1
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Mars JC, Culjkovic-Kraljacic B, Borden KL. eIF4E orchestrates mRNA processing, RNA export and translation to modify specific protein production. Nucleus 2024; 15:2360196. [PMID: 38880976 PMCID: PMC11185188 DOI: 10.1080/19491034.2024.2360196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/22/2024] [Indexed: 06/18/2024] Open
Abstract
The eukaryotic translation initiation factor eIF4E acts as a multifunctional factor that simultaneously influences mRNA processing, export, and translation in many organisms. Its multifactorial effects are derived from its capacity to bind to the methyl-7-guanosine cap on the 5'end of mRNAs and thus can act as a cap chaperone for transcripts in the nucleus and cytoplasm. In this review, we describe the multifactorial roles of eIF4E in major mRNA-processing events including capping, splicing, cleavage and polyadenylation, nuclear export and translation. We discuss the evidence that eIF4E acts at two levels to generate widescale changes to processing, export and ultimately the protein produced. First, eIF4E alters the production of components of the mRNA processing machinery, supporting a widescale reprogramming of multiple mRNA processing events. In this way, eIF4E can modulate mRNA processing without physically interacting with target transcripts. Second, eIF4E also physically interacts with both capped mRNAs and components of the RNA processing or translation machineries. Further, specific mRNAs are sensitive to eIF4E only in particular mRNA processing events. This selectivity is governed by the presence of cis-acting elements within mRNAs known as USER codes that recruit relevant co-factors engaging the appropriate machinery. In all, we describe the molecular bases for eIF4E's multifactorial function and relevant regulatory pathways, discuss the basis for selectivity, present a compendium of ~80 eIF4E-interacting factors which play roles in these activities and provide an overview of the relevance of its functions to its oncogenic potential. Finally, we summarize early-stage clinical studies targeting eIF4E in cancer.
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Affiliation(s)
- Jean-Clément Mars
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
| | - Biljana Culjkovic-Kraljacic
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
| | - Katherine L.B. Borden
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
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2
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Mahé M, Rios-Fuller T, Katsara O, Schneider RJ. Non-canonical mRNA translation initiation in cell stress and cancer. NAR Cancer 2024; 6:zcae026. [PMID: 38828390 PMCID: PMC11140632 DOI: 10.1093/narcan/zcae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/08/2024] [Accepted: 05/29/2024] [Indexed: 06/05/2024] Open
Abstract
The now well described canonical mRNA translation initiation mechanism of m7G 'cap' recognition by cap-binding protein eIF4E and assembly of the canonical pre-initiation complex consisting of scaffolding protein eIF4G and RNA helicase eIF4A has historically been thought to describe all cellular mRNA translation. However, the past decade has seen the discovery of alternative mechanisms to canonical eIF4E mediated mRNA translation initiation. Studies have shown that non-canonical alternate mechanisms of cellular mRNA translation initiation, whether cap-dependent or independent, serve to provide selective translation of mRNAs under cell physiological and pathological stress conditions. These conditions typically involve the global downregulation of canonical eIF4E1/cap-mediated mRNA translation, and selective translational reprogramming of the cell proteome, as occurs in tumor development and malignant progression. Cancer cells must be able to maintain physiological plasticity to acquire a migratory phenotype, invade tissues, metastasize, survive and adapt to severe microenvironmental stress conditions that involve inhibition of canonical mRNA translation initiation. In this review we describe the emerging, important role of non-canonical, alternate mechanisms of mRNA translation initiation in cancer, particularly in adaptation to stresses and the phenotypic cell fate changes involved in malignant progression and metastasis. These alternate translation initiation mechanisms provide new targets for oncology therapeutics development.
