RNA Editing Research Articles

Exploring the role of ADAMTSL2 across multiple cancer types: A pan-cancer analysis and validated in colorectal cancer

BackgroundRecent studies have established a correlation between ADAMTSL2 (ADAMTS-like 2) and the development of various cancers. This study aims to conduct a comprehensive pan-cancer analysis in 37 cancer types and investigate its potential role in colon and rectal adenocarcinoma (COADREAD).MethodPan-cancer and mutation data were sourced from The Cancer Genome Atlas (TCGA) database and analyzed using Sangerbox analysis platform. We explored the expression patterns and prognostic implications of ADAMTSL2, and investigated its relationships with tumor heterogeneity, stemness, immune checkpoint genes, immune cell infiltration, RNA modifications, and mutational profiles across different cancers. Additionally, with Ethics Committee approval, we conducted immunohistochemical (IHC) analysis on 120 COADEAD samples to evaluate ADAMTSL2 expression and its association with clinicopathological parameters.ResultsADAMTSL2 expression was positively correlated with the hazard ratio of OS, DSS, DFI and PFI for ESCA and COADREAD. A negative correlation was observed between ADAMTSL2 expression and NEO levels in COAD. Gene alterations in ADAMTSL2 were observed, with a mutation frequency of 5.0% in COAD. There is a significant correlation between ADAMTSL2 expression and immune cell infiltration in a variety of cancers. The expression level of ADAMTSL2 protein was associated with T stage, N stage, M stage (p < 0.05). Kaplan‒Meier survival curves demonstrated that the high ADAMTSL2 group had a shorter OS time (p = 0.047) and progression free survival time (p = 0.026) than the low ADAMTSL2 group.ConclusionIn summary, we conducted a comprehensive pan-cancer analysis of ADAMTSL2 and we demonstrated that ADAMTSL2 may serve as a novel prognostic biomarker and immunotherapy target in COADREAD.

METTL3-regulated m6A modification of lncRNA E230001N04Rik is involved in myofibroblast differentiation in arsenic-induced pulmonary fibrosis through promoting senescence of lung epithelial cells

Arsenic is a toxic agent that causes respiratory damage. Long non-coding RNAs (lncRNAs) are non-coding transcripts that adsorb specific miRNAs and regulate biological processes of human diseases. N6-Methyladenosine (m6A) is an internal modification of RNAs. However, there are few reports about lncRNAs and m6A modifications as co-regulators of pulmonary fibrosis. For 6 months, C57BL/6 mice were given water containing 0, 10, or 20 ppm arsenite. meRIP-seq and lncRNA-seq analyses showed that the m6A levels of the lncRNA E230001N04Rik were higher, and the levels of E230001N04Rik itself were lower in the high-dose arsenite group than in the controls. Murine lung epithelial 12 (MLE12) cells, exposed to 8 μM arsenite for 8 passages, had elevated METTL3 and miR-20b-3p and low E230001N04Rik. Arsenite induced cellular senescence, as demonstrated by secretion of factors related to the senescence-associated secretory phenotype (SASP). Arsenite-treated MLE12 cells co-cultured with primary lung fibroblasts (PLFs) caused myofibroblast differentiation. These data show that METTL3 reduces E230001N04Rik expression via controlling its m6A levels, which regulate miR-20b-3p and mediate the senescence of alveolar epithelial cells (AECs). Thereby, E230001N04Rik is involved in the arsenite-induced myofibroblast differentiation and in pulmonary fibrosis. These observations provide a prospective mechanism for chronic pulmonary disease caused by arsenite.

DEMINING: A deep learning model embedded framework to distinguish RNA editing from DNA mutations in RNA sequencing data.

