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PubMed2026

GenOT: generative optimal transport enables spatiotemporal interpolation and generation in cross-platform spatial transcriptomics.

Spatial transcriptomics technologies have revolutionized the analysis of spatial gene expression, yet integrating spatial information and generating data across heterogeneous samples remain challenging. We present GenOT, a generative framework combining multi-scale graph self-supervised contrastive learning with optimal transport barycenter theory for efficient cross-slice and cross-platform spatiotemporal interpolation. The core innovation of GenOT lies in introducing an optimal transport barycenter-based interpolation algorithm, which mathematically models spatial distribution differences across heterogeneous samples to reconstruct spatiotemporal gene expression dynamics. Extensive evaluations demonstrate that GenOT consistently outperforms existing approaches in spatial domain identification, cross-platform interpolation, and developmental trajectory reconstruction.

Spatial Transcriptomics↗

PubMed2024

Gene expression patterns associated with PFOA exposure in Czech young men and women.

Perfluorooctanoic acid (PFOA), a member of per- and polyfluoroalkyl substances (PFASs), has been widely used in manufacturing for decades. Currently, PFOA is strictly regulated, but due to its high stability and persistence, it is detected in both environmental as well as in human matrices. To elucidate mechanisms of PFOA toxicity in humans, we determined the genome-wide transcriptomic changes of peripheral blood mononuclear cells (PBMC) responding to PFOA exposure in a sex-stratified analysis. This work employed samples from 145 female and 143 male participants of the CELSPAC: YA study to characterize PFOA-associated transcripts in a broader context using computational analysis. PFOA-associated gene expression differed significantly between men and women, as only 2 % of mapped genes were expressed in both sexes. Disease-specific enrichment analysis revealed cancer and immune-related disease terms as those most enriched in male and female populations. Patterns of enriched terms within the gene set enrichment analysis indicated three main targets of PFOA toxicity: i) lipid metabolism for women; ii) cell cycle regulation for men; and iii) immune system response for both sexes. In summary, our genome-wide transcriptomics analysis described sex-specific differences in PFOA-associated gene expression and provided evidence about biological pathways underlying PFOA toxicity in humans.

Humans↗

PubMed2026

A nucleolar stress gene signature enables quantitative scoring across multi-omics contexts.

The nucleolus is essential for ribosome biogenesis and cellular homeostasis, and its dysfunction can induce nucleolar stress, a process implicated in cancer and other diseases. However, nucleolar stress is commonly inferred from morphological changes or a limited set of functional assays, and quantitative approaches based on gene expression profiles remain lacking. Here, we integrate literature curation with multi-dataset screening to define a nucleolar stress gene signature and develop a nucleolar stress score (NuS) applicable to bulk transcriptomics, single-cell transcriptomics, proteomics, and spatial transcriptomics. Using this framework, we show in colorectal cancer models that oxaliplatin induces nucleolar stress, suppresses nascent rRNA synthesis, and activates p53 signaling, whereas these responses are attenuated in oxaliplatin-resistant cells. Combined with a ribosome biogenesis activity score (RiboSis), NuS captures related but distinct dimensions of nucleolar function and stratifies tumors into functional states associated with clinical outcomes. NuS-based analysis of perturbational transcriptomes further prioritizes compounds with putative nucleolar stress-inducing activity. Collectively, this study provides a quantitative framework for evaluating nucleolar stress and illustrates its applications in disease stratification and drug mechanism discovery.

Cell Nucleolus↗

PubMed2026

POU2F3 expression in lung squamous cell carcinoma: transcriptomic and immunohistochemical profiling with prognosis.

