Post-transcriptional Regulation Research Articles

Epitranscriptome insights into Riccia fluitans L. (Marchantiophyta) aquatic transition using nanopore direct RNA sequencing

BackgroundRiccia fluitans, an amphibious liverwort, exhibits a fascinating adaptation mechanism to transition between terrestrial and aquatic environments. Utilizing nanopore direct RNA sequencing, we try to capture the complex epitranscriptomic changes undergone in response to land-water transition.ResultsA significant finding is the identification of 45 differentially expressed genes (DEGs), with a split of 33 downregulated in terrestrial forms and 12 upregulated in aquatic forms, indicating a robust transcriptional response to environmental changes. Analysis of N6-methyladenosine (m6A) modifications revealed 173 m6A sites in aquatic and only 27 sites in the terrestrial forms, indicating a significant increase in methylation in the former, which could facilitate rapid adaptation to changing environments. The aquatic form showed a global elongation bias in poly(A) tails, which is associated with increased mRNA stability and efficient translation, enhancing the plant’s resilience to water stress. Significant differences in polyadenylation signals were observed between the two forms, with nine transcripts showing notable changes in tail length, suggesting an adaptive mechanism to modulate mRNA stability and translational efficiency in response to environmental conditions. This differential methylation and polyadenylation underline a sophisticated layer of post-transcriptional regulation, enabling Riccia fluitans to fine-tune gene expression in response to its living conditions.ConclusionsThese insights into transcriptome dynamics offer a deeper understanding of plant adaptation strategies at the molecular level, contributing to the broader knowledge of plant biology and evolution. These findings underscore the sophisticated post-transcriptional regulatory strategies Riccia fluitans employs to navigate the challenges of aquatic versus terrestrial living, highlighting the plant’s dynamic adaptation to environmental stresses and its utility as a model for studying adaptation mechanisms in amphibious plants.

SNPs in microRNA seed region and impact of miR-375 in concurrent regulation of multiple lipid accumulation-related genes

Bovine intramuscular fat (IMF), commonly referred to as marbling, is regulated by lipid metabolism, which includes adipogenesis, lipogenesis, glycerolipid synthesis, and lipolysis. In recent years, breeding researchers have identified single nucleotide polymorphisms (SNPs) as useful marker-assisted selection tools for improving marbling scores in national breeding programs. These included causal SNPs that induce phenotypic variation. MicroRNAs (miRNAs) are small highly conserved non-coding RNA molecules that bind to multiple non-coding regions. They are involved in post-transcriptional regulation. Multiple miRNAs may regulate a given target. Previously, three SNPs in the GPAM 3ʹ UTR and four miRNAs were identified through in silico assays. The aim of this study is to verify the binding ability of the four miRNAs to the SNPs within the 3ʹUTR of GPAM, and to identify the regulatory function of miR-375 in the expression of genes related to lipid metabolism in mammalian adipocytes. It was verified that the four miRNAs bind to the GPAM 3ʹUTR, and identified that the miR-375 sequence is highly conserved. Furthermore, it was founded that miR-375 upregulated the GPAM gene, C/EBPα, PPARγ and lipid metabolism-related genes and promoted lipid droplet accumulation in 3T3-L1 cells. In conclusion, these results suggest that miR-375 is a multifunctional regulator of multiple lipid metabolism-related genes and may aid in obesity research as a biomarker.

Transcriptome analysis reveals the role of Long noncoding RNAs (lncRNA) in specific deposition of inosine monphosphate in Jingyuan chickens.