Precise calling of promiscuous adenosine-to-inosine RNA editing sites from transcriptomic datasets is hindered by DNA mutations and sequencing/mapping errors. Here, we present a stepwise computational framework, called DEMINING, to distinguish RNA editing and DNA mutations directly from RNA sequencing datasets, with an embedded deep learning model named DeepDDR. After transfer learning, DEMINING can also classify RNA editing sites and DNA mutations from non-primate sequencing samples. When applied in samples from acute myeloid leukemia patients, DEMINING uncovers previously underappreciated DNA mutation and RNA editing sites; some associated with the upregulated expression of host genes or the production of neoantigens.

Complete chloroplast genomes of Desmidorchis penicillata (Deflers) plowes and Desmidorchis retrospiciens Ehrenb.: comparative and phylogenetic analyses among subtribe Stapeliinae (Ceropegieae, Asclepiadoideae, Apocynaceae)

The succulent shrubs Desmidorchis penicillata and D. retrospiciens, part of the taxonomically challenging genus Desmidorchis, are well‐known for their ecological resilience and medicinal significance. This study sequences the first complete chloroplast genomes of these species, shedding light on their genomic characteristics and evolutionary relationships. The circular genomes of D. penicillata (161 776 bp) and D. retrospiciens (162 277 bp) display a quadripartite structure typical of Angiosperms. Gene content, order, and GC content are consistent, featuring 114 unique genes, including 80 protein‐coding, 30 transfer RNAs, and four ribosomal RNAs genes. Codon usage analysis underscores A/U‐rich preferences, while RNA editing sites, predominantly in ndhB and ndhD genes, suggest post‐transcriptional modifications. Analysis of long repeated sequences reveals a predominance of forward and palindromic repeats. Simple sequence repeats (SSRs), particularly A/T motifs, are abundant, with high presence of mononucleotide, offering potential molecular markers. Comparative analysis with their relatives in subtribe Stapeliinae identifies mutational hotspots such as ycf1, ndhF, trnG(GCC)‐trnfM(CGA) and ndhG‐ndhI that could be potential DNA barcoding markers. The inverted repeat (IR) boundaries analysis revealed an expansion of IR on the small single copy region, leading to the formation of a pseudogene. Overall, substitution rate analysis indicated purifying selection, with a few genes (rpl22, clpP and rps11) showing signatures of positive selection. Additionally, the phylogenetic analysis positioned Desmidorchis within the Stapeliinae clade and strongly supported the sister relationship between D. penicillata and D. retrospiciens. This study provides comprehensive molecular data for future research in Desmidorchis.

Identification and validation of an m7G-related lncRNAs signature for predicting prognosis, immune response and therapy landscapes in ovarian cancer.

Ovarian cancer is the most mortality malignancy in gynecology. N7-methylguanosine (m7G) is one of the most prevalent RNA modifications in the development and progression of cancer. The aim of this study is to investigate the effect of m7G-related lncRNA on ovarian cancer in terms of instruction prognosis and immunotherapy. After integrating and processing the RNA expression profiles with the clinical sample information in the TCGA database, we initially screened to the m7G-related lncRNAs by Spearman correlation analysis, and subsequently obtained a prognostic model constructed by five m7G-related lncRNAs with Univariate Cox analysis, LASSO regression analysis, and Multivariate Cox regression analysis, after which we further evaluated and validated the prognostic value of the model using Kaplan-Meier survival analysis, Principal component analysis, Nomogram, and ROC curve. In addition, based on this risk model, we explored the differentially enriched pathways and functions of the high and low risk groups, and characterized the immune cells, immune functions, gene mutations, and drug sensitivity between the two groups. After a series of rigorous filtering, we finally attained a prognostic risk model consisting of KRT7-AS, USP30-AS1, ZFHX4-AS1, ACAP2-IT1, and TWSG1-DT which is excellent in predicting the prognostic survival of ovarian cancer patients as well as existing as an independent prognostic factor. Moreover, the model has certain relevance in the immune cells and functions between high and low risk groups, and simultaneously, the signature has the role of guiding the option of immunotherapy and chemotherapeutic drugs. Altogether, our study established a tight connection between m7G-associated lncRNAs and ovarian cancer, with potential that the prognostic patterns contribute to steering the prognosis of ovarian cancer patients, measuring the efficacy of immunotherapeutic approaches, and detecting effective chemotherapeutic agents.