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Affiliation(s)
- Mélanie Mahé
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Tiffany Rios-Fuller
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Olga Katsara
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
| | - Robert J Schneider
- Department of Microbiology, NYU Grossman School of Medicine, New York, NY 10016, USA
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3
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Weiss B, Dikstein R. Unraveling the landscapes and regulation of scanning, leaky scanning, and 48S initiation complex conformations. Cell Rep 2024; 43:114126. [PMID: 38630588 DOI: 10.1016/j.celrep.2024.114126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 01/19/2024] [Accepted: 04/02/2024] [Indexed: 04/19/2024] Open
Abstract
Scanning and initiation are critical steps in translation. Here, we utilized translation complex profiling (TCP-seq) to investigate 48S organization and eIF4G1-eIF1 inhibition impact. We provide global views of scanning and leaky scanning, uncovering a central role of eIF4G1-eIF1 in their regulation. We confirm AUG context importance, with non-leaky genes featuring a Kozak context and cytosine at positions -1 and +5. Capturing 48S complexes associated with eIF1, eIF4G1, eIF3, and eIF2 through selective TCP-seq revealed that the eIF3-scanning ribosome is highly vulnerable to eIF4G1-eIF1 inhibition, and eIF1 tends to dissociate upon AUG recognition. Initiation-site footprint analysis revealed a class spanning -12 to +18/19 from the AUG, representing the entire 48S and enriched with eIF2, eIF1, and eIF4G1, indicative of early initiation. Another eIF3-dependent class extends up to +26 and exhibits reduced eIF2 and eIF4G1 association, suggesting a late/alternative initiation complex. Our analysis provides an overview of scanning, initiation, and evidence for conformational rearrangements in vivo.
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Affiliation(s)
- Benjamin Weiss
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel.
| | - Rivka Dikstein
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel.
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4
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Bhatter N, Dmitriev SE, Ivanov P. Cell death or survival: Insights into the role of mRNA translational control. Semin Cell Dev Biol 2024; 154:138-154. [PMID: 37357122 PMCID: PMC10695129 DOI: 10.1016/j.semcdb.2023.06.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 06/15/2023] [Accepted: 06/15/2023] [Indexed: 06/27/2023]
Abstract
Cellular stress is an intrinsic part of cell physiology that underlines cell survival or death. The ability of mammalian cells to regulate global protein synthesis (aka translational control) represents a critical, yet underappreciated, layer of regulation during the stress response. Various cellular stress response pathways monitor conditions of cell growth and subsequently reshape the cellular translatome to optimize translational outputs. On the molecular level, such translational reprogramming involves an intricate network of interactions between translation machinery, RNA-binding proteins, mRNAs, and non-protein coding RNAs. In this review, we will discuss molecular mechanisms, signaling pathways, and targets of translational control that contribute to cellular adaptation to stress and to cell survival or death.
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Affiliation(s)
- Nupur Bhatter
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Sergey E Dmitriev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | - Pavel Ivanov
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA, USA; Harvard Initiative for RNA Medicine, Boston, Massachusetts, USA.
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5
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Lorenzo-Orts L, Strobl M, Steinmetz B, Leesch F, Pribitzer C, Roehsner J, Schutzbier M, Dürnberger G, Pauli A. eIF4E1b is a non-canonical eIF4E protecting maternal dormant mRNAs. EMBO Rep 2024; 25:404-427. [PMID: 38177902 PMCID: PMC10883267 DOI: 10.1038/s44319-023-00006-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 10/31/2023] [Accepted: 11/08/2023] [Indexed: 01/06/2024] Open
Abstract
Maternal mRNAs are essential for protein synthesis during oogenesis and early embryogenesis. To adapt translation to specific needs during development, maternal mRNAs are translationally repressed by shortening the polyA tails. While mRNA deadenylation is associated with decapping and degradation in somatic cells, maternal mRNAs with short polyA tails are stable. Here we report that the germline-specific eIF4E paralog, eIF4E1b, is essential for zebrafish oogenesis. eIF4E1b localizes to P-bodies in zebrafish embryos and binds to mRNAs with reported short or no polyA tails, including histone mRNAs. Loss of eIF4E1b results in reduced histone mRNA levels in early gonads, consistent with a role in mRNA storage. Using mouse and human eIF4E1Bs (in vitro) and zebrafish eIF4E1b (in vivo), we show that unlike canonical eIF4Es, eIF4E1b does not interact with eIF4G to initiate translation. Instead, eIF4E1b interacts with the translational repressor eIF4ENIF1, which is required for eIF4E1b localization to P-bodies. Our study is consistent with an important role of eIF4E1b in regulating mRNA dormancy and provides new insights into fundamental post-transcriptional regulatory principles governing early vertebrate development.
