1
|
Zhao B, Deng J, Ma M, Li N, Zhou J, Li X, Luan T. Environmentally relevant concentrations of 2,3,7,8-TCDD induced inhibition of multicellular alternative splicing and transcriptional dysregulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 919:170892. [PMID: 38346650 DOI: 10.1016/j.scitotenv.2024.170892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 02/07/2024] [Accepted: 02/09/2024] [Indexed: 02/17/2024]
Abstract
Alternative splicing (AS), found in approximately 95 % of human genes, significantly amplifies protein diversity and is implicated in disease pathogenesis when dysregulated. However, the precise involvement of AS in the toxic mechanisms induced by TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) remains incompletely elucidated. This study conducted a thorough global AS analysis in six human cell lines following TCDD exposure. Our findings revealed that environmentally relevant concentration (0.1 nM) of TCDD significantly suppressed AS events in all cell types, notably inhibiting diverse splicing events and reducing transcript diversity, potentially attributed to modifications in the splicing patterns of the inhibitory factor family, particularly hnRNP. And we identified 151 genes with substantial AS alterations shared among these cell types, particularly enriched in immune and metabolic pathways. Moreover, TCDD induced cell-specific changes in splicing patterns and transcript levels, with increased sensitivity notably in THP-1 monocyte, potentially linked to aberrant expression of pivotal genes within the spliceosome pathway (DDX5, EFTUD2, PUF60, RBM25, SRSF1, and CRNKL1). This study extends our understanding of disrupted alternative splicing and its relation to the multisystem toxicity of TCDD. It sheds light on how environmental toxins affect post-transcriptional regulatory processes, offering a fresh perspective for toxicology and disease etiology investigations.
Collapse
Affiliation(s)
- Bilin Zhao
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China; Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Jiewei Deng
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China; School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, China; Smart Medical Innovation Technology Center, Guangdong University of Technology, Guangzhou 510006, China
| | - Mei Ma
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Na Li
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Junlin Zhou
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Xinyan Li
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China; School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, China; Smart Medical Innovation Technology Center, Guangdong University of Technology, Guangzhou 510006, China.
| | - Tiangang Luan
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang 515200, China; Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Smart Medical Innovation Technology Center, Guangdong University of Technology, Guangzhou 510006, China
| |
Collapse
|
2
|
Li H, Ma Q, Ren J, Guo W, Feng K, Li Z, Huang T, Cai YD. Immune responses of different COVID-19 vaccination strategies by analyzing single-cell RNA sequencing data from multiple tissues using machine learning methods. Front Genet 2023; 14:1157305. [PMID: 37007947 PMCID: PMC10065150 DOI: 10.3389/fgene.2023.1157305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/07/2023] [Indexed: 03/19/2023] Open
Abstract
Multiple types of COVID-19 vaccines have been shown to be highly effective in preventing SARS-CoV-2 infection and in reducing post-infection symptoms. Almost all of these vaccines induce systemic immune responses, but differences in immune responses induced by different vaccination regimens are evident. This study aimed to reveal the differences in immune gene expression levels of different target cells under different vaccine strategies after SARS-CoV-2 infection in hamsters. A machine learning based process was designed to analyze single-cell transcriptomic data of different cell types from the blood, lung, and nasal mucosa of hamsters infected with SARS-CoV-2, including B and T cells from the blood and nasal cavity, macrophages from the lung and nasal cavity, alveolar epithelial and lung endothelial cells. The cohort was divided into five groups: non-vaccinated (control), 2*adenovirus (two doses of adenovirus vaccine), 2*attenuated (two doses of attenuated virus vaccine), 2*mRNA (two doses of mRNA vaccine), and mRNA/attenuated (primed by mRNA vaccine, boosted by attenuated vaccine). All genes were ranked using five signature ranking methods (LASSO, LightGBM, Monte Carlo feature selection, mRMR, and permutation feature importance). Some key genes that contributed to the analysis of immune changes, such as RPS23, DDX5, PFN1 in immune cells, and IRF9 and MX1 in tissue cells, were screened. Afterward, the five feature sorting lists were fed into the feature incremental selection framework, which contained two classification algorithms (decision tree [DT] and random forest [RF]), to construct optimal classifiers and generate quantitative rules. Results showed that random forest classifiers could provide relative higher performance than decision tree classifiers, whereas the DT classifiers provided quantitative rules that indicated special gene expression levels under different vaccine strategies. These findings may help us to develop better protective vaccination programs and new vaccines.
Collapse
Affiliation(s)
- Hao Li
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - Qinglan Ma
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Jingxin Ren
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Wei Guo
- Key Laboratory of Stem Cell Biology, Shanghai Institutes for Biological Sciences (SIBS), Shanghai Jiao Tong University School of Medicine (SJTUSM), Chinese Academy of Sciences (CAS), Shanghai, China
| | - Kaiyan Feng
- Department of Computer Science, Guangdong AIB Polytechnic College, Guangzhou, China
| | - Zhandong Li
- College of Food Engineering, Jilin Engineering Normal University, Changchun, China
| | - Tao Huang
- Bio-Med Big Data Center, CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yu-Dong Cai
- School of Life Sciences, Shanghai University, Shanghai, China
| |
Collapse
|
3
|
Bonaventure B, Goujon C. DExH/D-box helicases at the frontline of intrinsic and innate immunity against viral infections. J Gen Virol 2022; 103. [PMID: 36006669 DOI: 10.1099/jgv.0.001766] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
Abstract
DExH/D-box helicases are essential nucleic acid and ribonucleoprotein remodelers involved in all aspects of nucleic acid metabolism including replication, gene expression and post-transcriptional modifications. In parallel to their importance in basic cellular functions, DExH/D-box helicases play multiple roles in viral life cycles, with some of them highjacked by viruses or negatively regulating innate immune activation. However, other DExH/D-box helicases have recurrently been highlighted as direct antiviral effectors or as positive regulators of innate immune activation. Innate immunity relies on the ability of Pathogen Recognition Receptors to recognize viral signatures and trigger the production of interferons (IFNs) and pro-inflammatory cytokines. Secreted IFNs interact with their receptors to establish antiviral cellular reprogramming via expression regulation of the interferon-stimulated genes (ISGs). Several DExH/D-box helicases have been reported to act as viral sensors (DDX3, DDX41, DHX9, DDX1/DDX21/DHX36 complex), and others to play roles in innate immune activation (DDX60, DDX60L, DDX23). In contrast, the DDX39A, DDX46, DDX5 and DDX24 helicases act as negative regulators and impede IFN production upon viral infection. Beyond their role in viral sensing, the ISGs DDX60 and DDX60L act as viral inhibitors. Interestingly, the constitutively expressed DEAD-box helicases DDX56, DDX17, DDX42 intrinsically restrict viral replication. Hence, DExH/D-box helicases appear to form a multilayer network of primary and secondary factors involved in both intrinsic and innate antiviral immunity. In this review, we highlight recent findings on the extent of antiviral defences played by helicases and emphasize the need to better understand their immune functions as well as their complex interplay.