Post-Translational Modifications of RNA-Modifying Proteins in Cellular Dynamics and Disease Progression.

RNA-modifying proteins, classified as "writers," "erasers," and "readers," dynamically modulate RNA by adding, removing, or interpreting chemical groups, thereby influencing RNA stability, functionality, and interactions. To date, over 170 distinct RNA chemical modifications and more than 100 RNA-modifying enzymes have been identified, with ongoing research expanding these numbers. Although significant progress has been made in understanding RNA modification, the regulatory mechanisms that govern RNA-modifying proteins themselves remain insufficiently explored. Post-translational modifications (PTMs) such as phosphorylation, ubiquitination, and acetylation are crucial in modulating the function and behavior of these proteins. However, the full extent of PTM influence on RNA-modifying proteins and their role in disease development remains to be fully elucidated. This review addresses these gaps by offering a comprehensive analysis of the roles PTMs play in regulating RNA-modifying proteins. Mechanistic insights are provided into how these modifications alter biological processes, contribute to cellular function, and drive disease progression. In addition, the current research landscape is examined, highlighting the therapeutic potential of targeting PTMs on RNA-modifying proteins for precision medicine. By advancing understanding of these regulatory networks, this review seeks to facilitate the development of more effective therapeutic strategies and inspire future research in the critical area of PTMs in RNA-modifying proteins.

FTO/IGF2BP2-mediated N6 methyladenosine modification in invasion and metastasis of thyroid carcinoma via CDH12.

Epigenetic reprogramming plays a critical role in cancer progression of cancer, and N6-methyladenosine (m6A) is the most common RNA modification in eukaryotes. The purpose of this study was to explore the related modification mode of m6A regulator construction and evaluate the invasion and migration of thyroid cancer. Our results showed that m6A levels were significantly increased in papillary thyroid cancer (PTC) and anaplastic thyroid cancer (ATC) samples, which may have been induced by the down-regulation of demethylase fat mass and obesity-associated gene (FTO). Moreover, FTO inhibited PTC and ATC invasion and metastasis through the epithelial-to-mesenchymal transition (EMT) pathway in vivo and in vitro. Mechanistically, an m6A-mRNA epitranscriptomic microarray showed that Cadherin 12 (CDH12) is the key target gene mediated by FTO in an m6A-dependent manner. CDH12 promotes invasion and metastasis through the EMT pathway in thyroid cancer, both in vivo and in vitro. Furthermore, we found that insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) is an important m6A reading protein, that regulates the stability of CDH12 mRNA and mediates EMT progression, thereby promoting the invasion and metastasis of PTC and ATC. Thus, FTO, IGF2BP2 and CDH12 may be effective therapeutic targets for PTC and ATC with significant invasion or distant metastasis. Schematic summary of FTO-IGF2BP2 axis in modulation of CDH12 mRNA m6A and upregulation of CDH12 expression in the invasion and metastasis of thyroid carcinoma.

A comprehensive atlas of pig RNA editome across 23 tissues reveals RNA editing affecting interaction mRNA-miRNAs.

RNA editing is a co-transcriptional/post-transcriptional modification that is mediated by the ADAR enzyme family. Profiling of RNA editing is very limited in pigs. In this study, we collated 3813 RNA-seq data from the public repositories across 23 tissues and carried out comprehensive profiling of RNA editing in pigs. In total, 127,927 A-to-I RNA-editing sites were detected. Our analysis showed that 98.2% of RNA-editing sites were located within repeat regions, primarily within the pig-specific SINE retrotransposon PRE-1/Pre0_SS elements. Subsequently, we focused on analyzing specific RNA-editing sites (SESs) in skeletal muscle tissues. Functional enrichment analyses suggested that they were enriched in signaling pathways associated with muscle cell differentiation, including DMD, MYOD1, and CAV1 genes. Furthermore, we discovered that RNA editing event in the 3'UTR of CFLAR mRNA influenced miR-708-5p binding in this region. In this study, the panoramic RNA-editing landscape of different tissues of pigs was systematically mapped, and RNA-editing sites and genes involved in muscle cell differentiation were identified. In summary, we identified modifications to pig RNA-editing sites and provided candidate targets for further validation.