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Affiliation(s)
- Laura Lorenzo-Orts
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria.
| | - Marcus Strobl
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Benjamin Steinmetz
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
- Department of Biology, Institute of Molecular Systems Biology, ETH Zürich, 8093, Zurich, Switzerland
| | - Friederike Leesch
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Carina Pribitzer
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Josef Roehsner
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, Vienna, Austria
| | - Michael Schutzbier
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Gerhard Dürnberger
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria
| | - Andrea Pauli
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), 1030, Vienna, Austria.
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Li J, Zheng L, Song L, Dong Z, Bai W, Qi L. Identification and validation of N 7 -methylguanosine-associated gene NCBP1 as prognostic and immune-associated biomarkers in breast cancer patients. J Cell Mol Med 2024; 28:e18067. [PMID: 38071502 PMCID: PMC10826432 DOI: 10.1111/jcmm.18067] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/14/2023] [Accepted: 11/22/2023] [Indexed: 02/01/2024] Open
Abstract
We intend to evaluate the importance of N7 -methylguanosine (m7G) for the prognosis of breast cancer (BC). We gained 29 m7G-related genes from the published literature and among them, 16 m7G-related genes were found to have differential expression. Five differentially expressed genes (CYFIP1, EIF4E, EIF4E3, NCBP1 and WDR4) were linked to overall survival. This suggests that m7G-related genes might be prognostic or therapeutic targets for BC patients. We put the five genes to LASSO regression analysis to create a four-gene signature, including EIF4E, EIF4E3, WDR4 and NCBP1, that divides samples into two risky groups. Survival was drastically worsened in a high-risk group (p < 0.001). The signature's predictive capacity was demonstrated using ROC (10-year AUC 0.689; 10-year AUC 0.615; 3-year AUC 0.602). We found that immune status was significantly different between the two risk groups. In particular, NCBP1 also has a poor prognosis, with higher diagnostic value in ROC. NCBP1 also has different immune states according to its high or low expression. Meanwhile, knockdown of NCBP1 suppresses BC malignancy in vitro. Therefore, m7G RNA regulators are crucial participants in BC and four-gene mRNA levels are important predictors of prognosis. NCBP1 plays a critical target of m7G mechanism in BC.
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Affiliation(s)
- Jianrong Li
- Department of General Surgery SciencesShanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/ Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuanChina
| | - Lin Zheng
- Department of Vascular SurgeryThe Second Hospital of Shanxi Medical UniversityTaiyuanChina
| | - Liying Song
- Thyroid Surgery DepartmentFirst Hospital of Shanxi Medical UniversityTaiyuanChina
| | - Zhuanxia Dong
- GastroenterologyShanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuanChina
| | - Wenqi Bai
- Department of General Surgery SciencesShanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/ Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuanChina
| | - Liqiang Qi
- Department of Breast Surgery, National Cancer Center/National Cancer Clinical Medical Research Center/Cancer HospitalChinese Academy of Medical SciencesBeijingChina
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7
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Dong Y, Srour O, Lukhovitskaya N, Makarian J, Baumberger N, Galzitskaya O, Elser D, Schepetilnikov M, Ryabova LA. Functional analogs of mammalian 4E-BPs reveal a role for TOR in global plant translation. Cell Rep 2023; 42:112892. [PMID: 37516965 DOI: 10.1016/j.celrep.2023.112892] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 05/22/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
Mammalian/mechanistic target of rapamycin (mTOR) regulates global protein synthesis through inactivation of eIF4E-binding proteins (m4E-BPs) in response to nutrient and energy availability. Until now, 4E-BPs have been considered as metazoan inventions, and how target of rapamycin (TOR) controls cap-dependent translation initiation in plants remains obscure. Here, we present short unstructured 4E-BP-like Arabidopsis proteins (4EBP1/4EBP2) that are non-homologous to m4E-BPs except for the eIF4E-binding motif and TOR phosphorylation sites. Unphosphorylated 4EBPs exhibit strong affinity toward eIF4Es and can inhibit formation of the cap-binding complex. Upon TOR activation, 4EBPs are phosphorylated, probably when bound directly to TOR, and likely relocated to ribosomes. 4EBPs can suppress a distinct set of mRNAs; 4EBP2 predominantly inhibits translation of core cell-cycle regulators CycB1;1 and CycD1;1, whereas 4EBP1 interferes with chlorophyll biosynthesis. Accordingly, 4EBP2 overexpression halts early seedling development, which is overcome by induction of Glc/Suc-TOR signaling. Thus, TOR regulates cap-dependent translation initiation by inactivating atypical 4EBPs in plants.