Inosine monphosphate (IMP) is one of the important indicators for evaluating meat flavor, and long noncoding RNAs (lncRNAs) play an important role in its transcription and post-transcriptional regulation. Currently, there is little information about how lncRNA regulates the specific deposition of IMP in chicken muscle. In this study, we used transcriptome sequencing to analyze the lncRNAs of the breast and leg muscles of the Jingyuan chicken and identified a total of 357 differentially expressed lncRNAs (DELs), of which 158 were up-regulated and 199 were down-regulated. There were 2,203 and 7,377 cis- and trans-regulated target genes of lncRNAs, respectively, and we identified the lncRNA target genes that are involved in NEGF signaling pathway, glycolysis/ glucoseogenesis and biosynthesis of amino acids pathways. Meanwhile, 621 pairs of lncRNA-miRNA-mRNA interaction networks were constructed with target genes involved in purine metabolism, fatty acid metabolism, and biosynthesis of amino acids. Next, three interacting meso-networks gga-miR-1603-LNC_000324-PGM1, gga-miR-1768-LNC_000324-PGM1 and gga-miR-21-LNC_011339- AMPD1 were identified as closely associated with IMP-specific deposition. Both differentially expressed genes (DEGs) PGM1 and AMPD1 were significantly enriched in IMP synthesis and metabolism-related pathways, and participated in the anabolic process of IMP in the form of organic matter synthesis and energy metabolism. This study obtained lncRNAs and target genes affecting IMP-specific deposition in Jingyuan chickens based on transcriptome analysis, which deepened our insight into the role for lncRNAs in chicken meat quality.

Plasmid targeting and destruction by the DdmDE bacterial defence system.

While eukaryotic Argonautes play a pivotal role in post-transcriptional gene regulation through nucleic acid cleavage, some short prokaryotic Argonaute variants (pAgos) rely on auxiliary nuclease factors for efficient foreign DNA degradation (1). Here, we elucidate the activation pathway of the DNA Defense Module DdmDE system, which rapidly eliminates small, multicopy plasmids from Vibrio cholerae Seventh Pandemic Strain (7PET) (2). Through a combination of cryo-EM, biochemistry and in vivo plasmid clearance assays, we demonstrate DdmE is a catalytically inactive, DNA-guided, DNA-targeting pAgo with a distinctive insertion domain. We observe that DdmD transitions from an autoinhibited, dimeric protein to monomers upon loading of single-stranded DNA targets. Furthermore, the complete structure of the DdmDE-guide-target handover complex provides a comprehensive view into how DNA recognition triggers processive plasmid destruction. Our work establishes a mechanistic foundation for how pAgo utilize ancillary factors to achieve plasmid clearance, and provides insights into anti-plasmid immunity in bacteria.

Identification of microRNAs in black tiger shrimp (Penaeus monodon) under acute low-salinity stress

Salinity is a common abiotic stress in the culture of penaeid shrimp. Through post-transcriptional regulation of gene transcripts, microRNAs (miRNAs) play an important role in the adaptation to a stressful environment. However, the involvement of miRNAs in the salinity stress response of shrimp remains unclear. In the present study, the sequence and expression profile of miRNAs in the hepatopancreas of low-salinity-treated Penaeus monodon were obtained by the high-throughput sequencing technique. A total of 679 miRNAs were identified, including 167 miRNAs that were significantly differentially expressed after low-salinity exposure (p < 0.05). Remarkably, most of these miRNAs were downregulated, suggesting that a series of genes were activated to participate in stress response. In addition, 43 miRNAs differentially expressed at all treatment were selected as putative key modulators. Enrichment analysis of genes targeted by these miRNAs indicated that a network that consists of the nervous system, the immune system, and the endocrine system played a crucial role in maintaining the homeostasis of P. monodon under low-salinity stress. These findings may help contribute to a better understanding of the mechanism that regulates salinity tolerance in shrimp and provide valuable genetic information for subsequent studies.