HNRNPC mediates lymphatic metastasis of cervical cancer through m6A-dependent alternative splicing of FOXM1

Cervical cancer (CCa) patients with lymph node (LN) metastasis face poor prognoses and have limited treatment options. Aberrant N6-methyladenosine (m6A) modification of RNAs are known to promote tumor metastasis, but their role in CCa remains unclear. Our study reveals that HNRNPC, an alternative splicing (AS) factor and m6A reader, increases tumor-related variants through m6A-dependent manner, thereby promoting lymphatic metastasis in CCa. We found that HNRNPC overexpression correlates with lymphatic metastasis and poorer prognoses in CCa patients. Functionally, knocking down HNRNPC markedly inhibited the migration and invasion of several CCa cell lines, while supplementing HNRNPC restored the malignant phenotypes of these cells. Mechanistically, HNRNPC regulates exon skipping of FOXM1 by binding to its m6A-modified motif. Mutating the m6A site on FOXM1 weakened the interaction between HNRNPC and FOXM1 pre-RNA, leading to a reduction in the metastasis-related FOXM1-S variant. In conclusion, our findings demonstrate that m6A-dependent alternative splicing mediated by HNRNPC is essential for lymphatic metastasis in CCa, potentially providing novel clinical markers and therapeutic strategies for patients with advanced CCa.

NSUN2 regulates Wnt signaling pathway depending on the m5C RNA modification to promote the progression of hepatocellular carcinoma.

5-Methylcytosine (m5C) RNA modification is a highly abundant and important epigenetic modification in mammals. As an important RNA m5C methyltransferase, NOP2/Sun-domain family member 2 (NSUN2)-mediated m5C RNA modification plays an important role in the regulation of the biological functions in many cancers. However, little is known about the biological role of NSUN2 in hepatocellular carcinoma (HCC). In this study, we found that the expression of NSUN2 was significantly upregulated in HCC, and the HCC patients with higher expression of NSUN2 had a poorer prognosis than those with lower expression of NSUN2. NSUN2 could affect the tumor immune regulation of HCC in several ways. In vitro and in vivo experiments confirmed that NSUN2 knockdown significantly decreased the abilities of proliferation, colony formation, migration and invasion of HCC cells. The methylated RNA immunoprecipitation-sequencing (MeRIP-seq) showed NSUN2 knockdown significantly affected the abundance, distribution, and composition of m5C RNA modification in HCC cells. Functional enrichment analyses and in vitro experiments suggested that NSUN2 could promote the HCC cells to proliferate, migrate and invade by regulating Wnt signaling pathway. SARS2 were identified via the RNA immunoprecipitation-sequencing (RIP-Seq) and MeRIP-seq as downstream target of NSUN2, which may play an important role in tumor-promoting effect of NSUN2-mediated m5C RNA modification in HCC. In conclusion, NSUN2 promotes HCC progression by regulating Wnt signaling pathway and SARS2 in an m5C-dependent manner.

