Hidden codes in mRNA: Control of gene expression by m6A.

Information in mRNA has largely been thought to be confined to its nucleotide sequence. However, the advent of mapping techniques to detect modified nucleotides has revealed that mRNA contains additional information in the form of chemical modifications. The most abundant modified nucleotide is N6-methyladenosine (m6A), a methyl modification of adenosine. Although early studies viewed m6A as a dynamic and tissue-specific modification, it is now clear that the mRNAs that contain m6A and the location of m6A in those transcripts are largely universal and are influenced by gene architecture, i.e., the size and location of exons and introns. m6A can affect nuclear processes such as splicing and epigenetic regulation, but the major effect of m6A on mRNAs is to promote degradation in the cytoplasm. m6A marks a functionally related cohort of mRNAs linked to certain biological processes, including cell differentiation and cell fate determination. m6A is also enriched in other cohorts of mRNAs and can therefore affect their respective cellular processes and pathways. Future work will focus on understanding how the m6A pathway is regulated to achieve control of m6A-containing mRNAs.

Zc3h13 Regulates Nuclear RNA m6A Methylation and Mouse Embryonic Stem Cell Self-Renewal.

N6-methyladenosine (m6A) is an abundant modification in eukaryotic mRNA, regulating mRNA dynamics by influencing mRNA stability, splicing, export, and translation. However, the precise m6A regulating machinery still remains incompletely understood. Here we demonstrate that ZC3H13, a zinc-finger protein, plays an important role in modulating RNA m6A methylation in the nucleus. We show that knockdown of Zc3h13 in mouse embryonic stem cell significantly decreases global m6A level on mRNA. Upon Zc3h13 knockdown, a great majority of WTAP, Virilizer, and Hakai translocate to the cytoplasm, suggesting that Zc3h13 is required for nuclear localization of the Zc3h13-WTAP-Virilizer-Hakai complex, which is important for RNA m6A methylation. Finally, Zc3h13 depletion, as does WTAP, Virilizer, or Hakai, impairs self-renewal and triggers mESC differentiation. Taken together, our findings demonstrate that Zc3h13 plays a critical role in anchoring WTAP, Virilizer, and Hakai in the nucleus to facilitate m6A methylation and to regulate mESC self-renewal.

Zc3h13/Flacc is required for adenosine methylation by bridging the mRNA-binding factor Rbm15/Spenito to the m6A machinery component Wtap/Fl(2)d.

N6-methyladenosine (m6A) is the most abundant mRNA modification in eukaryotes, playing crucial roles in multiple biological processes. m6A is catalyzed by the activity of methyltransferase-like 3 (Mettl3), which depends on additional proteins whose precise functions remain poorly understood. Here we identified Zc3h13 (zinc finger CCCH domain-containing protein 13)/Flacc [Fl(2)d-associated complex component] as a novel interactor of m6A methyltransferase complex components in Drosophila and mice. Like other components of this complex, Flacc controls m6A levels and is involved in sex determination in Drosophila We demonstrate that Flacc promotes m6A deposition by bridging Fl(2)d to the mRNA-binding factor Nito. Altogether, our work advances the molecular understanding of conservation and regulation of the m6A machinery.

m6A methyltransferase ZC3H13 improves pulmonary fibrosis in mice through regulating Bax expression.

