C. We find no significant difference between growth at current mean conditions and temperatures predicted in the next 40 years according to the high emissions scenario (SSP5-8.5 scenario) in Thailand, Laos and Myanmar when temperatures are held constant. However, the thermal performance curve is best described as asymmetric, with growth rates that fall rapidly at temperatures above this optimum. As a result, when temperatures are allowed to fluctuate about the mean in a pattern similar to recent heatwave conditions in Thailand, we find significantly lower growth rates at the optimum than at current mean temperatures. This decrease is driven by a significant increase in frond death at higher temperatures. However, given the fast growth rate of this species relative to other food crops, and the mitigating impact of water on the magnitude of temperature fluctuations, it seems likely that W. globosa may more rapidly recover from extreme heat events than other crop species. Therefore, it is likely to be a suitable candidate for adapting to climate change impacts.

plant biology↗

Restoration of excitation/inhibition balance enhances neuronal signal-to-noise ratio and rescues social deficits in autism-associated Scn2a-deficiency

Social behavior is critical for survival and adaptation, which is profoundly disrupted in autism spectrum disorders (ASD). Social withdrawal due to information overload was often described in ASD, and it was suspected that increased basal noise, i.e., excessive background neuronal activities in the brain could be a disease mechanism. However, experimental test of this hypothesis is limited. Loss-of-function mutations (deficiency) in SCN2A, which encodes the voltage-gated sodium channel NaV1.2, have been revealed as a leading monogenic cause of profound ASD. Here, we revealed that Scn2a deficiency results in robust and multifaceted social impairments in mice. Scn2a-deficient neurons displayed an increased excitation-inhibition (E/I) ratio, contributing to elevated basal neuronal noise and diminished signal-to-noise ratio (SNR) during social interactions. Notably, the restoration of Scn2a expression in adulthood is able to rescue both SNR and social deficits. By balancing the E/I ratio and reducing basal neuronal firing, an FDA-approved GABAA receptor-positive allosteric modulator improves sociability in Scn2a-deficient mice and normalizes neuronal activities in translationally relevant human brain organoids carrying autism-associated SCN2A nonsense mutation. Collectively, our findings revealed a critical role of the NaV1.2 channel in the regulation of social behaviors, and identified molecular, cellular, and circuitry mechanisms underlying SCN2A-associated disorders. HIGHLIGHTSO_LINaV1.2 deficiency leads to pronounced social deficits in mice. C_LIO_LINaV1.2 deficiency results in an overall enhanced E/I ratio, elevated basal neuronal activity, and impaired signal-to-noise ratio. C_LIO_LIBoth the enhanced E/I ratio and impaired sociability are reversible through the restoration of NaV1.2 expression in adulthood. C_LIO_LITargeted restoration of NaV1.2 in striatum-projecting neurons rescues social impairments. C_LIO_LIGABA transmission is reduced in both mouse and human organoid models of SCN2A deficiency, and acute systemic administration of GABAA receptor-positive allosteric modulators restores sociability. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=193 HEIGHT=200 SRC="FIGDIR/small/641498v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@154a323org.highwire.dtl.DTLVardef@1a27fbaorg.highwire.dtl.DTLVardef@16fa3beorg.highwire.dtl.DTLVardef@6712c2_HPS_FORMAT_FIGEXP M_FIG C_FIG Graphical abstract: Severe Scn2a deficiency leads to a predominate decrease in GABA transmission with an overall enhanced E/I ratio, elevated basal neuronal activity, impaired SNR, and social deficits in adult NaV1.2-deficient mice.

neuroscience↗

PRRSV evades innate immune cGAS-STING antiviral function via its Nsp5 to deter STING translocation and activation

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is an important pathogen that seriously endangers pig breeding, causing significant economic losses to the global swine industry. Our previous study found that the DNA sensing innate cGAS-STING signaling pathway plays an important role in inducing interferon (IFN) upon PRRSV infection and inhibition of PRRSV replication. However, the immune evasion and its mechanism by PRRSV is still unclear. In current study, we found that PRRSV Non-structural protein 5 (Nsp5) strongly inhibits the cGAS-STING-IFN antiviral response. Further, we found that Nsp5 interacts with STING, blocking STING transport from ER to Golgi apparatus and interfering with STING recruitment of TBK1/IKK{varepsilon}/IRF3. Finally, we demonstrated that the Nsp5 36-47 and 58-67 amino acid regions are critical regions for inhibiting STING activity and PRRSV replication. The study describes a novel mechanism by PRRSV for suppression of the host innate antiviral response and have implications for our understanding of PRRSV pathogenesis. Author summaryThe innate immune system is the first line of host defense against infections. PRRSV is an immunosuppressive pathogen that has developed different strategies to evade the host innate immune responses. Here, we demonstrate for the first time that PRRSV utilizes its non-structural protein Nsp5 to inhibit the innate immune cGAS-STING-IFN signaling pathway, promoting the viral replication. Nsp5 can inhibit the cGAS-STING pathway by interacting with STING, blocking STING transport from ER to Golgi apparatus and interfering with STING recruitment of TBK1/IKK{varepsilon}/IRF3. In particular, the 36-47 and 58-67 amino acid regions of the Nsp5 is indispensable. This information will help us understand PRRSV-host interactions and provides new insights into the prevention and control of PRRSV.

immunology↗

RNA Transcripts Serve as a Template for Double-Strand Break Repair in Human Cells