Deciphering the multi- partite mitochondrial genome of Crataegus pinnatifida: insights into the evolution and genetics of cultivated Hawthorn

Flowering plant (angiosperm) mitochondrial genomes are remarkably dynamic in their structures. We present the complete mitochondrial genome of hawthorn (Crataegus pinnatifida Bunge), a shrub that bears fruit and is celebrated for its extensive medicinal history. We successfully assembled the hawthorn mitogenome utilizing the PacBio long-read sequencing technique, which yielded 799,862 reads, and the Illumina novaseq6000 sequencing platform, which producing 6.6 million raw paired reads. The C. pinnatifida mitochondria sequences encompassed a total length of 440,295 bp with a GC content of 45.42%. The genome annotates 54 genes, including 34 that encode proteins, 17 that encode tRNA, and three genes for rRNA. A fascinating interplay was observed between the chloroplast and mitochondrial genomes, which share 17 homologous sequences sequences that rotal 1,933 bp. A total of 134 SSRs, 22 tandem repeats and 42 dispersed repeats were identified in the mitogenome. Four conformations of C. pinnatifida mitochondria sequences recombination were verified through PCR experiments and Sanger sequencing, and C. pinnatifida mitogenome is more likely to be assembled into three circular-mapping chromosomes. All the RNA editing sites that were identified C-U edits, which predominantly occurred at the first and second positions of the codons. Phylogenetic and collinearity analyses identified the evolutionary trajectory of C. pinnatifida, which reinforced the genetic identity of the hawthorn section. This unveiling of the unique multi-partite structure of the hawthorn mitogenome offers a foundational reference for future study into the evolution and genetics of C. pinnatifida.

Genome-wide identification of m6A-related gene family and the involvement of TdFIP37 in salt stress in wild emmer wheat.

The genomic organization, phylogenetic relationship, expression patterns, and genetic variations of m6A-related genes were systematically investigated in wild emmer wheat and the function of TdFIP37 regulating salt tolerance was preliminarily determined. m6A modification is one of the most abundant and crucial RNA modifications in eukaryotics, playing the indispensable role in growth and development as well as stress response in plants. However, its significance in wild emmer wheat remains elusive. Here, a genome-wide search of m6A-related genes was conducted in wild emmer wheat to obtain 64 candidates, including 21 writers, 17 erasers, and 26 readers. Phylogenetic and collinearity analysis demonstrated that segmental duplication and polyploidization contributed mainly to the expansion of m6A-related genes in wild emmer. A number of cis-acting elements involving in stress and hormonal regulation were found in the promoter regions of them, such as MBS, LTR, and ABRE. Genetic variation of them was also investigated using resequencing data and obvious genetic bottleneck was occurred on them during wild emmer wheat domestication process. Furthermore, the salt-responsive candidates were investigated through RNA-seq data and qRT-PCR validation using the salt-tolerant and -sensitive genotypes and the co-expression analysis showed that they played the hub role in regulating salt stress response. Finally, the loss-function mutant of Tdfip37 displayed the significantly higher salt-sensitive compared to WT and then RNA-seq analysis demonstrated that FIP37 mediated the MAPK pathway, hormone signal transduction, as well as transcription factor to regulate salt tolerance. This study provided the potential m6A genes for functional analysis, which will contribute to better understand the regulatory roles of m6A modification and also improve the salt tolerance from the perspective of epigenetic approach in emmer wheat and other crops.

The RNA m5C methyltransferase NSUN1 modulates human malaria gene expression during intraerythrocytic development.

Plasmodium falciparum is the most damaging malaria pathogen and brings a heavy burden to global health. Host switching and morphological changes in P. falciparum are dependent on an effective gene expression regulatory system. C5 methylation of cytosines is a common RNA modification in eukaryotes, and the NSUN family are essential m5C modification executors. Currently, little is known about this family in Plasmodium spp. In this study, we focus on exploring the function of PfNSUN1 protein. An efficient CRISPR/Cas9 gene editing technique was applied to construct the PfNSUN1 knockdown strain. The knockdown efficiency was confirmed by growth curves and western blot experiments. The knockdown transcriptome data was acquired to find differentially expressed genes, and target genes of PfNSUN1 protein were identified by RNA immunoprecipitation and high-throughput sequencing experiments. The efficiency of PfNSUN1 protein down-regulated was about 34%. RNA-seq data revealed that differentially expressed genes were mainly down-regulated. And there were 224, 278, 556 genes that were down-regulated with more than 2-fold changes and p-adj<0.05 at ring, trophozoite and schizont stages, respectively. PfNSUN1 protein was significantly enriched on 154 target genes, including 28S ribosomal RNA and pfap2-g5 transcription factor. PfNSUN1 is a crucial RNA post-transcriptional modification protein in P. falciparum. It plays a pivotal role in regulating gene expression and parasite growth by targeting 28S ribosomal RNA and pfap2-g5 transcription factor.