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease. N6-methyladenosine (m6A) is a reversible RNA modification that was shown to be associated with IPF development. The present study aimed to explore the function and potential mechanism of the m6A methylation enzyme zinc finger CCCH-type containing 13 (ZC3H13) in IPF. In the study, bioinformatic screening yielded a differentially expressed m6A gene, ZC3H13, which was down-regulated in GEO microarrays, BLM-induced mouse models, and cellular models. Overexpression of ZC3H13 reduced histopathological damage of lung tissues in mice, mitigated fibrosis (including reduced α-SMA, collagen Ⅰ, and Vimentin levels, and elevated E-cadherin levels), decreased lung/body weight ratio and lung hydroxyproline levels, reduced oxidative stress (increased SOD activity and GSH-Px activity and decreased MDA levels), suppressed apoptosis within lung tissues and MLE-12 cells, promoted Bcl-2 expression, and inhibited Bax expression. Bax expression was found to be negatively correlated with ZC3H13 expression by correlation analysis. ZC3H13 could bind Bax mRNA and promote its m6A methylation through reading protein YTHDC1, thereby inhibiting its stability. Bax inhibition ameliorated BLM-induced MLE-12 cell dysfunction and partially abrogated the inhibition of MLE-12 cell function by ZC3H13 downregulation. In conclusion, m6A methyltransferase ZC3H13 impedes lung epithelial cell apoptosis and thus improves pulmonary fibrosis by promoting Bax mRNA m6A methylation and down-regulating Bax expression through reading protein YTHDC1.

ZC3H13 Accelerates Keloid Formation by Mediating N6-methyladenosine Modification of HIPK2.

Keloids are fibroproliferative skin disorders caused by the improper healing of wounded skin. A growing body of evidence suggests the involvement of N6-Methyladenosine (m6A) modification in various bioprocesses; however, its role in keloid formation has not yet been investigated. The aim of this study was to determine the effect of the m6A regulator zinc finger CCCH domain containing protein 13 (ZC3H13) on the pathogenesis of keloid formation. ZC3H13 and homeodomain-interacting protein kinase 2 (HIPK2) expression was evaluated in healthy skin and keloid tissues, as well as in human dermal fibroblasts and human keloid fibroblasts (HKF), using qRT-PCR and western blotting. The effects of ZC3H13 overexpression and knockdown on the cell function of HKFs were assessed using CCK8, transwell, and flow cytometry. Furthermore, the influence of ZC3H13 on HIPK2 m6A modification was assessed using MeRIP-qPCR and mRNA stability assays. Both ZC3H13 expression and m6A RNA methylation were upregulated in keloid tissues and HKFs. Silencing of ZC3H13 inhibited proliferation and migration, while enhancing apoptosis in HKFs, whereas overexpression had the opposite effect. Furthermore, HIPK2 levels were high in keloid tissues and HKFs, and a positive correlation was observed between ZC3H13 and HIPK2. In HKFs, ZC3H13 overexpression elevated the m6A levels of HIPK2 mRNA and reduced the rate of HIPK2 mRNA degradation. Mechanically, ZC3H13-induced m6A modifications significantly improved HIPK2 mRNA stability. Collectively, ZC3H13 accelerated keloid formation by mediating the m6A modification of HIPK2 mRNA and maintaining its stability.

Overexpressed ZC3H13 suppresses papillary thyroid carcinoma growth through m6A modification-mediated IQGAP1 degradation.

PURPOSE: The purpose of this study was to clarify the effect of ZC3H13 on the growth of papillary thyroid carcinoma (PTC). METHODS: Firstly, we used qRT-PCR and Western blot to compare the difference in the expression of ZC3H13 between normal thyroid epithelial cells and PTC cell lines. Then, ZC3H13 overexpression/knockout thyroid cancer cells were constructed by lentivirus transfection, and the effects of overexpression of ZC3H13 on the proliferation, migration and invasion of PTC cells were detected by CCK8 and transwell experiments. Lastly, MeRIP-qPCR, RIP and o Actinomycin D were used to verify that ZC3H13 regulated the expression of downstream target gene IQGAP1 through m6A modification. RESULTS: ZC3H13 expression was decreased in PTC cell lines BCPAP, KTC-1, k1, HTH83, and TPC-1. Proliferation, invasion, and migration of PTC cells were inhibited by overexpressed ZC3H13 but increased by knockdown of ZC3H13. IQGAP1 expression was suppressed by ZC3H13 overexpression but enhanced by ZC3H13 knockdown. In ZC3H13-overexpressed PTC cells, the m6A level of IQGAP1 mRNA was increased, and the IQGAP1 mRNA expression was decreased with the increasing time of Actinomycin D treatment. YTHDF2 enriched more IQGAP1 mRNA than IgG and knockdown of YTHDF2 reversed the effect of ZC3H13 overexpression on IQGAP1 mRNA stability. The xenograft tumor experiment in nude mice confirmed that the overexpression of ZC3H13 inhibited tumor growth, while overexpression of IQGAP1 could reverse the inhibitory effect of ZC3H13 overexpression on tumor growth. CONCLUSION: ZC3H13 mediates IQGAP1 mRNA degradation by promoting m6A modification of IQGAP1 mRNA, this provides a prospective therapeutic target for PTC.