BACKGROUND: Lung squamous cell carcinoma (LUSC) lacks well-defined molecular targets. This study investigated the clinical and biological relevance of POU class 2 homeobox 3 (POU2F3), a tuft cell-associated transcription factor, in LUSC. METHODS: RNA sequencing data of patients with LUSC from The Cancer Genome Atlas (TCGA cohort, n = 190) was analysed and compared to a cohort of surgically resected cases analyzed via immunohistochemistry (IHC cohort, n = 137). Prognostic impact was assessed via survival analyses. Transcriptomic features, pathway enrichment, and immune profiles were evaluated via differentially expressed gene analysis, Gene Set Enrichment Analysis, and CIBERSORTx. RESULTS: High POU2F3 expression independently predicted poor overall survival in the TCGA cohort (HR = 2.06, 95% CI: 1.04-4.08, P = 0.039). In contrast, POU2F3 expression was not prognostic in the IHC cohort (P = 0.995). Morphologically, POU2F3-positive tumours were enriched for non-keratinizing and poorly differentiated subtypes. Transcriptomic analysis showed suppression of proliferation and immune-related pathways (FDR < 0.001), with suggestive enrichment of the TGF-β (FDR = 0.143) and p53 (FDR = 0.229) signaling pathways. On immune deconvolution, POU2F3-high tumours showed a nominal increase in activated dendritic cells, which did not withstand multiple testing correction. POU2F3 protein was detected in 12.4% of tumours and was significantly associated with p53 or RB1 abnormalities (single or double) (P = 0.028). CONCLUSIONS: POU2F3 marks a transcriptionally distinct, early-stage subtype of LUSC with keratinization-related features. Its prognostic relevance appears context-dependent and requires prospective validation in uniformly treated cohorts.

Humans↗

PubMed2025

Balancing LncRNA H19 and miR-675 Bioconversion as a Key Regulator of Embryonic Myogenesis Under Maternal Obesity.

BACKGROUND: Maternal obesity (MO) impairs fetal skeletal muscle development, but the underlying mechanisms remain poorly defined. The regulatory roles of lncRNA H19 and its first exon derived microRNA675 (miR675) in prenatal muscle development remain to be examined. H19/Igf2 are in the same imprinting cluster with H19 expressed from the maternal allele while Igf2 expresses paternally. H19 contains a G-rich loop, and KH-type splicing regulatory protein (KHSRP) mediates the biogenesis of pre-miRNAs containing G-rich loops, which depends on its phosphorylation by AKT, a key mediator of IGF2 signalling. This study aims to depict the elusive function of these regulators that are affected by MO during embryonic myogenesis. METHODS: Single-cell transcriptomic sequencing and GeoMx spatial RNA sequencing were performed to identify the differentially expressed genes between embryos from MO and control (CT) mice. Both E11.5 and E13.5 embryos were collected and analysed to validate the sequencing data. The roles of H19 and miR657 in myogenesis were further analysed in P19 embryonic cells via CRISPR/dCas9-mediated H19 activation and inhibition. The epigenetic changes of H19 were analysed by methylated DNA immunoprecipitation, and allele-targeted analysis of H19 was performed by crossing C57BL/6J and CAST/EiJ mice. RESULTS: Transcriptomic analysis showed that MO embryos contained less differentiated myocytes (1.34%) than CT embryos (2.86%). Myogenesis-related GO biological processes were down-regulated in the MO embryonic myotome region. MO embryos showed lower expression of myogenic transcription factors such as Myf5, Myod1, Myog, Mef2c and Myh3 (p < 0.05). MO altered epigenetic modifications of the H19 genomic cluster, showing a decreased methylation level in H19 imprinting control region (p < 0.05) and a diallelic expression pattern of H19, which elevated its expression in MO embryos. Overexpression of H19 inhibited myogenesis in P19 cells, but miR675 promoted myogenesis, suggesting the critical regulatory roles of bioconversion of H19 to miR675. A KHSRP mediates the biogenesis of miR675, a process that relies on its phosphorylation by IGF2/AKT signalling. Knocking-down of KHSRP and inhibition of AKT abolished miR675 biogenesis. MO suppressed IGF2/AKT signalling and blocked KHSRP-dependent miR675 biogenesis in embryos. CONCLUSIONS: We found differential effects of H19 and miR675 on embryonic myogenesis. MO up-regulates H19 but blocks its miR675 bioconversion via suppressing IGF2/AKT/KHSRP signalling axis. Myogenesis in MO embryos was impeded due to the highly accumulated H19 and blocked miR675 biogenesis.

RNA, Long Noncoding↗

PubMed2026

Trimethylamine-producing microbe Bacillus megaterium KCTC 3007 promotes antitumor immunity in endometrial cancer via type I interferon response pathways.