Comprehensive analysis of competing endogenous RNA networks involved in the regulation of glycolysis in clear cell renal cell carcinoma

Abstract Objectives This study aims to elucidate the role of competing endogenous RNAs (ceRNAs), which are pivotal in the post-transcriptional regulation of cancer cells, in the glycolysis of clear cell renal cell carcinoma (ccRCC). Methods RNA-seq data from ccRCC samples and public datasets were subjected to differential expression analysis to identify the upregulated circular RNAs (circRNAs), long noncoding RNAs (lncRNAs), and mRNAs for constructing a ceRNA network. This network focused on the upregulated mRNAs linked to glycolysis and gluconeogenesis, which were verified at the proteome level using the CPTAC database. The ENCORI database was used to predict the lncRNA/circRNA-miRNA and miRNA-mRNA interactions, which formed a network visualized using Cytoscape. This study further examined the association of selected lncRNAs/circRNAs with biological processes and patient survival and explored lncRNA and mRNA expressions at the single-cell level. Results Three circRNAs and eight lncRNAs were identified to be regulators of four glycolysis pathway genes (HK2, LDHA, PFKP, and ALDOC) via 54 miRNAs. Notably, their expressions were aberrant at the transcriptome and proteome levels. These RNA elements were correlated with malignant and immune pathways, and several lncRNAs showed prognostic significance for ccRCC. Furthermore, single-cell RNA sequencing indicated the abnormal enrichment of these lncRNAs and mRNAs in malignant cells. Conclusions This study identified a ceRNA network that plays a critical role in the glycolysis of ccRCC. These findings highlight the importance of ceRNAs in cancer malignancy and their potential impact on patient prognosis.

Prediction of Age-Related MicroRNA Signature in Mesenchymal Stem Cells by using Computational Methods.

Aging is a phenomenon which occurs over time and leads to the decay of living organisms. During the progression of aging, some age-associated diseases including cardiovascular disease, cancers, and neurological, mental, and physical disorders could develop. Genetic and epigenetic factors like microRNAs, as one of the post-transcriptional regulators of genes, play important roles in senescence. The self-renewal and differentiation capacity of mesenchymal stem cells makes them good candidates for regenerative medicine. The objective of this study is to evaluate senescence-related miRNAs in human MSCs using bioinformatics analysis. In this study, the Gene Expression Omnibus (GEO) database was used to investigate the senescence-related genome profile. Then, down-regulated genes were selected for further bioinformatics analysis with the assumption that their decreased expression is associated with an increased aging process. Considering that miRNAs can interfere in gene expression, miRNAs complementary to these genes were identified using bioinformatics software. Through bioinformatics analysis, we predicted hsa-miR-590-3p, hsa-miR-10b-3p, hsamiR- 548 family, hsa-miR-144-3p, and hsa-miR-30b-5p which involve in cellular senescence and the aging of human MSCs. miRNA mimics or anti-miRNA agents have the potential to be used as anti-aging tools for MSCs.

Nuclear genomes of dinoflagellates reveal evolutionarily conserved pattern of RNA editing relative to stress response

Dinoflagellates are a group of diverse protists with complex genomes whose gene expression regulation mechanisms remain little known. RNA editing is a post-transcriptional regulatory mechanism of gene expression utilized by diverse species, and has been described primarily in the plastid and mitochondrial genomes of dinoflagellates. Its role in post-transcriptional regulation in the nuclear genomes of dinoflagellates remains largely unexplored. Here, integrating genome and transcriptome data from two dinoflagellate taxa in a comparative analysis, we identified 10,486 and 69,953 putative RNA editing sites in the nuclear genomes of the coral symbiont, Durusdinium trenchii CCMP2556 and the free-living bloom-forming taxon, Prorocentrum cordatum CCMP1329. We recovered all 12 possible types of RNA edits, with more edits representing transitions than transversions. In contrast to other eukaryotes, we found a dominance of A-to-T transversion in non-coding regions, many of which were condition-specific. Overall, the RNA editing sites implicate 7.5% of D. trenchii genes and 13.2% of P. cordatum genes. Some sites (1.5% in D. trenchii and more-substantially 62.3% in P. cordatum) were edited at significantly different frequencies in distinct growth conditions. The distribution of editing types and locations exhibited conserved patterns between the two phylogenetically distant species. Interestingly, A-to-T editing within the untranslated regions appear to be associated with upregulation of the edited genes in response to heat stress. These results lend support to the hypothesis that RNA editing is a key molecular mechanism that underpins regulation of gene expression in dinoflagellates.