Genetic associations with age at dementia onset in the PSEN1 E280A Colombian kindred.

INTRODUCTION: Genetic associations with Alzheimer's disease (AD) age at onset (AAO) could reveal genetic variants with therapeutic applications. We present a large Colombian kindred with autosomal dominant AD (ADAD) as a unique opportunity to discover AAO genetic associations. METHODS: A genetic association study was conducted to examine ADAD AAO in 340 individuals with the PSEN1 E280A mutation via TOPMed array imputation. Replication was assessed in two ADAD cohorts, one sporadic early-onset AD study and four late-onset AD studies. RESULTS: 13 variants had p<1×10-7 or p<1×10-5 with replication including three independent loci with candidate associations with clusterin including near CLU. Other suggestive associations were identified in or near HS3ST1, HSPG2, ACE, LRP1B, TSPAN10, and TSPAN14. DISCUSSION: Variants with suggestive associations with AAO were associated with biological processes including clusterin, heparin sulfate, and amyloid processing. The detection of these effects in the presence of a strong mutation for ADAD reinforces their potentially impactful role.

Gene signatures, immune infiltration, and drug sensitivity based on a comprehensive analysis of m6a RNA methylation regulators in cervical cancer.

BACKGROUND: Cervical cancer is the fourth most common cancer in women. N6-dimethyladenosine (m6A) mRNA methylation is closely associated with cervical cancer. METHODS: Using TCGA database, we studied the expression and mutation of m6A-related genes in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) and obtained genetic characteristics based on an m6A risk model and prognostic value of m6A. We studied the effects of the m6A risk score on immune features and genomic changes of patients with CESC, evaluated the sensitivity of patients with CESC to different small-molecule drugs based on the m6A risk score, and established a clinical prediction model. RESULTS: Ten m6A-related genes were differentially expressed between CESC and normal tissues. High-risk patients had a low overall survival (OS) and significantly low immune scores but showed no significantly altered stromal scores. The tumor mutation burden (TMB) and tumor neoantigen levels significantly differed between the high- and low-risk groups. In the high-risk group, copy number variation (CNV) changes mainly led to gene amplification, while in the low-risk group, CNV changes primarily manifested as gene copy number deletions. ZC3H13 expression was low in CESC tissues. ZC3H13 knockdown promoted CESC cell proliferation, migration, and invasion, reducing the RNA methylation levels. Rapamycin suppressed the CESC cell proliferation, migration, and invasion abilities, increasing the m6A levels. CONCLUSION: m6A mRNA methylation is closely related to the occurrence, development, immune invasion, drug sensitivity, and prognosis of cervical cancer. The prognostic m6A feature model of m6A signature genes can accurately predict the OS of patients with CESC. Drugs targeting factors regulating m6A mRNA methylation might offer a good prospect for treating cervical cancer.

Identification and validation of the N6-methyladenosine RNA methylation regulator ZC3H13 as a novel prognostic marker and potential target for hepatocellular carcinoma.