BACKGROUND: Endometrial cancer (ECa) is one of the most common gynecologic malignancies, with limited therapeutic responses in metastatic or recurrent cases. The bacterial microbiota has emerged as a key modulator of carcinogenesis and antitumor immunity. However, the role of endometrial microbiota in ECa pathogenesis and prognosis remains poorly understood. METHODS: We performed comprehensive multi-omics analysis integrating metatranscriptomics, transcriptomics, and targeted metabolomics from 60 ECa and 18 benign patients. RNA sequencing enabled simultaneous profiling of active tissue-resident microbiota and host gene expression. Serum metabolomics was conducted on all patients. Identified microbial-metabolite associations were validated through in vitro co-culture experiments using peripheral blood mononuclear cells (PBMCs), cancer cell lines, RNA sequencing, and live cell imaging. RESULTS: ECa patients exhibited significantly altered microbial diversity and composition compared to benign controls. Through integrated multi-omics analysis, we identified Bacillus megaterium (BM) KCTC 3007 as a beneficial microbe associated with prolonged recurrence-free survival. In an exploratory analysis of ECa subtypes, Cupriavidus taiwanensis and Marinomonas primoryensis showed potential links to poor prognosis, although these observations warrant caution due to the limited size of certain subgroups. Tissue BM abundance positively correlated with serum trimethylamine N-oxide (TMAO) levels, particularly in postmenopausal women. In vitro experiments demonstrated that BM KCTC 3007 enhanced antitumor immunity by promoting interleukin and type I interferon expression, expanding CD8 + T cell populations, and increasing immune cell-tumor cell interactions. RNA sequencing revealed activation of interferon alpha response and immune cell proliferation pathways, with IFNAR1 identified as a key upstream regulator. TMAO treatment recapitulated these immune-activating effects, enhancing CD8 + T cell responses and preferentially inducing pyroptotic cancer cell death. CONCLUSIONS: We provide the first evidence that tissue-resident BM KCTC 3007 promotes antitumor immunity in ECa through TMAO production and subsequent type I interferon-mediated immune activation. This integrated multi-omics approach establishes a complete microbe-metabolite-host mechanistic pathway and highlights the therapeutic potential of TMAO-producing probiotic strains for ECa treatment. Video Abstract.

Female↗

PubMed2026

Unraveling a Diagnostic Enigma: A TECPR2 Case Solved Through Multi-Omic Genomics.

TECPR2 is a key regulator of autophagy, encoded by the TECPR2 gene. Pathogenic variants in this gene have been linked to a rare hereditary sensory and autonomic neuropathy with intellectual disability (HSAN9). We report a teenage female with a syndromic intellectual disability disorder associated with neuromuscular abnormalities. Multi-omics analysis including genomics, transcriptomics, and proteomics, together with muscle biopsy from the affected individual, were used in this clinical case. Through trio exome sequencing we identified two heterozygous variants in the TECPR2 gene, NM_014844.4: c.480G>A; p.(Gln160=) and c.2846C>A; p.(Ala949Glu). Both were classified as variants of uncertain significance due to the lack of supporting evidence for pathogenicity. Subsequent long-read sequencing phased the variants and confirmed they were in trans. Additional functional studies using RNAseq and proteomics analyses verified the pathogenicity of the variants. This case study demonstrated the value of a multi-omics assisted analysis, which complemented the traditional phenotype-first approach in reaching a definitive clinical diagnosis.

Humans↗

PubMed2025

Alternative Splicing in Mechanically Stretched Podocytes as a Model of Glomerular Hypertension.

KEY POINTS: Mechanical stretch induced over 3000 alternative splicing events in podocytes, affecting gene expression and protein abundance. Seventeen genes showed consistent splicing events across multiple analysis tools, with key isoform changes. Shroom3 and Myl6 underwent isoform switches under mechanical stretch, altering the C-terminal sequence and interaction properties of Myl6. BACKGROUND: Alterations in pre-mRNA splicing are crucial to the pathophysiology of various diseases. However, the effects of alternative splicing of mRNA on podocytes in hypertensive nephropathy are still unknown. The Sys_CARE project aimed to identify alternative splicing events involved in the development and progression of glomerular hypertension. METHODS: Murine podocytes were exposed to mechanical stretch, after which proteins and mRNA were analyzed by proteomics, RNA sequencing, and several bioinformatic alternative splicing tools. RESULTS: Using transcriptomic and proteomic analysis, we identified significant changes in gene expression and protein abundance because of mechanical stretch. RNA-Seq identified over 3000 alternative spliced genes after mechanical stretch, including all types of alternative splicing events. Among these, 17 genes exhibited an alternative splicing event across four different splicing analysis tools. From this group, we focused on Myl6, a component of the myosin protein complex, and Shroom3, an actin-binding protein essential for podocyte function. We identified two Shroom3 isoforms with significant expression changes under mechanical stretch, which was validated by quantitative RT-PCR and in situ hybridization. In addition, we observed an expression switch of two Myl6 isoforms after mechanical stretch, accompanied by an alteration in the C-terminal amino acid sequence. CONCLUSIONS: A comprehensive RNA-Seq analysis of mechanically stretched podocytes identified novel potential podocyte-specific biomarkers and highlighted significant alternative splicing events, notably in the mRNA of Shroom3 and Myl6.