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Affiliation(s)
- Yihan Dong
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Ola Srour
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nina Lukhovitskaya
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Joelle Makarian
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Nicolas Baumberger
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Oxana Galzitskaya
- Institute of Protein Research of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - David Elser
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France
| | - Mikhail Schepetilnikov
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
| | - Lyubov A Ryabova
- Institut de biologie moléculaire des plantes UPR2357 du CNRS, Université de Strasbourg, Strasbourg, France.
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8
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Tang Q, Li L, Wang Y, Wu P, Hou X, Ouyang J, Fan C, Li Z, Wang F, Guo C, Zhou M, Liao Q, Wang H, Xiang B, Jiang W, Li G, Zeng Z, Xiong W. RNA modifications in cancer. Br J Cancer 2023; 129:204-221. [PMID: 37095185 PMCID: PMC10338518 DOI: 10.1038/s41416-023-02275-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 03/30/2023] [Accepted: 04/06/2023] [Indexed: 04/26/2023] Open
Abstract
Currently, more than 170 modifications have been identified on RNA. Among these RNA modifications, various methylations account for two-thirds of total cases and exist on almost all RNAs. Roles of RNA modifications in cancer are garnering increasing interest. The research on m6A RNA methylation in cancer is in full swing at present. However, there are still many other popular RNA modifications involved in the regulation of gene expression post-transcriptionally besides m6A RNA methylation. In this review, we focus on several important RNA modifications including m1A, m5C, m7G, 2'-O-Me, Ψ and A-to-I editing in cancer, which will provide a new perspective on tumourigenesis by peeking into the complex regulatory network of epigenetic RNA modifications, transcript processing, and protein translation.
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Affiliation(s)
- Qiling Tang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Lvyuan Li
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Yumin Wang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, 410078, Changsha, Hunan, China
| | - Pan Wu
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Xiangchan Hou
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Jiawei Ouyang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Chunmei Fan
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Zheng Li
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Fuyan Wang
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Can Guo
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Ming Zhou
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Qianjin Liao
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
| | - Hui Wang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
| | - Bo Xiang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Weihong Jiang
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University, 410078, Changsha, Hunan, China
| | - Guiyuan Li
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Zhaoyang Zeng
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China
| | - Wei Xiong
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, 410078, Changsha, Hunan, China.
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Central South University, 410078, Changsha, Hunan, China.