Collapse
Affiliation(s)
- Boris Bonaventure
- IRIM, CNRS, Montpellier University, France.,Present address: Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | |
Collapse
|
4
|
DEAD-Box RNA Helicases in Cell Cycle Control and Clinical Therapy. Cells 2021; 10:cells10061540. [PMID: 34207140 PMCID: PMC8234093 DOI: 10.3390/cells10061540] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/11/2021] [Accepted: 06/15/2021] [Indexed: 12/11/2022] Open
Abstract
Cell cycle is regulated through numerous signaling pathways that determine whether cells will proliferate, remain quiescent, arrest, or undergo apoptosis. Abnormal cell cycle regulation has been linked to many diseases. Thus, there is an urgent need to understand the diverse molecular mechanisms of how the cell cycle is controlled. RNA helicases constitute a large family of proteins with functions in all aspects of RNA metabolism, including unwinding or annealing of RNA molecules to regulate pre-mRNA, rRNA and miRNA processing, clamping protein complexes on RNA, or remodeling ribonucleoprotein complexes, to regulate gene expression. RNA helicases also regulate the activity of specific proteins through direct interaction. Abnormal expression of RNA helicases has been associated with different diseases, including cancer, neurological disorders, aging, and autosomal dominant polycystic kidney disease (ADPKD) via regulation of a diverse range of cellular processes such as cell proliferation, cell cycle arrest, and apoptosis. Recent studies showed that RNA helicases participate in the regulation of the cell cycle progression at each cell cycle phase, including G1-S transition, S phase, G2-M transition, mitosis, and cytokinesis. In this review, we discuss the essential roles and mechanisms of RNA helicases in the regulation of the cell cycle at different phases. For that, RNA helicases provide a rich source of targets for the development of therapeutic or prophylactic drugs. We also discuss the different targeting strategies against RNA helicases, the different types of compounds explored, the proposed inhibitory mechanisms of the compounds on specific RNA helicases, and the therapeutic potential of these compounds in the treatment of various disorders.
Collapse
|
5
|
Sergeeva O, Zatsepin T. RNA Helicases as Shadow Modulators of Cell Cycle Progression. Int J Mol Sci 2021; 22:2984. [PMID: 33804185 PMCID: PMC8001981 DOI: 10.3390/ijms22062984] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
The progress of the cell cycle is directly regulated by modulation of cyclins and cyclin-dependent kinases. However, many proteins that control DNA replication, RNA transcription and the synthesis and degradation of proteins can manage the activity or levels of master cell cycle regulators. Among them, RNA helicases are key participants in RNA metabolism involved in the global or specific tuning of cell cycle regulators at the level of transcription and translation. Several RNA helicases have been recently evaluated as promising therapeutic targets, including eIF4A, DDX3 and DDX5. However, targeting RNA helicases can result in side effects due to the influence on the cell cycle. In this review, we discuss direct and indirect participation of RNA helicases in the regulation of the cell cycle in order to draw attention to downstream events that may occur after suppression or inhibition of RNA helicases.
Collapse
Affiliation(s)
- Olga Sergeeva
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
| | - Timofei Zatsepin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30b1, 121205 Moscow, Russia;
- Department of Chemistry, Lomonosov Moscow State University, 119992 Moscow, Russia
| |
Collapse
|
6
|
You Z, Liu C, Wang C, Ling Z, Wang Y, Wang Y, Zhang M, Chen S, Xu B, Guan H, Chen M. LncRNA CCAT1 Promotes Prostate Cancer Cell Proliferation by Interacting with DDX5 and MIR-28-5P. Mol Cancer Ther 2019; 18:2469-2479. [PMID: 31387890 DOI: 10.1158/1535-7163.mct-19-0095] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 06/11/2019] [Accepted: 07/29/2019] [Indexed: 01/17/2023]
Abstract
Accumulated evidence indicates that CCAT1 functions as an oncogene in the progression of a variety of tumors. However, little is known as to how CCAT1 impacts tumorigenesis in human prostate cancer. In this study, we found from The Cancer Genome Atlas and Memorial Sloan Kettering Cancer Center database that CCAT1 is highly upregulated in castration-resistant prostate cancer (CRPC) compared with androgen-dependent prostate cancer (ADPC). Higher level of CCAT1 leads to increased mortality in patients with CRPC. In vitro and in vivo studies show that CCAT1 promotes prostate cancer cell proliferation as well as the tumor growth of prostate cancer xenografts. Mechanistically, in cytoplasm, CCAT1 sponges MIR-28-5P to prevent the anticancer effect. In nucleus, CCAT1 acts as a scaffold for DDX5 (P68) and AR transcriptional complex to facilitate the expression of AR-regulated genes, thus stimulating CRPC progression. Our findings suggest that CCAT1 is an oncogenic factor in the progression of CRPC with different regulatory mechanisms in the nucleus and cytoplasm of cells.