podocyte↗

PubMed2026

Integrated Multi-omics Profiling of 2,4-dinitrochlorobenzene (DNCB)-induced Atopic Dermatitis in Mice Reveals a Coordinated Network of Barrier Dysfunction, Immune Activation, and Metabolic Reprogramming.

Atopic dermatitis (AD) is caused by a combination of epidermal barrier defect and immune imbalance. However, the molecular networks between these structural abnormalities and metabolic variations are unclear. This study aim of this research was to examine the concurrent molecular alterations in skin barrier damage and metabolic disorders in an AD-like mouse model by a multi-omics strategy. A 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model was established and the skin tissues were examined through the combination of transcriptomic, quantitative proteomic, and metabolomic analyses. Cross-omics correlation and network analyses were performed to identify consistently abnormal molecular pathways and crucial regulatory molecules. DNCB treatment caused severe epidermal hyperplasia, and prominent infiltration of CD3⁺ T cells, F4/80⁺ macrophages, and mast cells. Transcriptomic and proteomic analysis indicated significant disruption in keratinocyte differentiation, extracellular matrix organization, and cornified envelope formation pathways. Combined analysis detected 171 molecules which were simultaneously altered at both mRNA and protein levels, and network analysis identified FLG2 and KRT6B as central barrier-related molecules. Pathway enrichment analysis consistently showed the participation of AMPK and PPAR signaling pathways. Metabolomic analysis also revealed coordinated changes in lipid and amino acid metabolism which were closely associated with cornified envelope-associated genes and collagen-modifying enzymes. These findings indicate a close relationship between barrier, immune and metabolic regulation in DNCB-induced dermatitis and provide a multi-omics resource for future mechanistic studies of atopic skin inflammation.

Animals↗

PubMed2025

Cr3a, a candidate gene conferring fruit cracking resistance, was fine-mapped in an introgression line of Solanum lycopersicum L.

In the cultivation and production of tomato (Solanum lycopersicum L.), fruit cracking is a prevalent and detrimental issue that significantly impacts the esthetic quality and commercial value of the fruit. The complexity of the trait has resulted in a slow advancement in research aimed at identifying genes that influence tomato fruit cracking and the underlying regulatory mechanisms. In this study, a sub-introgression population for tomato crack-resistant fruit has been constructed from the cross between S. lycopersicum 1052 and Solanum pennellii LA0716, followed by 11 generations of selfing. Utilizing specifically designed InDel markers, the tomato crack-resistant gene, Cr3a, was fine-mapped, cloned, and its functionality was confirmed through transgenic and gene-knockout approaches. The precise localization of Cr3a was delineated to a 30 kb genomic region on chromosome 3, corresponding to the gene Sopen03g034650 in S. pennellii and Solyc03g115660.3 in the Heinz1706 variety. An integrated transcriptomic and metabolomic analysis of fruits with and without the Cr3a gene was finally conducted to elucidate the intricate regulatory mechanisms associated with Cr3a. The findings revealed a molecular regulatory network for tomato fruit crack resistance, characterized by 7 key metabolites, 13 pivotal genes, and 4 critical pathways: the phenylpropanoid biosynthesis pathway, the phenylalanine, tyrosine, and tryptophan biosynthesis pathway, the linolenic acid metabolism pathway, and the cysteine and methionine metabolism pathway. In summary, this research provides novel insights into the molecular underpinnings of tomato fruit crack resistance and holds substantial promise for accelerating the molecular breeding of tomatoes with enhanced fruit crack resistance.