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9
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Xu X, Zhao Y, Ying Y, Zhu H, Luo J, Mou T, Zhang Z. m7G-related genes-NCBP2 and EIF4E3 determine immune contexture in head and neck squamous cell carcinoma by regulating CCL4/CCL5 expression. Mol Carcinog 2023; 62:1091-1106. [PMID: 37067401 DOI: 10.1002/mc.23548] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 03/15/2023] [Accepted: 04/09/2023] [Indexed: 04/18/2023]
Abstract
Aberrant N7 -methylguanosine (m7G) levels closely correlate with tumor genesis and progression. NCBP2 and EIF4E3 are two important m7G-related cap-binding genes. This study aimed to identify the relationship between the EIF4E3/NCBP2 function and immunological characteristics of head and neck squamous cell carcinoma (HNSCC). Hierarchical clustering was employed in classifying HNSCC patients into two groups based on the expressions of NCBP2 and EIF4E3. The differentially expressed genes were identified between the two groups, and GO functional enrichment was subsequently performed. Weighted gene co-expression network analysis was conducted to identify the hub genes related to EIF4E3/NCBP2 expression and immunity. The differential infiltration of immune cells and the response to immunotherapy were compared between the two groups. Single-cell sequence and trajectory analyses were performed to predict cell differentiation and display the expression of EIF4E3/NCBP2 in each state. In addition, quantitative real-time PCR, spatial transcriptome analysis, transwell assay, and western blotting were conducted to verify the biological function of EIF4E3/NCBP2. Here, group A showed a higher EIF4E3 expression and a lower NCBP2 expression, which had higher immune scores, proportion of most immune cells, immune activities, expression of immunomodulatory targets, and a better response to cancer immunotherapy. Besides, 56 hub molecules with notable immune regulation significance were identified. A risk model containing 17 hub genes and a prognostic nomogram was successfully established. Moreover, HNSCC tissues had a lower EIF4E3 expression and a higher NCBP2 expression than normal tissues. NCBP2 and EIF4E3 played a vital role in the differentiation of monocytes. Furthermore, the expression of CCL4/CCL5 can be regulated via EIF4E3 overexpression and NCBP2 knockdown. Collectively, NCBP2 and EIF4E3 can affect downstream gene expression, as well as immune contexture and response to immunotherapy, which could induce "cold-to-hot" tumor transformation in HNSCC patients.
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Affiliation(s)
- Xuhui Xu
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
| | - Yue Zhao
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
| | - Yukang Ying
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
| | - Haoran Zhu
- Health Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi, China
| | - Jun Luo
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
| | - Tingchen Mou
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
| | - Zhenxing Zhang
- Department of Stomatology, Taizhou Central Hospital (Taizhou University Hospital), Taizhou, Zhejiang, China
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10
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Liang M, Hody C, Yammine V, Soin R, Sun Y, Lin X, Tian X, Meurs R, Perdrau C, Delacourt N, Oumalis M, Andris F, Conrard L, Kruys V, Gueydan C. eIF4EHP promotes Ldh mRNA translation in and fruit fly adaptation to hypoxia. EMBO Rep 2023; 24:e56460. [PMID: 37144276 PMCID: PMC10328074 DOI: 10.15252/embr.202256460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 04/16/2023] [Accepted: 04/21/2023] [Indexed: 05/06/2023] Open
Abstract
Hypoxia induces profound modifications in the gene expression program of eukaryotic cells due to lowered ATP supply resulting from the blockade of oxidative phosphorylation. One significant consequence of oxygen deprivation is the massive repression of protein synthesis, leaving a limited set of mRNAs to be translated. Drosophila melanogaster is strongly resistant to oxygen fluctuations; however, the mechanisms allowing specific mRNA to be translated into hypoxia are still unknown. Here, we show that Ldh mRNA encoding lactate dehydrogenase is highly translated into hypoxia by a mechanism involving a CA-rich motif present in its 3' untranslated region. Furthermore, we identified the cap-binding protein eIF4EHP as a main factor involved in 3'UTR-dependent translation under hypoxia. In accordance with this observation, we show that eIF4EHP is necessary for Drosophila development under low oxygen concentrations and contributes to Drosophila mobility after hypoxic challenge. Altogether, our data bring new insight into mechanisms contributing to LDH production and Drosophila adaptation to oxygen variations.