β-Cyclodextrin-Modified Laser-Induced Graphene Electrode for Detection of N6-Methyladenosine in RNA.

Laser-induced graphene (LIG) possesses characteristics of easy handling, miniaturization, and unique electrical properties. We modified the surface of LIG by electropolymerizing β-cyclodextrin (β-CD), which was used to immobilize antibodies on the electrode surface for highly sensitive detection of targets. N6-methyladenosine (m6A) is the most prevalent reversible modification in mammalian messenger RNA and noncoding RNA, influencing the development of various cancers. Here, β-CD was electropolymerized to immobilize the anti-m6A antibody, which subsequently recognized the target m6A. This was integrated into the catalytic hydrogen peroxide-hydroquinone (H2O2-HQ) redox system using phos-tag-biotin to generate electrochemical signals from streptavidin-modified horseradish peroxidase (SA-HRP). Under optimal conditions, the biosensor exhibited a linear range from 0.1 to 100 nM with a minimum detection limit of 96 pM. The method was successfully applied to the recovery analysis of m6A from HeLa cells through spiking experiments and aims to inspire strategies for point-of-care testing (POCT).

6544 M6A methylation of PLCβ in the hypothalamus regulates GnRH synthesis and secretion by interfering Ca2+ signaling pathway

Abstract Disclosure: X. Yin: None. S. Zang: None. P. Li: None. Backgrounds: In recent years, the incidence of precocious puberty has increased rapidly, posing a serious threat to girls' physical and mental health. Epigenetic changes, especially m6A methylation modification, may be an important influencing factor. Researches had found that m6A modification plays an irreplaceable role in the development and functional homeostasis of the nervous system. A variety of factors could changed RNA m6A level in the hypothalamus and affect the process of adolescent sexual development. In the study,we aimed to explore the specific role of m6A methylation in precocious puberty, and to identify its downstream target genes by multi-omics approach and to verify its function. Hypothesis The demethylase FTO regulated the m6A modification of the target gene in the hypothalamus to affect the synthesis and secretion of GnRH and regulate the initiation of puberty. Methods: The modification abundance of m6A was investigated by the girls with central precious puberty (CPP). The changes of m6A modification in total RNA and the expression of important modulator genes were detected by colorimetry and qRT-PCR respectively in the hypothalamic ARC nucleus of female rats at three different developmental stages (juvenile, early puberty and puberty) and precocious rat model. MeRIP and mRNA sequencing was used to screen target genes which related to puberty development. Knockdown or overexpression of FTO were constructed using plasmid or lentivirus transfection. The target mRNA targeted regulated by FTO was verified with RNA-seq, qRT-PCR, WB and Flow cytometry. Results This study confirmed that the level of RNA m6A in the peripheral blood of the precocious group was significantly higher than that of the control group. The level of RNA m6A in the hypothalamus of female rats gradually increases with the development of puberty, and the expression of demethylase gradually decreases. MeRIP-seq combined with mrNA-seq screening analysis showed that the m6A modification of PLCβ in the ARC nucleus of the hypothalamus was reduced, and its mRNA expression was significantly increased in sexually precocious female rats. Combined with bioinformatics analysis, it was found that there were multiple m6A modified motif sites on the mRNA of PLCβ, and luciferase experiment confirmed that there was a regulatory relationship between them. After over-expressing FTO, the mRNA and protein expression of PLCβ were significantly increased, and the up-regulation of FTO expression induced a significant increase in intracellular Ca2+ concentration, the expression of CAM, and the activation of Ca2+ signaling pathway. Conclusions In the ARC nucleus of the hypothalamus, FTO affects the synthesis and secretion of GnRH by regulating the m6A modification level of PLCβ through the Ca2+ signaling pathway, and interferes with the initiation of female sexual development. Presentation: 6/1/2024