N6-methyladenosine (m6A) RNA methylation has been implicated in various malignancies. This study aimed to identify prognostic signature based on m6A methylation regulators for hepatocellular carcinoma (HCC) and provide candidate targets for HCC treatment. In this study, the expression levels, prognostic values, correlation with tumor grades and genetic variations of m6A-related genes in HCC were evaluated using bioinformatics analyses. Interestingly, the results show that methyltransferase zinc finger CCCH-type containing 13 (ZC3H13) was expressed at a significantly low level in HCC. Survival outcome analysis suggested that significant correlations existed between ZC3H13 downregulation and poor overall survival (OS) and poor recurrence-free survival (RFS) in HCC patients. Therefore, ZC3H13 was chosen for further experimental validation. The expression of ZC3H13 in HCC cell lines was investigated by western blotting. Knockdown of ZC3H13 significantly enhanced the migration and invasion of HCC cells, as demonstrated by wound healing and transwell assays. Moreover, upregulating ZC3H13 repressed the growth of xenograft tumors in vivo. Functional and pathway enrichment analyses indicated that ZC3H13 might be involved in transcriptional dysregulation or the JAK-STAT signaling pathway in cancer. Additionally, ZC3H13 expression was significantly correlated with lymphocytes and immunomodulators. Therefore, ZC3H13 is a promising candidate as a novel biomarker and therapeutic target for HCC.

ZC3H13 suppresses colorectal cancer proliferation and invasion via inactivating Ras-ERK signaling.

ZC3H13 is a canonical CCCH zinc finger protein, which harbors a somatic frame-shift mutation in colorectal cancer (CRC). However, its expression and biological function were still uncertain. In the current study, we found that ZC3H13 was served as a tumor suppressor in CRC cells, which decreased the expression of Snail, Cyclin D1, and Cyclin E1, and increased the expression of Occludin and Zo-1 through inactivating Ras-ERK signaling pathway. Furthermore, reduction of ZC3H13 associated with advanced TNM stage (p = 0.02), positive regional lymph node metastasis ( p = 0.01). Taken together, the current study indicated that ZC3H13 may be an upstream regulator of Ras-ERK signaling pathway and suppressed invasion and proliferation of CRC.

ZC3H13-Mediated m6A Modification Ameliorates Acute Myocardial Infarction through Preventing Inflammation, Oxidative Stress and Ferroptosis by Targeting lncRNA93358.

BACKGROUND: Acute myocardial infarction (AMI) is a life-threatening event that is associated with RNA modification and programmed cell death (PCD). This study attempted to investigate the impacts of zinc finger CCCH domain-containing protein 13 (ZC3H13)-mediated N6-methyladenosine (m6A) on ferroptosis in AMI. METHODS: The infarcted areas and cardiac function were evaluated, and the expression level of ZC3H13 was measured in AMI rats that were induced by isoproterenol. Meanwhile, oxygen glucose deprivation (OGD) in vitro model was induced to investigate the alterations on inflammation, oxidative stress and ferroptosis. The m6A modification site of lncRNA93358 modified by ZC3H13 was predicted using bioinformatics, and the interaction between ZC3H13 and lncRNA93358 was verified using the dual-luciferase reporter assays. ZC3H13 was overexpressed and lncRNA93358 was silenced to study their regulatory role in cell death, inflammation, oxidative stress and ferroptosis in AMI. RESULTS: Significant decreased expression of ZC3H13 was observed in AMI rats, with impaired cardiac function, enhanced inflammation and oxidative stress. ZC3H13 targeted the modification site GGACC of lncRNA93358 and downregulated lncRNA93358. Silencing lncRNA93358 inhibited cell death, reduced the levels of inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß, suppressed oxidative stress-related indicators (lactate dehydrogenase (LDH), reactive oxygen species (ROS), glutathione (GSH) and malondialdehyde (MDA), as well as downregulated ferroptosis-related acyl-CoA synthetase long chain family member 4 (ACSL4), prostaglandin-endoperoxide synthase 2 (PTGS2) and glutathione peroxidase 4 (GPX4). The effect of silencing lncRNA93358 was further enhanced by overexpression of ZC3H13. CONCLUSION: This study reveals the ZC3H13-mediated epigenetic RNA modification targeting lncRNA93358 and suggests that ZC3H13 overexpression may be a promising approach for AMI treatment.