Collapse
Affiliation(s)
- Zonghao You
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China.,Surgical Research Center, Institute of Urology, Medical School of Southeast University, Nanjing, China
| | - Chunhui Liu
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China
| | - Can Wang
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China
| | - Zhixin Ling
- Department of Urology, The First Affiliated Hospital of SooChow University, Suzhou, China
| | - Yiduo Wang
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China
| | - Yali Wang
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China
| | - Minghao Zhang
- Surgical Research Center, Institute of Urology, Medical School of Southeast University, Nanjing, China
| | - Shuqiu Chen
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China
| | - Bin Xu
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China.
| | - Han Guan
- Department of Urology, The First Affiliated Hospital of Bengbu Medical College, Bengbu, China.
| | - Ming Chen
- Department of Urology, Affiliated Zhongda Hospital of Southeast University, Nanjing, China.
| |
Collapse
|
7
|
DDX5 plays essential transcriptional and post-transcriptional roles in the maintenance and function of spermatogonia. Nat Commun 2019; 10:2278. [PMID: 31123254 PMCID: PMC6533336 DOI: 10.1038/s41467-019-09972-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/02/2019] [Indexed: 02/07/2023] Open
Abstract
Mammalian spermatogenesis is sustained by mitotic germ cells with self-renewal potential known as undifferentiated spermatogonia. Maintenance of undifferentiated spermatogonia and spermatogenesis is dependent on tightly co-ordinated transcriptional and post-transcriptional mechanisms. The RNA helicase DDX5 is expressed by spermatogonia but roles in spermatogenesis are unexplored. Using an inducible knockout mouse model, we characterise an essential role for DDX5 in spermatogonial maintenance and show that Ddx5 is indispensable for male fertility. We demonstrate that DDX5 regulates appropriate splicing of key genes necessary for spermatogenesis. Moreover, DDX5 regulates expression of cell cycle genes in undifferentiated spermatogonia post-transcriptionally and is required for cell proliferation and survival. DDX5 can also act as a transcriptional co-activator and we demonstrate that DDX5 interacts with PLZF, a transcription factor required for germline maintenance, to co-regulate select target genes. Combined, our data reveal a critical multifunctional role for DDX5 in regulating gene expression programmes and activity of undifferentiated spermatogonia. Sustained sperm production is dependent on activity of undifferentiated spermatogonia. Here, the authors demonstrate an essential role for RNA helicase DDX5 in maintenance of spermatogonia in adults through control of gene transcription plus RNA processing and export.
Collapse
|
8
|
Huan W, Zhang J, Li Y, Zhi K. Involvement of DHX9/YB-1 complex induced alternative splicing of Krüppel-like factor 5 mRNA in phenotypic transformation of vascular smooth muscle cells. Am J Physiol Cell Physiol 2019; 317:C262-C269. [PMID: 31116584 DOI: 10.1152/ajpcell.00067.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Phenotypic transformation of vascular smooth muscle cells is a key phenomenon in the development of aortic dissection disease. However, the molecular mechanisms underlying this phenomenon have not been fully understood. We used β-BAPN combined with ANG II treatment to establish a disease model of acute aortic dissection (AAD) in mice. We first examined the gene expression profile of aortic tissue in mice with AAD using a gene chip, followed by confirmation of DExH-box helicase 9 (DHX9) expression using RT-PCR, Western blot, and immunofluorescence analysis. We further developed vascular smooth muscle cell-specific DHX9 conditional knockout mice and conducted differential and functional analysis of gene expression and alternative splicing in mouse vascular smooth muscle cells. Finally, we examined the involvement of DHX9 in Krüppel-like factor 5 (KLF5) mRNA alternative splicing. Our study reported a significant decrease in the expression of DHX9 in the vascular smooth muscle cells (VSMCs) of mice with AAD. The smooth muscle cell-specific knockout of DHX9 exacerbated the development of AAD and altered the transcriptional level expression of many smooth muscle cell phenotype-related genes. Finally, we reported that DHX9 may induce alternative splicing of KLF5 mRNA by bridging YB-1. These results together suggested a new pathogenic mechanism underlying the development of AAD, and future research of this mechanism may help identify effective therapeutic intervention for AAD.
Collapse
Affiliation(s)
- Wei Huan
- Department of Vascular Surgery, Changzheng Hospital, The Second Military Medical University, Shanghai, China
| | - Jing Zhang
- Department of Cardiovascular Surgery, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yingke Li
- Department of Anesthesiology, Changzheng Hospital, The Second Military Medical University, Shanghai, China
| | - Kangkang Zhi
- Department of Vascular Surgery, Changzheng Hospital, The Second Military Medical University, Shanghai, China
| |
Collapse
|
9
|
Wang R, Bao H, Du W, Chen X, Liu H, Han D, Wang L, Wu J, Wang C, Yang M, Liu Z, Zhang N, Teng L. P68 RNA helicase promotes invasion of glioma cells through negatively regulating DUSP5. Cancer Sci 2019; 110:107-117. [PMID: 30387548 PMCID: PMC6317933 DOI: 10.1111/cas.13858] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 10/29/2018] [Accepted: 10/30/2018] [Indexed: 12/30/2022] Open
Abstract
Gliomas are the most common central nervous system tumors. They show malignant characteristics indicating rapid proliferation and a high invasive capacity and are associated with a poor prognosis. In our previous study, p68 was overexpressed in glioma cells and correlated with both the degree of glioma differentiation and poor overall survival. Downregulating p68 significantly suppressed proliferation in glioma cells. Moreover, we found that the p68 gene promoted glioma cell growth by activating the nuclear factor-κB signaling pathway by a downstream molecular mechanism that remains incompletely understood. In this study, we found that dual specificity phosphatase 5 (DUSP5) is a downstream target of p68, using microarray analysis, and that p68 negatively regulates DUSP5. Upregulating DUSP5 in stably expressing cell lines (U87 and LN-229) suppressed proliferation, invasion, and migration in glioma cells in vitro, consistent with the downregulation of p68. Furthermore, upregulating DUSP5 inhibited ERK phosphorylation, whereas downregulating DUSP5 rescued the level of ERK phosphorylation, indicating that DUSP5 might negatively regulate ERK signaling. Additionally, we show that DUSP5 levels were lower in high-grade glioma than in low-grade glioma. These results suggest that the p68-induced negative regulation of DUSP5 promoted invasion by glioma cells and mediated the activation of the ERK signaling pathway.