Double-strand breaks (DSBs) are toxic lesions that lead to genome instability. While canonical DSB repair pathways typically operate independently of RNA, emerging evidence suggests that RNA:DNA hybrids and transcripts near damaged sites can influence repair outcomes. However, a direct role for transcript RNA as a template during DSB repair in human cells is yet to be established. In this study, we designed fluorescent- and sequencing-based assays, which demonstrated that RNA-containing oligonucleotides and messenger RNA serve as templates to promote DSB repair. We conducted a CRISPR/Cas9-based genetic screen to identify factors that promote RNA-templated DSB repair (RT-DSBR), and of the candidate polymerases, we identified DNA polymerase-zeta (Pol{zeta}) as the potential reverse transcriptase that facilitates RT-DSBR. Furthermore, by analyzing sequencing data from cancer genomes, we identified the presence of whole intron deletions, a unique genomic scar reflective of RT-DSBR activity generated when spliced mRNA serves as the repair template. These findings highlight RT-DSBR as an alternative pathway for repairing DSBs in transcribed genes, with potential mutagenic consequences.

molecular biology↗

Intersecting impact of CAG repeat and Huntingtin knockout in stem cell-derived cortical neurons

Huntingtons Disease (HD) is caused by a CAG repeat expansion in the gene encoding Huntingtin (HTT). While normal HTT function appears impacted by the mutation, the specific pathways unique to CAG repeat expansion versus loss of normal function are unclear. To understand the impact of the CAG repeat expansion, we evaluated biological signatures of HTT knockout (HTT KO) versus those that occur from the CAG repeat expansion by applying multi-omics, live cell imaging, survival analysis and a novel feature-based pipeline to study cortical neurons (eCNs) derived from an isogenic human embryonic stem cell series (RUES2). HTT KO and the CAG repeat expansion influence developmental trajectories of eCNs, with opposing effects on the growth. Network analyses of differentially expressed genes and proteins associated with enriched epigenetic motifs identified subnetworks common to CAG repeat expansion and HTT KO that include neuronal differentiation, cell cycle regulation, and mechanisms related to transcriptional repression and may represent gain-of-function mechanisms that cannot be explained by HTT loss of function alone. A combination of dominant and loss-of-function mechanisms are likely involved in the aberrant neurodevelopmental and neurodegenerative features of HD that can help inform therapeutic strategies.

cell biology↗

Population-scale gene expression analysis reveals the contribution of expression diversity to the modern wheat improvement

Changes in gene expression are crucial for crop breeding, yet population genomics has primarily focused on sequence polymorphisms rather than gene expression diversity. The strategy of using single genome reference for RNA-seq analysis could not handle introgression bias, especially for hexaploidy wheat. Here, we conducted RNA-seq for 328 wheat lines, including representative diverse landraces and elite cultivars from China and the United States, to investigate the role of gene expression variation in shaping agronomic traits. Using pan-genome resources, we identified 20,615 more transcripts than using the Chinese Spring reference genome alone. We constructed a pan-gene atlas regulatory map through eQTL analysis, demonstrating that genes introgressed from wild relatives were under tight genetic control. Genes responding to environmental stress show higher activity after introgressed into the wheat genome, demonstrating how long-term breeding selection impacted the gene expression regulation of targeted introgression. Multi-omics modeling identified 231 high-confidence candidate genes for 34 field agronomic traits and the seedling resistance phenotypes of 8 powdery mildew isolates. More than one fifth of those candidates have no homolog in Chinese Spring reference genome. By utilizing the indexed KN9204 EMS library, 80% candidates showed significant trait difference between wild type and mutant lines. Furthermore, directional shifts in genes of which expression were changed by breeding improvement demonstrated distinct adaptations to local environments. Our study constructed a pan-gene atlas to correct the reference bias of reads mapping in RNA-seq studies and revealed the expression patterns of introgressed genes within the wheat genome and their regulatory mechanisms, which highlighted the impact of breeding selection on gene expression of the worlds most important crop.

plant biology↗

Genome-wide mapping of 5'-aldehyde terminus induced by reactive oxygen species

DNA single strand breaks (SSBs) are abundant lesions due to cell metabolism and reactive oxygen species (ROS) and can lead to replication folk collapse, double strand break formation, genome rearrangements, cell death and disease. Among numerous chemical forms of SSBs, 5'-aldehyde terminus are the most abundant generated by hydroxyl radicals and pose significant challenge for cellular repair machinery due to the lack of specific end processing process, potentially leading to more severe biological consequences than other readily repairable SSBs. Herein we developed a new strategy to locate 5'-aldehyde terminus in genomic DNA at single-nucleotide resolution. The principle involves labelling the 5'-aldehyde terminus with an aminooxy-functionalized oligonucleotide, giving rise to a biocompatible altered DNA linkage and allowing labelled sites to be amplified by polymerase chain reaction. We sequenced the 5'-aldehyde terminus distribution in genomic DNA, nuclei, and cells following activation of the Fenton reaction. The results revealed a significant preference for adenine bases in DNA lesions and provided insights into the genome-wide distribution of such DNA damage, correlating with genomic features and chromatin accessibility. This method provide a new strategy for studies aiming to understand the biological and toxicological impacts of 5'-aldehyde termini in DNA as the form species of single strand break induced by reactive oxygen species from a human genome.

genomics↗