Exploring miRNA-target modules in Paeonia lactiflora stamen petalization through integrated miRNAome, transcriptome, and degradome analysis

Variation in floral organ number in plants is triggered by extremely complex transcriptional and post-transcriptional regulatory processes. MicroRNAs (miRNAs) play a pivotal role in the post-transcriptional regulation of floral organs. Paeonia lactiflora Pall., originating from China, is a precious herbaceous plant with ornamental, medicinal, and oil properties. Building on previous transcriptional studies, this work examined post-transcriptional regulation of peony stamen petalization using critical-stage flower buds. Using high-throughput small RNA sequencing, a miRNA expression profile was constructed. This was used to identify 10 known, 334 conserved, and 255 novel miRNAs, 155, 151, and 44 of which were differentially expressed at three developmental stages (stamen primordium, stamen primordium partly petaloid, and stamen primordium completely petaloid). Degradome analysis identified 55 miRNAs and 127 potential target genes. A miRNA-target network suggested that miR172-PlRAP2, miR160-PlARF, miR396-PlGRF, miR319-PlTCP4, and miR384\\394-PlFBOX modules are key regulators of peony stamen petalization. The regulation of miR319 and PlTCP4 during peony flower development was validated through transient expression in tobacco. This study provides insight into miRNA-mediated regulation of petalized stamen formation in herbaceous peony and refines the post-transcriptional network at critical stages of this process.

MicroRNA-26a in respiratory diseases: mechanisms and therapeutic potential.

MicroRNAs (miRNAs) are short, non-coding single-stranded RNA moleculesapproximately 22 nucleotides in length, intricately involved in post-transcriptional gene expression regulation. Over recent years, researchers have focused keenly on miRNAs, delving into their mechanisms in various diseases such as cancers. Among these, miR-26a emerges as a pivotal player in respiratory ailments such as pneumonia, idiopathic pulmonary fibrosis, lung cancer, asthma, and chronic obstructive pulmonary disease. Studies have underscored the significance of miR-26a in the pathogenesis and progression of respiratory diseases, positioning it as a promising therapeutic target. Nevertheless, several challenges persist in devising medical strategies for clinical trials involving miR-26a. In this review, we summarize the regulatory role and significance of miR-26a in respiratory diseases, and we analyze and elucidate the challenges related to miR-26a druggability, encompassing issues such as the efficiency of miR-26a, delivery, RNA modification, off-target effects, and the envisioned therapeutic potential of miR-26a in clinical settings.

Genetic Screening Revealed the Negative Regulation of miR-310~313 Cluster Members on Imd Pathway during Gram-Negative Bacterial Infection in Drosophila

Innate immune response is the first line of host defense against pathogenic microorganisms, and its excessive or insufficient activation is detrimental to the organism. Many individual microRNAs (miRNAs) have emerged as crucial post-transcriptional regulators of immune homeostasis in Drosophila melanogaster. However, the synergistical regulation of miRNAs located within a cluster on the Imd-immune pathway remains obscured. In our study, a genetic screening with 52 transgenic UAS-miRNAs was performed to identify ten miRNAs or miRNA clusters, including the miR310~313 cluster, which may function on Imd-dependent immune responses. The miRNA RT-qPCR analysis showed that the expression of miR-310~313 cluster members exhibited an increase at 6–12 h post E. Coli infection. Furthermore, the overexpression of the miR-310~313 cluster impaired the Drosophila survival. And the overexpression of miR-310/311/312 reduced Dpt expression, an indication of Imd pathway induced by Gram-negative bacteria. Conversely, the knockdown of miR-310/311/312 led to increases in Dpt expression. The Luciferase reporter expression assays and RT-qPCR analysis confirmed that miR-310~313 cluster members directly co-targeted and inhibited Imd transcription. These findings reveal that the members of the miR-310~313 cluster synergistically inhibit Imd-dependent immune responses by co-targeting the Imd gene in Drosophila.