ZC3H13 may participate in the ferroptosis process of sepsis-induced cardiomyopathy by regulating the expression of Pnn and Rbm25.

BACKGROUND: N6 methyladenosine (m6A) regulates the ferroptosis in different diseases. However, there is no report about the role of the m6A regulator in the ferroptosis process of septic cardiomyopathy (SCM). This study aims to find the potential m6A regulator that participates in the ferroptosis process of SCM. METHODS: Genes related to m6A were identified through bioinformatics analysis in GSE142615. Then, the expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 was detected in lipopolysaccharide (LPS)-treated HL-1 cells using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). After overexpression or interference with ZC3H13, Cell Counting Kit-8 measured cell proliferation, flow cytometry detected apoptosis and reactive oxygen species (ROS) accumulation was observed. Then, we identified the potential downstream genes of ZC3H13 through further bioinformatics analysis followed by qRT-PCR and western blotting validation. RESULTS: There were five differentially expressed genes related to m6A, including Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13. The expression of Rrp8, Trmt6, Trmt61a, Ythdf1, and ZC3H13 mRNA was significantly up-regulated in the LPS-treated HL-1 cells, with ZC3H13 having the highest expression. Furthermore, overexpression of ZC3H13 inhibited the proliferation of HL-1 cells and promoted apoptosis and ROS accumulation. While, interfering with ZC3H13 promoted the proliferation of LPS-treated HL-1 cells, and reduced apoptosis and ROS accumulation. Additionally, si-ZC3H13 promoted the expression of Pnn, GPX4, and SLC7A11; while inhibiting the expression of Rbm25 and Caspase 3. CONCLUSIONS: In a word, the silence of ZC3H13 increased the proliferation and ferroptosis-related protein expression, decreased apoptosis and ROS accumulation, as well as maybe by regulating Pnn and Rbm25 expression.

ZC3H13 promotes ITGA6 m6A modification for chronic obstructive pulmonary disease progression.

Chronic obstructive pulmonary disease (COPD) is potentially fatal, and as society ages, its effects on human health are predicted to deteriorate. The potential function of m6A modifications within COPD has become a hot topic recently. This study was conducted to clarify the function and related mechanisms of the m6A methylation transferase ZC3H13 in COPD. The expression of m6A-associated protease and ITGA6 in COPD tissues was assessed using GEO data, qRT-PCR, and western blot. COPD models in cells and mice were established through cigarette smoke extract (CSE) and smoke exposure. Inflammatory marker levels were measured by ELISA, apoptosis by flow cytometry, and mRNA stability with Actinomycin D assay. m6A modification levels were checked by MeRIP-PCR. HE and Masson staining evaluated lung pathology, and alveolar lavage fluid analysis included total cell count and Giemsa staining. ZC3H13 and METTL3 were differentially expressed m6A regulators in COPD, with ZC3H13 being more significantly upregulated. Further analysis revealed the ZC3H13 expression-related differentially expressed genes (DEGs) functions were enriched in the immunoinflammatory pathway, indicating ZC3H13's involvement in COPD pathogenesis through inflammation, and immune responses. Knockdown studies in cellular and mouse models demonstrated ZC3H13's role in exacerbating COPD symptoms, including inflammation, apoptosis, and EMT, and its suppression led to significant improvements. The identification of ITGA6 as a target gene further elucidated the mechanism, showing that ZC3H13 enhances ITGA6 expression and mRNA stability through m6A modification, influencing bronchial epithelial cell inflammation and fibrosis. In conclusion, targeting ZC3H13/ITGA6 could be an underlying therapeutic approach for treating COPD.

hsa_circ_0101050 regulated by ZC3H13 enhances tumorigenesis in papillary thyroid cancer via m6A modification.