Solanum lycopersicum↗

PubMed2024

Premeiotic 24-nt phasiRNAs are present in the Zea genus and unique in biogenesis mechanism and molecular function.

Reproductive phasiRNAs (phased, small interfering RNAs) are broadly present in angiosperms and play crucial roles in sustaining male fertility. While the premeiotic 21-nt (nucleotides) phasiRNAs and meiotic 24-nt phasiRNA pathways have been extensively studied in maize (Zea mays) and rice (Oryza sativa), a third putative category of reproductive phasiRNAs-named premeiotic 24-nt phasiRNAs-have recently been reported in barley (Hordeum vulgare) and wheat (Triticum aestivum). To determine whether premeiotic 24-nt phasiRNAs are also present in maize and related species and begin to characterize their biogenesis and function, we performed a comparative transcriptome and degradome analysis of premeiotic and meiotic anthers from five maize inbred lines and three teosinte species/subspecies. Our data indicate that a substantial subset of the 24-nt phasiRNA loci in maize and teosinte are already highly expressed at the premeiotic phase. The premeiotic 24-nt phasiRNAs are similar to meiotic 24-nt phasiRNAs in genomic origin and dependence on DCL5 (Dicer-like 5) for biogenesis, however, premeiotic 24-nt phasiRNAs are unique in that they are likely i) not triggered by microRNAs, ii) not loaded by AGO18 proteins, and iii) not capable of mediating PHAS precursor cleavage. In addition, we also observed a group of premeiotic 24-nt phasiRNAs in rice using previously published data. Together, our results indicate that the premeiotic 24-nt phasiRNAs constitute a unique class of reproductive phasiRNAs and are present more broadly in the grass family (Poaceae) than previously known.

Zea mays↗

PubMed2026

Insights into the mechanism of enhanced tetramethylpyrazine production in dehulled adlay fermented by Bacillus subtilis BJ3-2.

Tetramethylpyrazine (TTMP) is a vital bioactive alkaloid and characteristic flavor compound in fermented foods. Our previous study found that fermentation of adlay by Bacillus subtilis BJ3-2 efficiently accumulates TTMP, whereas the underlying high-yield mechanism remains unclear. This study investigated the fermentation characteristics, gene transcription and protein expression of B. subtilis BJ3-2 in dehulled adlay (BDA) and soybean (BSB), respectively, and elucidated the mechanism responsible for high-yield TTMP production. The results showed that glutamate, leucine and phenylalanine were major free amino acids in BDA. The TTMP yield in BDA at 48 h (6.11 mg/g dry weight) was 360-fold higher than that in BSB. Transcriptomic and proteomic analysis demonstrated that compared with the soybean substrate, dehulled adlay substrate significantly up-regulated the expression of alsSD and ilvBH genes and their encoding proteins in B. subtilis BJ3-2, which were involved in C5-branched dibasic acid metabolism, 2-oxocarboxylic acid metabolism, and valine, leucine and isoleucine biosynthesis. Meanwhile, acetoin degradation was inhibited by down-regulating acetoin dehydrogenase complex (acoABCL) in citrate cycle, glycolysis/gluconeogenesis and carbon metabolism. Additionally, nitrogen metabolism pathway was transcriptionally enhanced to guarantee sufficient ammonium supply. Notably, protein-protein interaction and molecular docking analyses revealed that acetohydroxyacid synthase (ilvBH) interacted tightly with α-acetolactate decarboxylase (alsD), potentially forming a metabolic channel for acetoin synthesis. In conclusion, the efficient synthesis of TTMP in BDA was primarily attributed to the high synthesis and low degradation of acetoin, and the moderate synthesis of ammonium/ammonia. This study provided a theoretical basis for the targeted and efficient biosynthesis of TTMP.

Bacillus subtilis↗

PubMed2026

Functional characterization of carbon dioxide receptors in the fall armyworm, Spodoptera frugiperda.