Unveiling fungal strategies: Mycoremediation in multi-metal pesticide environment using proteomics

Micropollutants, such as heavy metals and pesticides, inhibit microbial growth, threatening ecosystems. Yet, the mechanism behind mycoremediation of the pesticide lindane and multiple metals (Cd, Total Cr, Cu, Ni, Pb, Zn) remains poorly understood. In our study, we investigated cellular responses in Aspergillus fumigatus PD-18 using LC-MS/MS, identifying 2190 proteins, 1147 of which were consistently present under both stress conditions. Specifically, Cu-Zn superoxide dismutase and heat shock proteins were up-regulated to counter oxidative stress and protein misfolding. Proteins involved in intracellular trafficking, secretion, and vesicular transport; RNA processing and modification showed enhanced abundance and regulating stress response pathways. Additionally, haloalkane dehalogenase and homogentisate 1,2-dioxygenase played pivotal roles in lindane mineralization. Bioinformatics analysis highlighted enriched pathways such as Glyoxylate and dicarboxylate metabolism and Purine metabolism, that are crucial for combating adverse environments. We identified the hub protein 26 S proteasome regulatory subunit complex as potential biomarker and remedial targets for mycoremediation of wastewater, suggesting practical applications for environmental remediation.

Emerging Orchestrator of Ecological Adaptation: m6A Regulation of Post-Transcriptional Mechanisms.

Genetic mechanisms have been at the forefront of our exploration into the substrate of adaptive evolution and phenotypic diversification. However, genetic variation only accounts for a fraction of phenotypic variation. In the last decade, the significance of RNA modification mechanisms has become more apparent in the context of organismal adaptation to rapidly changing environments. RNA m6A methylation, the most abundant form of RNA modification, is emerging as a potentially significant player in various biological processes. Despite its fundamental function to regulate other major post-transcriptional mechanisms such as microRNA and alternative splicing, its role in ecology and evolution has been understudied. This review highlights the potential importance of m6A RNA methylation in ecological adaptation, emphasising the need for further research, especially in natural systems. We focus on how m6A not only affects mRNA fate but also influences miRNA-mediated gene regulation and alternative splicing, potentially contributing to organismal adaptation. The aim of this review is to synthesise key background information to enhance our understanding of m6A mechanisms driving species survival in dynamic environments and motivate future research into the dynamics of adaptive RNA methylation.

NAT10/ac4C/JunB facilitates TNBC malignant progression and immunosuppression by driving glycolysis addiction

BackgroundN4-Acetylcytidine (ac4C), a highly conserved post-transcriptional mechanism, plays a pivotal role in RNA modification and tumor progression. However, the molecular mechanism by which ac4C modification mediates tumor immunosuppression remains elusive in triple-negative breast cancer (TNBC).MethodsNAT10 expression was analyzed in TNBC samples in the level of mRNA and protein, and compared with the corresponding normal tissues. ac4C modification levels also measured in the TNBC samples. The effects of NAT10 on immune microenvironment and tumor metabolism were investigated. NAT10-mediated ac4C and its downstream regulatory mechanisms were determined in vitro and in vivo. The combination therapy of targeting NAT10 in TNBC was further explored.ResultsThe results revealed that the loss of NAT10 inhibited TNBC development and promoted T cell activation. Mechanistically, NAT10 upregulated JunB expression by increasing ac4C modification levels on its mRNA. Moreover, JunB further up-regulated LDHA expression and facilitated glycolysis. By deeply digging, remodelin, a NAT10 inhibitor, elevated the surface expression of CTLA-4 on T cells. The combination of remodelin and CTLA-4 mAb can further activate T cells and inhibite tumor progression.ConclusionTaken together, our study demonstrated that the NAT10-ac4C-JunB-LDHA pathway increases glycolysis levels and creates an immunosuppressive tumor microenvironment (TME). Consequently, targeting this pathway may assist in the identification of novel therapeutic strategies to improve the efficacy of cancer immunotherapy.