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Affiliation(s)
- Manfei Liang
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
- Present address:
Medical Science and Technology Innovation CenterShandong First Medical UniversityJinanChina
| | - Clara Hody
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Vanessa Yammine
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Romuald Soin
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Yuqiu Sun
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Xing Lin
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Xiaoying Tian
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Romane Meurs
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Camille Perdrau
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Nadège Delacourt
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Marina Oumalis
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Fabienne Andris
- Laboratoire d'Immunobiologie, Faculté des SciencesUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Louise Conrard
- Center of Microscopy and Molecular Imaging (CMMI)Université libre de Bruxelles (ULB)GosseliesBelgium
| | - Véronique Kruys
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
| | - Cyril Gueydan
- Laboratoire de Biologie Moléculaire du GèneUniversité libre de Bruxelles (ULB)GosseliesBelgium
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11
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Liu Y, Yang D, Liu T, Chen J, Yu J, Yi P. N6-methyladenosine-mediated gene regulation and therapeutic implications. Trends Mol Med 2023; 29:454-467. [PMID: 37068987 DOI: 10.1016/j.molmed.2023.03.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 03/11/2023] [Accepted: 03/20/2023] [Indexed: 04/19/2023]
Abstract
N6-methyladenosine (m6A) RNA methylation is the most abundant form of mRNA modification in eukaryotes and is at the front line of biological and biomedical research. This dynamic and reversible m6A RNA modification determines the fates of modified RNA molecules at the post-transcriptional level, affecting almost all important biological processes. Notably, m6A is also involved in chromatin and transcriptional regulation, while m6A dysregulation is implicated in various diseases. Here, we review current knowledge of post-transcriptional and transcriptional regulatory mechanisms involving m6A modification. We also discuss their involvement in the occurrence and development of diseases, including cancer, as well as potential theranostic targets, in hope of facilitating the translation of preclinical findings to the clinic.
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Affiliation(s)
- Yujiao Liu
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Dan Yang
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Tao Liu
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Jianjun Chen
- Department of Systems Biology, Beckman Research Institute, City of Hope, Los Angeles, CA 91010, USA
| | - Jianhua Yu
- Hematologic Malignancies Research Institute, City of Hope National Medical Center, Los Angeles, CA 91010, USA; Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Los Angeles, CA 91010, USA.
| | - Ping Yi
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China.
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12
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Tseng CS, Chao YW, Liu YH, Huang YS, Chao HW. Dysregulated proteostasis network in neuronal diseases. Front Cell Dev Biol 2023; 11:1075215. [PMID: 36910151 PMCID: PMC9998692 DOI: 10.3389/fcell.2023.1075215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 02/15/2023] [Indexed: 03/14/2023] Open
Abstract
Long-term maintenance of synaptic connections is important for brain function, which depends on varying proteostatic regulations to govern the functional integrity of neuronal proteomes. Proteostasis supports an interconnection of pathways that regulates the fate of proteins from synthesis to degradation. Defects in proteostatic signaling are associated with age-related functional decline and neurodegenerative diseases. Recent studies have advanced our knowledge of how cells have evolved distinct mechanisms to safely control protein homeostasis during synthesis, folding and degradation, and in different subcellular organelles and compartments. Neurodegeneration occurs when these protein quality controls are compromised by accumulated pathogenic proteins or aging to an irreversible state. Consequently, several therapeutic strategies, such as targeting the unfolded protein response and autophagy pathways, have been developed to reduce the burden of misfolded proteins and proved useful in animal models. Here, we present a brief overview of the molecular mechanisms involved in maintaining proteostatic networks, along with some examples linking dysregulated proteostasis to neuronal diseases.
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Affiliation(s)
- Ching-San Tseng
- Department of Anatomy, School of Medicine, China Medical University, Taichung, Taiwan
| | - Yu-Wen Chao
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yi-Hsiang Liu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yi-Shuian Huang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Hsu-Wen Chao
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
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13
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Muñoz-Ayala A, Chimal-Vega B, García-González V. Translation initiation and its relationship with metabolic mechanisms in cancer development, progression and chemoresistance. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 132:111-141. [PMID: 36088073 DOI: 10.1016/bs.apcsb.2022.05.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Pathways that regulate protein homeostasis (proteostasis) in cells range from mRNA processing to protein degradation; perturbations in regulatory mechanisms of these pathways can lead to oncogenic cellular processes. Protein synthesis modulation failures are common phenomena in cancer cells, wherein specific conditions that promote the translation of protein factors promoting carcinogenesis are present. These specific conditions may be favored by metabolic lipid alterations like those found in metabolic syndrome and obesity. Protein translation modifications have been described in obesity, favoring the translation of protein targets that benefit lipid accumulation; a determining factor is the activity of the cap-binding eukaryotic translation initiation factor 4E (eIF4E), a crosstalk in protein translation and lipogenesis. Besides, alterations of protein translation initiation steps are critical participants for the development of both pathogenic conditions, cancer, and obesity. This chapter is focused on the regulation of recognition and processing of carcinogenic-mRNA and the connections among lipid metabolism and cell signaling pathways that promote oncogenesis, tumoral microenvironment generation and potentially the development of chemoresistance. We performed an in-depth analysis of events, such as those occurring in obesity and dyslipidemias, that may influence protein translation, driving the recognition of certain mRNAs and favoring cancer development and chemoresistance.