Regulatory microRNAs and phasiRNAs of paclitaxel biosynthesis in Taxus chinensis

Paclitaxel (trade name Taxol) is a rare diterpenoid with anticancer activity isolated from Taxus. At present, paclitaxel is mainly produced by the semi-synthetic method using extract of Taxus tissues as raw materials. The studies of regulatory mechanisms in paclitaxel biosynthesis would promote the production of paclitaxel through tissue/cell culture approaches. Here, we systematically identified 990 transcription factors (TFs), 460 microRNAs (miRNAs), and 160 phased small interfering RNAs (phasiRNAs) in Taxus chinensis to explore their interactions and potential roles in regulation of paclitaxel synthesis. The expression levels of enzyme genes in cone and root were higher than those in leaf and bark. Nearly all enzyme genes in the paclitaxel synthesis pathway were significantly up-regulated after jasmonate treatment, except for GGPPS and CoA Ligase. The expression level of enzyme genes located in the latter steps of the synthesis pathway was significantly higher in female barks than in male. Regulatory TFs were inferred through co-expression network analysis, resulting in the identification of TFs from diverse families including MYB and AP2. Genes with ADP binding and copper ion binding functions were overrepresented in targets of miRNA genes. The miRNA targets were mainly enriched with genes in plant hormone signal transduction, mRNA surveillance pathway, cell cycle and DNA replication. Genes in oxidoreductase activity, protein-disulfide reductase activity were enriched in targets of phasiRNAs. Regulatory networks were further constructed including components of enzyme genes, TFs, miRNAs, and phasiRNAs. The hierarchical regulation of paclitaxel production by miRNAs and phasiRNAs indicates a robust regulation at post-transcriptional level. Our study on transcriptional and posttranscriptional regulation of paclitaxel synthesis provides clues for enhancing paclitaxel production using synthetic biology technology.

SRNA expression profile of KPC-2-producing carbapenem-resistant Klebsiella pneumoniae: Functional role of sRNA51.

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has significant challenges to human health and clinical treatment, with KPC-2-producing CRKP being the predominant epidemic strain. Therefore, there is an urgent need to identify new therapeutic targets and strategies. Non-coding small RNA (sRNA) is a post-transcriptional regulator of genes involved in important biological processes in bacteria and represents an emerging therapeutic strategy for antibiotic-resistant bacteria. In this study, we analyzed the transcription profile of KPC-2-producing CRKP using RNA-seq. Of the 4693 known genes detected, the expression of 307 genes was significantly different from that of carbapenem-sensitive Klebsiella pneumoniae (CSKP), including 133 up-regulated and 174 down-regulated genes. Both the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and Gene Ontology (GO) analysis showed that these differentially expressed genes (DEGs) were mainly related to metabolism. In addition, we identified the sRNA expression profile of KPC-2-producing CRKP for the first time and detected 115 sRNAs, including 112 newly discovered sRNAs. Compared to CSKP, 43 sRNAs were differentially expressed in KPC-2-producing CRKP, including 39 up-regulated and 4 down-regulated sRNAs. We chose sRNA51, the most significantly differentially expressed sRNA in KPC-2-producing CRKP, as our research subject. By constructing sRNA51-overexpressing KPC-2-producing CRKP strains, we found that sRNA51 overexpression down-regulated the expression of acrA and alleviated resistance to meropenem and ertapenem in KPC-2-producing CRKP, while overexpression of acrA in sRNA51-overexpressing strains restored the reduction of resistance. Therefore, we speculated that sRNA51 could affect the resistance of KPC-2-producing CRKP by inhibiting acrA expression and affecting the formation of efflux pumps. This provides a new approach for developing antibiotic adjuvants to restore the sensitivity of CRKP.