Maintenance of X chromosome inactivation after T cell activation requires NF-κB signaling.

X chromosome inactivation (XCI) balances X-linked gene dosage between sexes. Unstimulated T cells lack cytological enrichment of X-inactive specific transcript (Xist) RNA and heterochromatic modifications on the inactive X chromosome (Xi), which are involved in maintenance of XCI, and these modifications return to the Xi after stimulation. Here, we examined allele-specific gene expression and epigenomic profiles of the Xi in T cells. We found that the Xi in unstimulated T cells is largely dosage compensated and enriched with the repressive H3K27me3 modification but not the H2AK119-ubiquitin (Ub) mark. Upon T cell stimulation mediated by both CD3 and CD28, the Xi accumulated H2AK119-Ub at gene regions of previous H3K27me3 enrichment. T cell receptor (TCR) engagement, specifically NF-κB signaling downstream of the TCR, was required for Xist RNA localization to the Xi. Disruption of NF-κB signaling in mouse and human T cells using genetic deletion, chemical inhibitors, and patients with immunodeficiencies prevented Xist/XIST RNA accumulation at the Xi and altered X-linked gene expression. Our findings reveal a previously undescribed connection between NF-κB signaling pathways, which affects XCI maintenance in T cells in females.

The mitochondrial genome of Lavandula angustifolia Mill. (Lamiaceae) sheds light on its genome structure and gene transfer between organelles

BackgroundLavandula angustifolia holds importance as an aromatic plant with extensive applications spanning the fragrance, perfume, cosmetics, aromatherapy, and spa sectors. Beyond its aesthetic and sensory applications, this plant offers medicinal benefits as a natural herbal remedy and finds use in household cleaning products. While extensive genomic data, inclusive of plastid and nuclear genomes, are available for this species, researchers have yet to characterize its mitochondrial genome. This gap in knowledge hampers deeper understanding of the genome organization and its evolutionary significance.ResultsThrough the course of this study, we successfully assembled and annotated the mitochondrial genome of L. angustifolia, marking a first in this domain. This assembled genome encompasses 61 genes, which comprise 34 protein-coding genes, 24 transfer RNA genes, and three ribosomal RNA genes. We identified a chloroplast sequence insertion into the mitogenome, which spans a length of 10,645 bp, accounting for 2.94% of the mitogenome size. Within these inserted sequences, there are seven intact tRNA genes (trnH-GUG, trnW-CCA, trnD-GUC, trnS-GGA, trnN-GUU, trnT-GGU, trnP-UGG) and four complete protein-coding genes (psbA, rps15, petL, petG) of chloroplast derivation. Additional discoveries include 88 microsatellites, 15 tandem repeats, 74 palindromic repeats, and 87 forward long repeats. An RNA editing analysis highlighted an elevated count of editing sites in the cytochrome c oxidase genes, notably ccmB with 34 editing sites, ccmFN with 32, and ccmC with 29. All protein-coding genes showed evidence of cytidine-to-uracil conversion. A phylogenetic analysis, utilizing common protein-coding genes from 23 Lamiales species, yielded a tree with consistent topology, supported by high confidence values.ConclusionsAnalysis of the current mitogenome resource revealed its typical circular genome structure. Notably, sequences originally from the chloroplast genome were found within the mitogenome, pointing to the occurrence of horizontal gene transfer between organelles. This assembled mitogenome stands as a valuable resource for subsequent studies on mitogenome structures, their evolution, and molecular biology.