Collapse
Affiliation(s)
- Rui Wang
- Department of NeurologyThe Second Clinical College of Harbin Medical UniversityHarbinChina
| | - Hong‐Bo Bao
- Department of NeurosurgeryCancer Hospital of Harbin Medical UniversityHarbinChina
| | - Wen‐Zhong Du
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Xiao‐Feng Chen
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Huai‐Lei Liu
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Da‐Yong Han
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Li‐Gang Wang
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Jia‐Ning Wu
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Chun‐Lei Wang
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Ming‐Chun Yang
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Zhan‐Wen Liu
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Na Zhang
- Department of Laboratory DiagnosticsThe First Clinical College of Harbin Medical UniversityHarbinChina
| | - Lei Teng
- Department of NeurosurgeryThe First Clinical College of Harbin Medical UniversityHarbinChina
| |
Collapse
|
10
|
Xing Z, Ma WK, Tran EJ. The DDX5/Dbp2 subfamily of DEAD-box RNA helicases. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 10:e1519. [PMID: 30506978 DOI: 10.1002/wrna.1519] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 10/26/2018] [Accepted: 11/01/2018] [Indexed: 01/05/2023]
Abstract
The mammalian DEAD-box RNA helicase DDX5, its paralog DDX17, and their orthologs in Saccharomyces cerevisiae and Drosophila melanogaster, namely Dbp2 and Rm62, define a subfamily of DEAD-box proteins. Members from this subfamily share highly conserved protein sequences and cellular functions. They are involved in multiple steps of RNA metabolism including mRNA processing, microRNA processing, ribosome biogenesis, RNA decay, and regulation of long noncoding RNA activities. The DDX5/Dbp2 subfamily is also implicated in transcription regulation, cellular signaling pathways, and energy metabolism. One emerging theme underlying the diverse cellular functions is that the DDX5/Dbp2 subfamily of DEAD-box helicases act as chaperones for complexes formed by RNA molecules and proteins (RNP) in vivo. This RNP chaperone activity governs the functions of various RNA species through their lifetime. Importantly, mammalian DDX5 and DDX17 are involved in cancer progression when overexpressed through alteration of transcription and signaling pathways, meaning that they are possible targets for cancer therapy. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.
Collapse
Affiliation(s)
- Zheng Xing
- Department of Biochemistry, Purdue University, West Lafayette, Indiana.,Purdue Center for Cancer Research, Purdue University, West Lafayette, Indiana
| | - Wai Kit Ma
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York
| | - Elizabeth J Tran
- Department of Biochemistry, Purdue University, West Lafayette, Indiana.,Purdue Center for Cancer Research, Purdue University, West Lafayette, Indiana
| |
Collapse
|
11
|
Suzuki H, Shibagaki Y, Hattori S, Matsuoka M. The proline-arginine repeat protein linked to C9-ALS/FTD causes neuronal toxicity by inhibiting the DEAD-box RNA helicase-mediated ribosome biogenesis. Cell Death Dis 2018; 9:975. [PMID: 30250194 PMCID: PMC6155127 DOI: 10.1038/s41419-018-1028-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/16/2018] [Accepted: 09/04/2018] [Indexed: 12/31/2022]
Abstract
A GGGGCC repeat expansion in the C9ORF72 gene has been identified as the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. The repeat expansion undergoes unconventional translation to produce dipeptide repeat (DPR) proteins. Although it has been reported that DPR proteins cause neurotoxicity, the underlying mechanism has not been fully elucidated. In this study, we have first confirmed that proline-arginine repeat protein (poly-PR) reduces levels of ribosomal RNA and causes neurotoxicity and found that the poly-PR-induced neurotoxicity is repressed by the acceleration of ribosomal RNA synthesis. These results suggest that the poly-PR-induced inhibition of ribosome biogenesis contributes to the poly-PR-induced neurotoxicity. We have further identified DEAD-box RNA helicases as poly-PR-binding proteins, the functions of which are inhibited by poly-PR. The enforced reduction in the expression of DEAD-box RNA helicases causes impairment of ribosome biogenesis and neuronal cell death. These results together suggest that poly-PR causes neurotoxicity by inhibiting the DEAD-box RNA helicase-mediated ribosome biogenesis.
Collapse
Affiliation(s)
- Hiroaki Suzuki
- Department of Pharmacology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan
| | - Yoshio Shibagaki
- Division of Biochemistry, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo, 108-8641, Japan
| | - Seisuke Hattori
- Division of Biochemistry, School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo, 108-8641, Japan
| | - Masaaki Matsuoka
- Department of Pharmacology, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan.