While the regulatory roles of circular RNAs (circRNAs) and zinc finger CCCH-type containing 13 (ZC3H13) were previously reported in various human cancers, the mechanisms underlying their interaction in papillary thyroid cancer (PTC) remain unclear. We aimed to determine the role of hsa_circ_0101050 and its regulatory relationship with ZC3H13 in PTC. The expression levels of hsa_circ_0101050 and ZC3H13 were determined in tumor samples and adjacent normal tissues from 46 patients with PTC and in two PTC cell lines (IHH-4 and PTC-1) using quantitative reverse transcription-polymerase chain reaction. The roles of hsa_circ_0101050 and ZC3H13 in cell viability, wound healing, and migration were determined using knockdown and overexpression approaches in PTC cell lines, and a xenograft model in nude mice was used to determine their role in vivo. Methylated RNA immunoprecipitation assay was used to analyze N6-methyladenosine (m6A) modification of hsa_circ_0101050 by ZC3H13. We found hsa_circ_0101050 overexpression and ZC3H13 downregulation in PTC samples and PTC cell lines. In PTC cell lines, silencing hsa_circ_0101050 reduced cell viability and migration whereas its overexpression promoted an aggressive PTC phenotype. ZC3H13 increased the m6A modification of hsa_circ_0101050 and repressed its expression. ZC3H13 overexpression inhibited PTC cell viability, migration, and invasion, which were reversed in cells overexpressing hsa_circ_0101050. Taken together, these results suggested that the downregulation of hsa_circ_0101050 mediated by ZC3H13 through m6A modification contributed to its oncogenic effect in PTC development, revealing the ZC3H13-m6A-hsa_circ_0101050 as a potential therapeutic target in PTC.

ZC3H13 knockdown enhances the inhibitory effect of sevoflurane on gastric cancer cell malignancy by regulating the N6-methyladenosine modification of the lncRNA DLX6-AS1.

Sevoflurane, an inhalation anesthetic, has been shown to suppress cancer development. In this study, we investigated the specific mechanisms involving sevoflurane, zinc-finger CCCH-type containing 13 (ZC3H13), and lncRNA DLX6-AS1 in gastric cancer (GC) progression, focusing on the N6-methyladenosine (m6A) modification of long non-coding RNAs (lncRNAs). We used quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses to measure the levels of ZC3H13 and lncRNA DLX6-AS1 in GC tissues and cells. Furthermore, we conducted Cell Counting Kit-8, colony formation, Transwell, and tumor xenograft assays to evaluate changes in GC cell malignancy following cell transfection and sevoflurane treatment. Additionally, actinomycin D, methylated RNA immunoprecipitation, and qRT-PCR assays were performed to examine the regulatory effects of ZC3H13 on the DLX6-AS1 m6A modification. We detected elevated levels of ZC3H13 in GC samples, while ZC3H13 silencing inhibited GC cell proliferation, migration, and invasion. Silencing ZC3H13 also enhanced the inhibitory effects of sevoflurane on GC cell malignancy. Moreover, we found that the increased expression of DLX6-AS1 in GC cells could be suppressed by ZC3H13 through the mediation of the m6A modification of DLX6-AS1, thereby reducing DLX6-AS1 stability. In conclusion, ZC3H13 knockdown enhances the inhibitory effect of sevoflurane on GC cell malignancy by inducing DLX6-AS1 m6A modification. Our findings may help identify potential therapeutic targets for the treatment of GC.

Arsenic trioxide suppresses lung adenocarcinoma stem cell stemness by inhibiting m6A modification to promote ferroptosis.