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Affiliation(s)
- Andrea Muñoz-Ayala
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México
| | - Brenda Chimal-Vega
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México
| | - Victor García-González
- Departamento de Bioquímica, Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali, México; Laboratorio Multidisciplinario de Estudios Metabólicos y Cáncer, Universidad Autónoma de Baja California, Mexicali, México.
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14
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Soichot J, Guttmann N, Rehrauer H, Joller N, Tritten L. Nematode microRNAs can Individually Regulate Interferon Regulatory Factor 4 and mTOR in Differentiating T Helper 2 Lymphocytes and Modulate Cytokine Production in Macrophages. Front Mol Biosci 2022; 9:909312. [PMID: 35836928 PMCID: PMC9274173 DOI: 10.3389/fmolb.2022.909312] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/27/2022] [Indexed: 11/30/2022] Open
Abstract
Parasitic nematodes are masterful immunomodulators. This class of pathogens has evolved a spectrum of sophisticated strategies to regulate and evade host immune responses, mediated through the release of various molecules. In this context, the release of microRNAs (miRNAs), short post-transcriptional regulators of gene expression, has been of particular interest in the host-parasite interplay. Evidence that parasite-derived miRNAs modulate host innate and adaptive immune responses has become increasingly compelling. However, since miRNAs are usually contained in extracellular vesicles containing other mediators, it is difficult to assign an observed effect on host cells to miRNAs specifically. Here, the effects of some abundantly secreted miRNAs by nematodes used as models of gastrointestinal infections (Heligmosomoides polygyrus bakeri, Trichuris muris and Ascaris suum) were evaluated, addressing the potential of parasite miRNAs to impair in vitro differentiation of two important types of immune cells in the context of helminth infections, Th2 lymphocytes and macrophages. Mimicking a continuous exposure to low concentrations of nematode miRNAs, the interferon gamma signaling, the IL-2/STAT5 signaling, and the mTOR signaling pathways were identified as downregulated by Hpo-miR-71-5p. Interferon regulatory factor 4 (Irf4) was validated as a target of Hpo-miR-71-5p, while Mtor is targeted by Asu-miR-791-3p, abundant in the T. muris secretions. By trend, Hpo-miR-71-5p impacts mildly but consistently on the amounts of inflammatory cytokines in unpolarized macrophages but leads to slightly increased IL-10 level in alternatively activated cells. In addition, our data suggests that transfected miRNAs remain for days in recipient cells, and that Hpo-miR-71-5p can incorporate into mouse Argonaute protein complexes. Nematode miRNAs can impair both innate and adaptive arms of host immunity. Hpo-miR-71-5p in particular, absent in mammals, interacts with host genes and pathways with crucial involvement in anthelmintic immune responses. This report brings new insights into the dynamics of miRNA-driven immunomodulation and highlights putative targeted pathways. Although the absolute repression is subtle, it is expected that the dozens of different miRNAs released by nematodes may have a synergistic effect on surrounding host cells.