- Department of Dermatological Neuroscience, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan.
| |
Collapse
|
12
|
Xue Y, Jia X, Li L, Dong X, Ling J, Yuan J, Li Q. DDX5 promotes hepatocellular carcinoma tumorigenesis via Akt signaling pathway. Biochem Biophys Res Commun 2018; 503:2885-2891. [PMID: 30119889 DOI: 10.1016/j.bbrc.2018.08.063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Accepted: 08/07/2018] [Indexed: 02/07/2023]
Abstract
The DEAD-box-protein DDX5 is an ATP-dependent RNA helicase and also acts as co-activator that contributes to progression and metastasis of various tumours. However, its expression as well as prognostic roles of DDX5 in hepatocellular carcinoma (HCC) remain elusive. In this study, we investigated clinical significance and biological functions of DDX5 in HCC. Our results suggested that DDX5 showed overexpression at both transcriptional and translational levels in HCC tissues compared with adjacent normal tissues. Moreover, DDX5 expression was demonstrated to be correlated with tumor size (p < 0.001), N stage (p = 0.013), M stage (p = 0.006), tumor differentiation (p < 0.001) and American Joint Committee on Cancer (AJCC) stage (p = 0.001). Simultaneously, high DDX5 expression was found to be significantly correlated to worse outcome including Disease free survival (DFS) (p = 0.016) and overall survival (OS) (p = 0.032) according to Kaplan-Meier survival analysis. In vitro studies, it suggested that knockdown of DDX5 suppressed HCC cells migration, invasion and epithelial -to- mesenchymal transition (EMT) process. Depletion of DDX5 could promote HCC cells growth. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that PI3K/Akt signaling pathway obtained the highest enrichment. Furthermore, we found that knockdown of DDX5 decreased Akt as well as p-Akt (S473) expressions. Collectively, these findings suggested that DDX5 facilitated HCC cells growth via Akt signaling pathway. DDX5 played a crucial role in HCC proliferation and tumorigenesis and may be a novel prognostic marker and potential therapeutic target for HCC.
Collapse
Affiliation(s)
- Ying Xue
- Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou, Shanghai, 200080, China
| | - Xuebing Jia
- Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou, Shanghai, 200080, China
| | - Lei Li
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Xiao Dong
- Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou, Shanghai, 200080, China
| | - Jing Ling
- Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou, Shanghai, 200080, China
| | - Jian Yuan
- Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine, Shanghai, 200120, China; Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine, Shanghai, 200120, China; Department of Oncology, Mayo Clinic, Rochester, MN, 55905, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA
| | - Qi Li
- Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou, Shanghai, 200080, China.
| |
Collapse
|
13
|
Cheng W, Chen G, Jia H, He X, Jing Z. DDX5 RNA Helicases: Emerging Roles in Viral Infection. Int J Mol Sci 2018; 19:ijms19041122. [PMID: 29642538 PMCID: PMC5979547 DOI: 10.3390/ijms19041122] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 03/29/2018] [Accepted: 04/02/2018] [Indexed: 02/07/2023] Open
Abstract
Asp-Glu-Ala-Asp (DEAD)-box polypeptide 5 (DDX5), also called p68, is a prototypical member of the large ATP-dependent RNA helicases family and is known to participate in all aspects of RNA metabolism ranging from transcription to translation, RNA decay, and miRNA processing. The roles of DDX5 in cell cycle regulation, tumorigenesis, apoptosis, cancer development, adipogenesis, Wnt-β-catenin signaling, and viral infection have been established. Several RNA viruses have been reported to hijack DDX5 to facilitate various steps of their replication cycles. Furthermore, DDX5 can be bounded by the viral proteins of some viruses with unknown functions. Interestingly, an antiviral function of DDX5 has been reported during hepatitis B virus and myxoma virus infection. Thus, the precise roles of this apparently multifaceted protein remain largely obscure. Here, we provide a rapid and critical overview of the structure and functions of DDX5 with a particular emphasis on its role during virus infection.
Collapse
Affiliation(s)
- Wenyu Cheng
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Agriculture Ministry, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, Gansu, China.
| | - Guohua Chen
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Agriculture Ministry, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, Gansu, China.
| | - Huaijie Jia
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Agriculture Ministry, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, Gansu, China.
| | - Xiaobing He
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Agriculture Ministry, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, Gansu, China.
| | - Zhizhong Jing
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Public Health of Agriculture Ministry, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, Gansu, China.
| |
Collapse
|
14
|
Auboeuf D. Alternative mRNA processing sites decrease genetic variability while increasing functional diversity. Transcription 2017; 9:75-87. [PMID: 29099315 PMCID: PMC5834221 DOI: 10.1080/21541264.2017.1373891] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Recent large-scale RNA sequencing efforts have revealed the extensive diversity of mRNA molecules produced from most eukaryotic coding genes, which arises from the usage of alternative, cryptic or non-canonical splicing and intronic polyadenylation sites. The prevailing view regarding the tremendous diversity of coding gene transcripts is that mRNA processing is a flexible and more-or-less noisy process leading to a diversity of proteins on which natural selection can act depending on protein-mediated cellular functions. However, this concept raises two main questions. First, do alternative mRNA processing pathways have a role other than generating mRNA and protein diversity? Second, is the cellular function of mRNA variants restricted to the biogenesis of functional protein isoforms? Here, I propose that the co-transcriptional use of alternative mRNA processing sites allows first, the resolution of co-transcriptional biophysical constraints that may otherwise result in DNA instability, and second, increases the diversity of cellular functions of mRNAs in a manner that is not restricted to protein synthesis.
Collapse
Affiliation(s)
- Didier Auboeuf
- a Univ Lyon, ENS de Lyon, Univ Claude Bernard, CNRS UMR 5239, INSERM U1210, Laboratory of Biology and Modelling of the Cell , 46 Allée d'Italie Site Jacques Monod, Lyon , France
| |
Collapse
|
15
|
Xing Z, Wang S, Tran EJ. Characterization of the mammalian DEAD-box protein DDX5 reveals functional conservation with S. cerevisiae ortholog Dbp2 in transcriptional control and glucose metabolism. RNA (NEW YORK, N.Y.) 2017; 23:1125-1138. [PMID: 28411202 PMCID: PMC5473146 DOI: 10.1261/rna.060335.116] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 04/10/2017] [Indexed: 05/09/2023]
Abstract
DEAD-box proteins are a class of nonprocessive RNA helicases that dynamically modulate the structure of RNA and ribonucleoprotein complexes (RNPs). However, the precise roles of individual members are not well understood. Work from our laboratory revealed that the DEAD-box protein Dbp2 in Saccharomyces cerevisiae is an active RNA helicase in vitro that functions in transcription by promoting mRNP assembly, repressing cryptic transcription initiation, and regulating long noncoding RNA activity. Interestingly, Dbp2 is also linked to glucose sensing and hexose transporter gene expression. DDX5 is the mammalian ortholog of Dbp2 that has been implicated in cancer and metabolic syndrome, suggesting that the role of Dbp2 and DDX5 in glucose metabolic regulation is conserved. Herein, we present a refined biochemical and biological comparison of yeast Dbp2 and human DDX5 enzymes. We find that human DDX5 possesses a 10-fold higher unwinding activity than Dbp2, which is partially due to the presence of a mammalian/avian specific C-terminal extension. Interestingly, ectopic expression of DDX5 rescues the cold sensitivity, cryptic initiation defects, and impaired glucose import in dbp2Δ cells, suggesting functional conservation. Consistently, we show that DDX5 promotes glucose uptake and glycolysis in mouse AML12 hepatocyte cells, suggesting that mammalian DDX5 and S. cerevisiae Dbp2 share conserved roles in cellular metabolism.