Arsenic trioxide (ATO) is well known for its inhibitory effects on cancer progression, including lung adenocarcinoma (LUAD), but the molecular mechanism remains elusive. This study aimed to investigate the roles of ATO in regulating LUAD stem cells (LASCs) and the underlying mechanisms. To induce LASCs, cells cultured in an F12 medium, containing B27, epidermal growth factor, and basic fibroblast growth factor, induced LASCs. LASCs stemness was assessed through tumor sphere formation assay, and percentages of CD133+ cells were detected by flow cytometry. The Cell Counting Kit-8 method was used to assess LASCs viability, while reactive oxygen species (ROS) and iron ion levels were quantitated by fluorescence microscopy and spectrophotometry, respectively, and total m6A levels were measured by dot blot. Additionally, LASCs mitochondrial alterations were analyzed via transmission electron microscopy. Finally, the tumorigenicity of LASCs was assessed using a cancer cell line-based xenograft model. Tumor sphere formation and CD133 expression were used to validate the successful induction of LASCs from A549 and NCI-H1975 cells. ATO significantly inhibited proliferation, reduced ZC3H13 expression and total m6A modification levels, and increased ROS and iron ion content, but repressed sphere formation and CD133 expression in LASCs. ZC3H13 overexpression or ferrostatin-1 treatment abrogated LASCs stemness inhibition caused by ATO treatment, and interference with ZC3H13 inhibited LASCs stemness. Furthermore, the promotion of LASCs ferroptosis by ATO was effectively mitigated by ZC3H13 overexpression, while interference with ZC3H13 further promoted ferroptosis. Moreover, si-ZC3H13 promoted ferroptosis and impaired stemness in LASCs, which ferrostatin-1 abrogated. Finally, ZC3H13 overexpression alleviated the inhibitory effects of ATO on LASCs tumorigenicity. Taken together, ATO treatment substantially impaired the stemness of LUAD stem cells by promoting the ferroptosis program, which was mediated by its ZC3H13 gene expression inhibition to suppress m6A medication.

Exosome-derived lncRNA A1BG-AS1 attenuates the progression of prostate cancer depending on ZC3H13-mediated m6A modification.

BACKGROUND: Exosome-derived long non-coding RNAs (lncRNAs) and N6-methyladenosine (m6A) modifications of lncRNAs have been shown crucial functions in prostate cancer (PCa). Herein, we aim to investigate the detailed mechanism of exosome-derived lncRNA A1BG-AS1 in PCa process. METHODS: PCa cell exosomes were extracted, exosomal marker proteins (CD63, CD9) were detected utilizing western blotting, and exosomes with overexpressing A1BG-AS1 were co-cultured with targeted PCa cells. qRT-PCR was used to detect A1BG-AS1 expression and m6A methyltransferase ZC3H13 in PCa. Transwell, colony formation and CCK-8 assays were utilized to assess the invasion, migration, and proliferation ability of PCa cells. Then, we performed actinomycin D and MeRIP assays to analyze the regulatory effect of ZC3H13 on A1BG-AS1 mRNA stability and m6A modification level. RESULTS: We observed that A1BG-AS1 and ZC3H13 expression was restricted in PCa tumors. The invasion, proliferation and migratory capacities of PCa cells could be inhibited by up-regulating A1BG-AS1 or by co-culturing with exosomes that up-regulate A1BG-AS1. Additionally, ZC3H13 promoted stable A1BG-AS1 expression by regulating the m6A level of A1BG-AS1. CONCLUSION: Exosomal A1BG-AS1 was m6A-modified by the m6A methyltransferase ZC3H13 to stabilize expression and thus prevent PCa cell malignancy. These findings offer a possible target for clinical therapy of PCa.

The yeast RNA methylation complex consists of conserved yet reconfigured components with m6A-dependent and independent roles.