Disentangling genetic effects on transcriptional and post-transcriptional gene regulation through integrating exon and intron expression QTLs

Expression quantitative trait loci (eQTL) studies typically consider exon expression of genes and discard intronic RNA sequencing reads despite their information on RNA metabolism. Here, we quantify genetic effects on exon and intron levels of genes and their ratio in lymphoblastoid cell lines, revealing thousands of cis-QTLs of each type. While genetic effects are often shared between cis-QTL types, 7814 (47%) are not detected as top cis-QTLs at exon levels. We show that exon levels preferentially capture genetic effects on transcriptional regulation, while exon-intron-ratios better detect those on co- and post-transcriptional processes. Considering all cis-QTL types substantially increases (by 71%) the number of colocalizing variants identified by genome-wide association studies (GWAS). It further allows dissecting the potential gene regulatory processes underlying GWAS associations, suggesting comparable contributions by transcriptional (50%) and co- and post-transcriptional regulation (46%) to complex traits. Overall, integrating intronic RNA sequencing reads in eQTL studies expands our understanding of genetic effects on gene regulatory processes.

Regulatory roles of miRNA-530 in the post-transcriptional regulation of NF-κB signaling pathway through targeted modulation of IκBα in Sebastesschlegelii

MicroRNAs (miRNAs) are a crucial type of non-coding RNAs involved in post-transcriptional regulation. The playing essential regulatory roles in the NF-κB signaling pathway and modulate the host immune response to diverse pathogens by targeting IκBα. However, the regulatory mechanism of miRNAs in relation with IκBα in Sebastes schlegelii remains unclear. In our study, we identified two copies of IkBα gene in black rockfish (Sebastes schlegelii), namely IkBα1 and IkBα2. Moreover, we have discovered that miRNA-530 can activate the NF-κB signaling pathway by inhibiting the expression of IκBα, thereby inducing the inflammatory response. This project comprehensively investigated the interactive regulatory roles of miRNA-530 in the NF-κB signaling pathway at both cellular and in vivo levels, while also elucidating the regulatory relationships between miRNA-530 and IκBα. In conclusion, our research confirmed that miRNA-530 can target the 3′UTR region of IκBα, resulting in a decrease in the expression of IκBα at the post-transcriptional level and inhibiting its translation. The findings contribute to the understanding of the regulatory network of non-coding RNA in teleosts and its subsequent regulation of the NF-κB signaling pathway by miRNAs.

MRNA-CLA: An interpretable deep learning approach for predicting mRNA subcellular localization

Messenger RNA (mRNA) is vital for post-transcriptional gene regulation, acting as the direct template for protein synthesis. However, the methods available for predicting mRNA subcellular localization need to be improved and enhanced. Notably, few existing algorithms can annotate mRNA sequences with multiple localizations. In this work, we propose the mRNA-CLA, an innovative multi-label subcellular localization prediction framework for mRNA, leveraging a deep learning approach with a multi-head self-attention mechanism. The framework employs a multi-scale convolutional layer to extract sequence features across different regions and uses a self-attention mechanism explicitly designed for each sequence. Paired with Position Weight Matrices (PWMs) derived from the convolutional neural network layers, our model offers interpretability in the analysis. In particular, we perform a base-level analysis of mRNA sequences from diverse subcellular localizations to determine the nucleotide specificity corresponding to each site. Our evaluations demonstrate that the mRNA-CLA model substantially outperforms existing methods and tools.

The DEAD-box RNA helicase PfDOZI imposes opposing actions on RNA metabolism in Plasmodium falciparum

In malaria parasites, the regulation of mRNA translation, storage and degradation during development and life-stage transitions remains largely unknown. Here, we functionally characterized the DEAD-box RNA helicase PfDOZI in P. falciparum. Disruption of pfdozi enhanced asexual proliferation but reduced sexual commitment and impaired gametocyte development. By quantitative transcriptomics, we show that PfDOZI is involved in the regulation of invasion-related genes and sexual stage-specific genes during different developmental stages. PfDOZI predominantly participates in processing body-like mRNPs in schizonts but germ cell granule-like mRNPs in gametocytes to impose opposing actions of degradation and protection on different mRNA targets. We further show the formation of stress granule-like mRNPs during nutritional deprivation, highlighting an essential role of PfDOZI-associated mRNPs in stress response. We demonstrate that PfDOZI participates in distinct mRNPs to maintain mRNA homeostasis in response to life-stage transition and environmental changes by differentially executing post-transcriptional regulation on the target mRNAs.