Collapse
Affiliation(s)
- Zheng Xing
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47906, USA
| | - Siwen Wang
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47906, USA
| | - Elizabeth J Tran
- Department of Biochemistry, Purdue University, West Lafayette, Indiana 47906, USA
- Purdue Center for Cancer Research, Purdue University, West Lafayette, Indiana 47906, USA
| |
Collapse
|
16
|
Huang CH, Chen N, Huang CX, Zhang B, Wu M, He L, Liu H, Tang R, Wang WM, Wang HL. Involvement of the miR-462/731 cluster in hypoxia response in Megalobrama amblycephala. FISH PHYSIOLOGY AND BIOCHEMISTRY 2017; 43:863-873. [PMID: 28280952 DOI: 10.1007/s10695-017-0341-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 01/04/2017] [Indexed: 05/20/2023]
Abstract
MicroRNAs (miRNAs) are non-coding small RNAs showing both evolutionarily conserved and unique features and are involved in nearly all biological processes. In the present study, the role played by miR-462/731 cluster miRNAs in hypoxia response in Megalobrama amblycephala, an important freshwater fish, was investigated. The M. amblycephala miR-462/731 cluster locus and their 5' flanking sequences were sequenced and analyzed. In M. amblycephala and other teleost fish species, the mature sequences of miR-462 and miR-731 were identical and hypoxia-responsive elements (HREs) were identified upstream of the miR-462/731 loci. The two miRNAs were significantly induced in the liver, spleen, gill, muscle, and brain after hypoxia treatment. The expression of both miRNAs was also upregulated in cells that received treatment which mimicked hypoxia. Furthermore, reporter assay revealed that M. amblycephala HREs can be activated by hypoxia. Taken together, the 462/731 cluster may play a role in the regulation of the hypoxia response in M. amblycephala.
Collapse
Affiliation(s)
- Cui-Hong Huang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Nan Chen
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Chun-Xiao Huang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Bao Zhang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Meng Wu
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Lei He
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Hong Liu
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, 430070, Wuhan, People's Republic of China
- Hubei Provincial Engineering Laboratory for Pond Aquaculture, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Rong Tang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, 430070, Wuhan, People's Republic of China
- Hubei Provincial Engineering Laboratory for Pond Aquaculture, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Wei-Min Wang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
- Hubei Provincial Engineering Laboratory for Pond Aquaculture, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China
| | - Huan-Ling Wang
- Key Lab of Freshwater Animal Breeding, Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China.
- Freshwater Aquaculture Collaborative Innovation Center of Hubei Province, 430070, Wuhan, People's Republic of China.
- Hubei Provincial Engineering Laboratory for Pond Aquaculture, College of Fishery, Huazhong Agricultural University, 430070, Wuhan, People's Republic of China.
| |
Collapse
|
17
|
The multiple functions of RNA helicases as drivers and regulators of gene expression. Nat Rev Mol Cell Biol 2016; 17:426-38. [PMID: 27251421 DOI: 10.1038/nrm.2016.50] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
RNA helicases comprise the largest family of enzymes involved in the metabolism of mRNAs, the processing and fate of which rely on their packaging into messenger ribonucleoprotein particles (mRNPs). In this Review, we describe how the capacity of some RNA helicases to either remodel or lock the composition of mRNP complexes underlies their pleiotropic functions at different steps of the gene expression process. We illustrate the roles of RNA helicases in coordinating gene expression steps and programmes, and propose that RNA helicases function as molecular drivers and guides of the progression of their mRNA substrates from one RNA-processing factory to another, to a productive mRNA pool that leads to protein synthesis or to unproductive mRNA pools that are stored or degraded.
Collapse
|
18
|
Recruitment, Duplex Unwinding and Protein-Mediated Inhibition of the Dead-Box RNA Helicase Dbp2 at Actively Transcribed Chromatin. J Mol Biol 2016; 428:1091-1106. [PMID: 26876600 DOI: 10.1016/j.jmb.2016.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 01/26/2016] [Accepted: 02/02/2016] [Indexed: 02/07/2023]
Abstract
RNA helicases play fundamental roles in modulating RNA structures and facilitating RNA-protein (RNP) complex assembly in vivo. Previously, our laboratory demonstrated that the DEAD-box RNA helicase Dbp2 in Saccharomyces cerevisiae is required to promote efficient assembly of the co-transcriptionally associated mRNA-binding proteins Yra1, Nab2, and Mex67 onto poly(A)(+)RNA. We also found that Yra1 associates directly with Dbp2 and functions as an inhibitor of Dbp2-dependent duplex unwinding, suggestive of a cycle of unwinding and inhibition by Dbp2. To test this, we undertook a series of experiments to shed light on the order of events for Dbp2 in co-transcriptional mRNP assembly. We now show that Dbp2 is recruited to chromatin via RNA and forms a large, RNA-dependent complex with Yra1 and Mex67. Moreover, single-molecule fluorescence resonance energy transfer and bulk biochemical assays show that Yra1 inhibits unwinding in a concentration-dependent manner by preventing the association of Dbp2 with single-stranded RNA. This inhibition prevents over-accumulation of Dbp2 on mRNA and stabilization of a subset of RNA polymerase II transcripts. We propose a model whereby Yra1 terminates a cycle of mRNP assembly by Dbp2.