N6-methyladenosine (m6A), the most abundant mRNA modification, is deposited in mammals/insects/plants by m6A methyltransferase complexes (MTC) comprising a catalytic subunit and at least five additional proteins. The yeast MTC is critical for meiosis and was known to comprise three proteins, of which two were conserved. We uncover three novel MTC components (Kar4/Ygl036w-Vir1/Dyn2). All MTC subunits, except for Dyn2, are essential for m6A deposition and have corresponding mammalian MTC orthologues. Unlike the mammalian bipartite MTC, the yeast MTC is unipartite, yet multifunctional. The mRNA interacting module, comprising Ime4, Mum2, Vir1, and Kar4, exerts the MTC's m6A-independent function, while Slz1 enables the MTC catalytic function in m6A deposition. Both functions are critical for meiotic progression. Kar4 also has a mechanistically separate role from the MTC during mating. The yeast MTC constituents play distinguishable m6A-dependent, MTC-dependent, and MTC-independent functions, highlighting their complexity and paving the path towards dissecting multi-layered MTC functions in mammals.

ZC3H13-mediated N6-methyladenosine modification of PHF10 is impaired by fisetin which inhibits the DNA damage response in pancreatic cancer.

DNA damage repair is a major barrier for chemotherapy efficacy of pancreatic ductal adenocarcinoma (PDAC), including the efficacy of platinum-based and gemcitabine/nab-paclitaxel treatments. N6-methyladenosine modifications (m6A) have recently been reported to play a role in homologous recombination (HR) repair of DNA double strand breaks (DSBs); however, the mechanism of action remains unknown. Our previous work indicated that fisetin may be a promising anti-tumour agent that induces DNA damage. In this study, we reported that fisetin induced DSBs and suppressed HR repair through m6A modification in PDAC cells. The m6A writer ZC3H13 and PHF10, which is a subunit of the PBAF chromatin remodelling complex, were identified as the main molecules affected by fisetin treatment. To our knowledge, it's the first time that PHF10 was found and involved in the DNA damage response. PHF10 loss-of-function resulted in elevated recruitment of γH2AX, RAD51, and 53BP1 to DSB sites and decreased HR repair efficiency. Moreover, ZC3H13 knockdown downregulated the m6A methylation of PHF10 and decreased PHF10 translation in a YTHDF1-dependent manner. In conclusion, our study demonstrates that fisetin enhanced DSBs via ZC3Hl3-mediated m6A modification of PHF10, which may provide insight into novel therapeutic approaches for PDAC.

IGF2BP3 is an essential N6-methyladenosine biotarget for suppressing ferroptosis in lung adenocarcinoma cells.

A lack of promising targets leads to poor prognosis in patients with lung adenocarcinoma (LUAD). Therefore, it is urgent to identify novel therapeutic targets. The importance of the N6-methyladenosine (m6A) RNA modification has been demonstrated in various types of tumors; however, knowledge of m6A-related proteins in LUAD is still limited. Here, we found that insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3), an m6A reader protein, is highly expressed in LUAD and associated with poor prognosis. IGF2BP3 desensitizes ferroptosis (a new form of regulated cell death) in a manner dependent on its m6A reading domain and binding capacity to m6A-methylated mRNAs encoding anti-ferroptotic factors, including but not limited to glutathione peroxidase 4 (GPX4), solute carrier family 3 member 2 (SLC3A2), acyl-CoA synthetase long chain family member 3 (ACSL3), and ferritin heavy chain 1 (FTH1). After IGF2BP3 overexpression, expression levels and mRNA stabilities of these anti-ferroptotic factors were successfully sustained. Notably, significant correlations between SLC3A2, ACSL3, and IGF2BP3 were revealed in clinical LUAD specimens, further establishing the essential role of IGF2BP3 in desensitizing ferroptosis. Inducing ferroptosis has been gradually accepted as an alternative strategy to treat tumors. Thus, IGF2BP3 could be a potential target for the future development of new biomaterial-associated therapeutic anti-tumor drugs.