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Affiliation(s)
- Julien Soichot
- Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Nathalie Guttmann
- Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Hubert Rehrauer
- Functional Genomics Center Zurich, ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Nicole Joller
- Department of Quantitative Biomedicine, University of Zurich, Zurich, Switzerland
| | - Lucienne Tritten
- Institute of Parasitology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- *Correspondence: Lucienne Tritten,
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15
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Boris-Lawrie K, Singh G, Osmer PS, Zucko D, Staller S, Heng X. Anomalous HIV-1 RNA, How Cap-Methylation Segregates Viral Transcripts by Form and Function. Viruses 2022; 14:935. [PMID: 35632676 PMCID: PMC9145092 DOI: 10.3390/v14050935] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/25/2022] [Accepted: 04/25/2022] [Indexed: 12/11/2022] Open
Abstract
The acquisition of m7G-cap-binding proteins is now recognized as a major variable driving the form and function of host RNAs. This manuscript compares the 5'-cap-RNA binding proteins that engage HIV-1 precursor RNAs, host mRNAs, small nuclear (sn)- and small nucleolar (sno) RNAs and sort into disparate RNA-fate pathways. Before completion of the transcription cycle, the transcription start site of nascent class II RNAs is appended to a non-templated guanosine that is methylated (m7G-cap) and bound by hetero-dimeric CBP80-CBP20 cap binding complex (CBC). The CBC is a nexus for the co-transcriptional processing of precursor RNAs to mRNAs and the snRNA and snoRNA of spliceosomal and ribosomal ribonucleoproteins (RNPs). Just as sn/sno-RNAs experience hyper-methylation of m7G-cap to trimethylguanosine (TMG)-cap, so do select HIV RNAs and an emerging cohort of mRNAs. TMG-cap is blocked from Watson:Crick base pairing and disqualified from participating in secondary structure. The HIV TMG-cap has been shown to license select viral transcripts for specialized cap-dependent translation initiation without eIF4E that is dependent upon CBP80/NCBP3. The exceptional activity of HIV precursor RNAs secures their access to maturation pathways of sn/snoRNAs, canonical and non-canonical host mRNAs in proper stoichiometry to execute the retroviral replication cycle.
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Affiliation(s)
- Kathleen Boris-Lawrie
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN 55108, USA; (G.S.); (D.Z.)
| | - Gatikrushna Singh
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN 55108, USA; (G.S.); (D.Z.)
- Department of Neurosurgery, University of Minnesota, Minneapolis, MN 55455, USA
| | - Patrick S. Osmer
- Department of Astronomy, The Ohio State University, Columbus, OH 43210, USA;
| | - Dora Zucko
- Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN 55108, USA; (G.S.); (D.Z.)
| | - Seth Staller
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA;
| | - Xiao Heng
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA;
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16
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Mars JC, Ghram M, Culjkovic-Kraljacic B, Borden KLB. The Cap-Binding Complex CBC and the Eukaryotic Translation Factor eIF4E: Co-Conspirators in Cap-Dependent RNA Maturation and Translation. Cancers (Basel) 2021; 13:6185. [PMID: 34944805 PMCID: PMC8699206 DOI: 10.3390/cancers13246185] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 12/26/2022] Open
Abstract
The translation of RNA into protein is a dynamic process which is heavily regulated during normal cell physiology and can be dysregulated in human malignancies. Its dysregulation can impact selected groups of RNAs, modifying protein levels independently of transcription. Integral to their suitability for translation, RNAs undergo a series of maturation steps including the addition of the m7G cap on the 5' end of RNAs, splicing, as well as cleavage and polyadenylation (CPA). Importantly, each of these steps can be coopted to modify the transcript signal. Factors that bind the m7G cap escort these RNAs through different steps of maturation and thus govern the physical nature of the final transcript product presented to the translation machinery. Here, we describe these steps and how the major m7G cap-binding factors in mammalian cells, the cap binding complex (CBC) and the eukaryotic translation initiation factor eIF4E, are positioned to chaperone transcripts through RNA maturation, nuclear export, and translation in a transcript-specific manner. To conceptualize a framework for the flow and integration of this genetic information, we discuss RNA maturation models and how these integrate with translation. Finally, we discuss how these processes can be coopted by cancer cells and means to target these in malignancy.
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Affiliation(s)
- Jean-Clement Mars
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Mehdi Ghram
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Biljana Culjkovic-Kraljacic
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Katherine L B Borden
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
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