Collapse
|
19
|
The expression of RNA helicase DDX5 is transcriptionally upregulated by calcitriol through a vitamin D response element in the proximal promoter in SiHa cervical cells. Mol Cell Biochem 2015; 410:65-73. [DOI: 10.1007/s11010-015-2538-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/18/2015] [Indexed: 12/22/2022]
|
20
|
Moy RH, Cole BS, Yasunaga A, Gold B, Shankarling G, Varble A, Molleston JM, tenOever BR, Lynch KW, Cherry S. Stem-loop recognition by DDX17 facilitates miRNA processing and antiviral defense. Cell 2014; 158:764-777. [PMID: 25126784 DOI: 10.1016/j.cell.2014.06.023] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 05/20/2014] [Accepted: 06/06/2014] [Indexed: 12/18/2022]
Abstract
DEAD-box helicases play essential roles in RNA metabolism across species, but emerging data suggest that they have additional functions in immunity. Through RNAi screening, we identify an evolutionarily conserved and interferon-independent role for the DEAD-box helicase DDX17 in restricting Rift Valley fever virus (RVFV), a mosquito-transmitted virus in the bunyavirus family that causes severe morbidity and mortality in humans and livestock. Loss of Drosophila DDX17 (Rm62) in cells and flies enhanced RVFV infection. Similarly, depletion of DDX17 but not the related helicase DDX5 increased RVFV replication in human cells. Using crosslinking immunoprecipitation high-throughput sequencing (CLIP-seq), we show that DDX17 binds the stem loops of host pri-miRNA to facilitate their processing and also an essential stem loop in bunyaviral RNA to restrict infection. Thus, DDX17 has dual roles in the recognition of stem loops: in the nucleus for endogenous microRNA (miRNA) biogenesis and in the cytoplasm for surveillance against structured non-self-elements.
Collapse
Affiliation(s)
- Ryan H Moy
- Department of Microbiology, Penn Genome Frontiers Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Brian S Cole
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ari Yasunaga
- Department of Microbiology, Penn Genome Frontiers Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Beth Gold
- Department of Microbiology, Penn Genome Frontiers Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ganesh Shankarling
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Andrew Varble
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Jerome M Molleston
- Department of Microbiology, Penn Genome Frontiers Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Benjamin R tenOever
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kristen W Lynch
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sara Cherry
- Department of Microbiology, Penn Genome Frontiers Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
21
|
Zhao S, Ge X, Wang X, Liu A, Guo X, Zhou L, Yu K, Yang H. The DEAD-box RNA helicase 5 positively regulates the replication of porcine reproductive and respiratory syndrome virus by interacting with viral Nsp9 in vitro. Virus Res 2014; 195:217-24. [PMID: 25449571 PMCID: PMC7114378 DOI: 10.1016/j.virusres.2014.10.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 10/24/2014] [Accepted: 10/27/2014] [Indexed: 10/27/2022]
Abstract
The nonstructural protein 9 (Nsp9) of porcine reproductive and respiratory syndrome virus (PRRSV) has been recognized to play important roles in viral replication. The present study first screened that the DEAD-box RNA helicase 5 (DDX5) was a cellular protein interacting with the Nsp9 of PRRSV by a yeast two-hybrid method in a pulmonary alveolar macrophages (PAMs) cDNA library. Next, DDX5 was shown to interact with viral Nsp9 in the co-transfected HEK293 cells with the DDX5- and Nsp9-expressing plasmids, and the interaction between endogenous DDX5 and Nsp9 was also confirmed in MARC-145 cells infected with the Nsp9-expressing lentiviruses. Then, the interacting domains between DDX5 and Nsp9 were determined to be the DEXDc and HELICc domains in DDX5 and the RdRp domain in Nsp9, respectively. Moreover, in the HEK293 cells, MARC-145 cells and PAM cell lines co-transfected with the DDX5- and Nsp9-expressing plasmids, Nsp9 was shown to co-localize with DDX5 in the cytoplasm with a perinuclear pattern, and meanwhile in PRRSV-infected MARC-145 cells and PAMs, endogenous DDX5 was also found to co-localize with Nsp9. Finally, silencing the DDX5 gene in MARC-145 cells significantly impacted the replication of PRRSV, and while the over-expression of DDX5 could slightly enhance viral replication. These findings indicate that DDX5 positively regulates the replication of PRRSV via its interaction with viral Nsp9 in vitro.
Collapse
Affiliation(s)
- Shuangcheng Zhao
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Xinna Ge
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Xiaolong Wang
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Aijing Liu
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Xin Guo
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Lei Zhou
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Kangzhen Yu
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China; The Ministry of Agriculture of the People's Republic of China, Beijing 100026, People's Republic of China
| | - Hanchun Yang
- Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing 100193, People's Republic of China.