BACKGROUND: Carbon dioxide (CO2) is an important chemosensory cue involved in host plant recognition and environmental navigation in moths. In insects, CO2 detection is generally mediated by specific gustatory receptors (GRs). This study aimed to identify and functionally characterize CO2-related GRs in the fall armyworm, Spodoptera frugiperda. RESULTS: Three candidate GR genes, designated SfruGR1, SfruGR2, and SfruGR3, were identified through genomic and transcriptomic analyses. Phylogenetic analysis showed that these receptors clustered with conserved insect CO2 GRs and formed three distinct monophyletic clades. Quantitative real-time PCR revealed that SfruGR3 was expressed at significantly higher levels than SfruGR1 and SfruGR2 across multiple adult tissues and larval stages. Two-electrode voltage clamp recordings in Xenopus oocytes showed that only the co-expression of SfruGR1 + SfruGR3 among seven receptor combinations produced significant responses to bicarbonate ions (HCO₃-), which were used to represent dissolved CO2. Electrolabialpalpography assays demonstrated that FAW labial palps responded to CO2 in a concentration-dependent manner, with 1% CO2 eliciting the strongest electrophysiological response, especially in females. In Y-tube olfactometer assays, males were significantly attracted to 1% CO2, whereas females showed only a weak behavioral response. CONCLUSION: These results indicate that SfruGR1 and SfruGR3 are key components of CO2 perception in FAW. This study provides new insight into the molecular and behavioral mechanisms of CO2 sensing in this destructive agricultural pest. © 2026 Society of Chemical Industry.

Spodoptera frugiperda↗

PubMed2026

NFS1 activates PI3K/AKT/mTOR signaling to upregulate GPX4 expression and enhance ferroptosis resistance in osteosarcoma.

Osteosarcoma continues to exhibit poor survival outcomes due to chemoresistance and metastasis, with metabolic reprogramming and ferroptosis resistance being key features of tumor heterogeneity, yet their upstream regulators remain poorly defined. NFS1, a cysteine desulfurase essential for iron-sulfur cluster biogenesis, protects multiple cancers from ferroptosis, but its role in osteosarcoma is unknown. In this study, we performed a transcriptomic meta-analysis and found that NFS1 expression was significantly upregulated in osteosarcoma tissues, with further elevation in metastatic lesions, and high NFS1 expression correlated with poor overall survival. Genome‑wide CRISPR screening data revealed a marked NFS1 dependency in osteosarcoma cell lines. Functionally, NFS1 promoted cell proliferation, migration, and invasion, whereas its knockdown suppressed these phenotypes. Using single‑cell RNA sequencing data from 27 osteosarcoma specimens, we applied a multi‑algorithm glycolytic scoring framework and observed NFS1 enrichment in highly glycolytic malignant cells, along with an association with PI3K/AKT/mTOR pathway activation. Mechanistically, NFS1 selectively enhanced PI3K, AKT, and mTOR phosphorylation without altering total protein levels, and upregulated GPX4, a central ferroptosis suppressor, leading to elevated ferroptosis resistance scores in NFS1‑high malignant cells. Collectively, these findings identify a previously unrecognized NFS1-PI3K/AKT/mTOR-GPX4 regulatory axis in osteosarcoma, linking metabolic reprogramming to ferroptosis resistance, and suggest that NFS1 functions as an oncogenic driver, as well as a promising prognostic biomarker and therapeutic target in osteosarcoma.

Humans↗

PubMed1997

Characterization of the yeast transcriptome.

We have analyzed the set of genes expressed from the yeast genome, herein called the transcriptome, using serial analysis of gene expression. Analysis of 60,633 transcripts revealed 4,665 genes, with expression levels ranging from 0.3 to over 200 transcripts per cell. Of these genes, 1981 had known functions, while 2684 were previously uncharacterized. The integration of positional information with gene expression data allowed for the generation of chromosomal expression maps identifying physical regions of transcriptional activity and identified genes that had not been predicted by sequence information alone. These studies provide insight into global patterns of gene expression in yeast and demonstrate the feasibility of genome-wide expression studies in eukaryotes.

Cell Cycle↗

PubMed2026

A-to-I RNA editing remodels 5'-UTR initiation codons to tune translational output.