Post-transcriptional regulation and subcellular localization of G-protein γ7 subunit: implications for striatal function and behavioral responses to cocaine

The striatal D1 dopamine receptor (D1R) and A2a adenosine receptor (A2aR) signaling pathways play important roles in drug-related behaviors. These receptors activate the Golf protein comprised of a specific combination of αolfβ2γ7 subunits. During assembly, the γ7 subunit sets the cellular level of the Golf protein. In turn, the amount of Golf protein determines the collective output from both D1R and A2aR signaling pathways. This study shows the Gng7 gene encodes multiple γ7 transcripts differing only in their non-coding regions. In striatum, Transcript 1 is the predominant isoform. Preferentially expressed in the neuropil, Transcript 1 is localized in dendrites where it undergoes post-transcriptional regulation mediated by regulatory elements in its 3′ untranslated region that contribute to translational suppression of the γ7 protein. Earlier studies on gene-targeted mice demonstrated loss of γ7 protein disrupts assembly of the Golf protein. In the current study, morphological analysis reveals the loss of the Golf protein is associated with altered dendritic morphology of medium spiny neurons. Finally, behavioral analysis of conditional knockout mice with cell-specific deletion of the γ7 protein in distinct populations of medium spiny neurons reveals differential roles of the Golf protein in mediating behavioral responses to cocaine. Altogether, these findings provide a better understanding of the regulation of γ7 protein expression, its impact on Golf function, and point to a new potential target and mechanisms for treating addiction and related disorders.

MLm5C: A high-precision human RNA 5-methylcytosine sites predictor based on a combination of hybrid machine learning models

RNA modification serves as a pivotal component in numerous biological processes. Among the prevalent modifications, 5-methylcytosine (m5C) significantly influences mRNA export, translation efficiency and cell differentiation and are also associated with human diseases, including Alzheimer’s disease, autoimmune disease, cancer, and cardiovascular diseases. Identification of m5C is critically responsible for understanding the RNA modification mechanisms and the epigenetic regulation of associated diseases. However, the large-scale experimental identification of m5C present significant challenges due to labor intensity and time requirements. Several computational tools, using machine learning, have been developed to supplement experimental methods, but identifying these sites lack accuracy and efficiency. In this study, we introduce a new predictor, MLm5C, for precise prediction of m5C sites using sequence data. Briefly, we evaluated eleven RNA sequence-derived features with four basic machine learning algorithms to generate baseline models. From these 44 models, we ranked them based on their performance and subsequently stacked the Top 20 baseline models as the best model, named MLm5C. The MLm5C outperformed the-state-of-the-art predictors. Notably, the optimization of the sequence length surrounding the modification sites significantly improved the prediction performance. MLm5C is an invaluable tool in accelerating the detection of m5C sites within the human genome, thereby facilitating in the characterization of their roles in post-transcriptional regulation.

1H, 13C, and 15N resonance assignments of the La Motif of the human La-related protein 1.

Human La-related protein 1 (HsLARP1) is involved in post-transcriptional regulation of certain 5'terminal oligopyrimidine (5'TOP) mRNAs as well as other mRNAs and binds to both the 5'TOP motif and the 3'-poly(A) tail of certain mRNAs. HsLARP1 is heavily involved in cell proliferation, cell cycle defects, and cancer, where HsLARP1 is significantly upregulated in malignant cells and tissues. Like all LARPs, HsLARP1 contains a folded RNA binding domain, the La motif (LaM). Our current understanding of post-transcriptional regulation that emanates from the intricate molecular framework of HsLARP1 is currently limited to small snapshots, obfuscating our understanding of the full picture on HsLARP1 functionality in post-transcriptional events. Here, we present the nearly complete resonance assignment of the LaM of HsLARP1, providing a significant platform for future NMR spectroscopic studies.