A-to-I RNA editing is a prevalent post-transcriptional modification in higher eukaryotes that converts adenosine to inosine within RNA molecules. Because inosine is interpreted as guanosine during translation, editing can alter codon identity and potentially influence translation initiation signals. Here, we examined whether A-to-I editing within the 5' untranslated region (5'-UTR) can remodel upstream initiation codons and thereby tune downstream translation. Using luciferase-based reporter systems, we show that AUA-to-AUI editing generates an initiation-competent inosine-containing codon, whereas AUG-to-IUG editing markedly attenuates initiation and can relieve uORF-mediated repression. Quantitative in vitro and cellular assays establish the initiation hierarchy AUA < AUI < AUG, with IUG exhibiting strongly reduced initiation efficiency. Importantly, AUI-mediated upstream initiation did not behave like a canonical AUG-initiated uORF in the tested contexts; its effect on downstream ORF translation was modest and context-dependent. Transcriptome-wide bioinformatic analysis identified endogenous human transcripts whose 5'-UTRs harbor editing sites compatible with initiation-codon gain or attenuation. Reporter validation using native 5'-UTR sequences supports the possibility that editing-dependent initiation-codon remodeling can tune translational output in living cells, particularly through AUG-to-IUG-mediated derepression. Together, these findings establish a reporter-based framework in which A-to-I editing can remodel 5'-UTR initiation codons, while highlighting the need for endogenous protein-level and native-locus validation to determine physiological relevance.

RNA Editing↗

PubMed2024

Premeiotic 24-nt phasiRNAs are present in the Zea genus and unique in biogenesis mechanism and molecular function.

Reproductive phasiRNAs are broadly present in angiosperms and play crucial roles in sustaining male fertility. While the premeiotic 21-nt phasiRNAs and meiotic 24-nt phasiRNA pathways have been extensively studied in maize (Zea mays) and rice (Oryza sativa), a third putative category of reproductive phasiRNAs-named premeiotic 24-nt phasiRNAs-have recently been reported in barley (Hordeum vulgare) and wheat (Triticum aestivum). To determine whether premeiotic 24-nt phasiRNAs are also present in maize and related species and begin to characterize their biogenesis and function, we performed a comparative transcriptome and degradome analysis of premeiotic and meiotic anthers from five maize inbred lines and three teosinte species/subspecies. Our data indicate that a substantial subset of the 24-nt phasiRNA loci in maize and teosinte are already highly expressed at premeiotic phase. The premeiotic 24-nt phasiRNAs are similar to meiotic 24-nt phasiRNAs in genomic origin and dependence on DCL5 for biogenesis, however, premeiotic 24-nt phasiRNAs are unique in that they are likely (i) not triggered by microRNAs, (ii) not loaded by AGO18 proteins, and (iii) not capable of mediating cis-cleavage. In addition, we also observed a group of premeiotic 24-nt phasiRNAs in rice using previously published data. Together, our results indicate that the premeiotic 24-nt phasiRNAs constitute a unique class of reproductive phasiRNAs and are present more broadly in the grass family (Poaceae) than previously known.

Maize↗

PubMed2025

Functional characterization of the MED12 p.Arg1138Trp variant in females: implications for neural development and disease mechanism.

BACKGROUND: Seven female individuals with multiple congenital anomalies, developmental delay and/or intellectual disability have been found to have a genetic variant of uncertain significance in the mediator complex subunit 12 gene (MED12 c.3412C>T, p.Arg1138Trp). The functional consequence of this genetic variant in disease is undetermined, and insight into disease mechanism is required. METHODS: We identified a de novo MED12 p.Arg1138Trp variant in a female patient and compared disease phenotypes with six female individuals identified in the literature. To investigate affected biological pathways, we derived two induced pluripotent stem cell (iPSC) lines from the patient: one expressing wildtype MED12 and the other expressing the MED12 p.Arg1138Trp variant. We performed neural disease modelling, transcriptomics and protein analysis, comparing healthy and variant cells. RESULTS: When comparing the two cell lines, we identified altered gene expression in neural cells expressing the variant, including genes regulating RNA polymerase II activity, transcription, pre-mRNA processing, and neural development. We also noted a decrease in MED12L expression. Pathway analysis indicated temporal delays in axon development, forebrain differentiation, and neural cell specification with significant upregulation of pre-ribosome complex gene pathways. CONCLUSION: In a human neural model, expression of MED12 p.Arg1138Trp altered neural cell development and dysregulated the pre-ribosome complex providing functional evidence of disease aetiology and mechanism in MED12-related disorders.

Humans↗