| |
Collapse
|
22
|
Dardenne E, Polay Espinoza M, Fattet L, Germann S, Lambert MP, Neil H, Zonta E, Mortada H, Gratadou L, Deygas M, Chakrama FZ, Samaan S, Desmet FO, Tranchevent LC, Dutertre M, Rimokh R, Bourgeois CF, Auboeuf D. RNA helicases DDX5 and DDX17 dynamically orchestrate transcription, miRNA, and splicing programs in cell differentiation. Cell Rep 2014; 7:1900-13. [PMID: 24910439 DOI: 10.1016/j.celrep.2014.05.010] [Citation(s) in RCA: 145] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 04/08/2014] [Accepted: 05/05/2014] [Indexed: 02/07/2023] Open
Abstract
The RNA helicases DDX5 and DDX17 are members of a large family of highly conserved proteins that are involved in gene-expression regulation; however, their in vivo targets and activities in biological processes such as cell differentiation, which requires reprogramming of gene-expression programs at multiple levels, are not well characterized. Here, we uncovered a mechanism by which DDX5 and DDX17 cooperate with heterogeneous nuclear ribonucleoprotein (hnRNP) H/F splicing factors to define epithelial- and myoblast-specific splicing subprograms. We then observed that downregulation of DDX5 and DDX17 protein expression during myogenesis and epithelial-to-mesenchymal transdifferentiation contributes to the switching of splicing programs during these processes. Remarkably, this downregulation is mediated by the production of miRNAs induced upon differentiation in a DDX5/DDX17-dependent manner. Since DDX5 and DDX17 also function as coregulators of master transcriptional regulators of differentiation, we propose to name these proteins "master orchestrators" of differentiation that dynamically orchestrate several layers of gene expression.
Collapse
Affiliation(s)
- Etienne Dardenne
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Micaela Polay Espinoza
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Laurent Fattet
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Sophie Germann
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Marie-Pierre Lambert
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Helen Neil
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Eleonora Zonta
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Hussein Mortada
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Lise Gratadou
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Mathieu Deygas
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Fatima Zahra Chakrama
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Samaan Samaan
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - François-Olivier Desmet
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Léon-Charles Tranchevent
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Martin Dutertre
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Ruth Rimokh
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France
| | - Cyril F Bourgeois
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France.
| | - Didier Auboeuf
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France; Université Claude Bernard Lyon 1, 69008 Lyon, France; Centre Léon Bérard, 69008 Lyon, France.
| |
Collapse
|
23
|
Nilsson EM, Fainberg HP, Choong SS, Giles TC, Sells J, May S, Stansfield FJ, Allen WR, Emes RD, Mostyn A, Mongan NP, Yon L. Molecular characterization of adipose tissue in the African elephant (Loxodonta africana). PLoS One 2014; 9:e91717. [PMID: 24633017 PMCID: PMC3954733 DOI: 10.1371/journal.pone.0091717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 02/14/2014] [Indexed: 01/01/2023] Open
Abstract
Adipose tissue (AT) is a dynamic and flexible organ with regulatory roles in physiological functions including metabolism, reproduction and inflammation; secreted adipokines, including leptin, and fatty acids facilitate many of these roles. The African elephant (Loxodonta africana) is experiencing serious challenges to optimal reproduction in captivity. The physiological and molecular basis of this impaired fertility remains unknown. AT production of leptin is a crucial molecular link between nutritional status, adiposity and fertility in many species. We propose that leptin has a similar function in the African elephant. African elephant visceral and subcutaneous adipose tissue (AT) was obtained from both sexes and a range of ages including females with known pregnancy status. RNA was extracted and histological sections created and analyzed by microarray, PCR and immunohistochemistry respectively. Gas-chromatography was used to determine the fatty acid composition of AT. Microarray expression profiling was used to compare gene expression profiles of AT from pre-pubertal versus reproductively competent adult African elephants. This study demonstrates, for the first time, leptin mRNA and protein expression in African elephant AT. The derived protein sequence of the elephant leptin protein was exploited to determine its relationship within the class I helical cytokine superfamily, which indicates that elephant leptin is most closely related to the leptin orthologs of Oryctolagus cuniculus (European rabbit), Lepus oiostolus (woolly hare), and members of the Ochotonidae (Pika). Immunohistological analysis identified considerable leptin staining within the cytoplasm of adipocytes. Significant differences in fatty acid profiles between pregnant and non-pregnant animals were revealed, most notably a reduction in both linoleic and α linoleic acid in pregnant animals. This report forms the basis for future studies to address the effect of nutrient composition and body condition on reproduction in captive and wild elephants.
Collapse
Affiliation(s)
- Emeli M. Nilsson
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Hernan P. Fainberg
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Siew S. Choong
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Thomas C. Giles
- Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington, United Kingdom
| | - James Sells
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Sean May
- The Nottingham Arabidopsis Stock Centre, Division of Plant Sciences, University of Nottingham, Sutton Bonington, United Kingdom
| | - Fiona J. Stansfield
- The Elephant Research and Conservation Unit, Savé Valley Conservancy, Harare, Zimbabwe
| | - William R. Allen
- The Paul Mellon Laboratory, “Brunswick,” Woodditton Road, Newmarket, Suffolk, United Kingdom
| | - Richard D. Emes
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
- Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington, United Kingdom
| | - Alison Mostyn
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Nigel P. Mongan
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| | - Lisa Yon
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, Sutton Bonington Campus, University of Nottingham, Sutton Bonington, United Kingdom
| |
Collapse
|
24
|
Samaan S, Tranchevent LC, Dardenne E, Polay Espinoza M, Zonta E, Germann S, Gratadou L, Dutertre M, Auboeuf D. The Ddx5 and Ddx17 RNA helicases are cornerstones in the complex regulatory array of steroid hormone-signaling pathways. Nucleic Acids Res 2013; 42:2197-207. [PMID: 24275493 PMCID: PMC3936752 DOI: 10.1093/nar/gkt1216] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Estrogen and androgen receptors (ER and AR) play key roles in breast and prostate cancers, respectively, where they regulate the transcription of large arrays of genes. The activities of ER and AR are controlled by large networks of protein kinases and transcriptional coregulators, including Ddx5 and its highly related paralog Ddx17. The Ddx5 and Ddx17 RNA helicases are also splicing regulators. Here, we report that Ddx5 and Ddx17 are master regulators of the estrogen- and androgen-signaling pathways by controlling transcription and splicing both upstream and downstream of the receptors. First, Ddx5 and Ddx17 are required downstream of ER and AR for the transcriptional and splicing regulation of a large number of steroid hormone target genes. Second, Ddx5 and Ddx17 act upstream of ER and AR by controlling the expression, at the splicing level, of several key regulators of ER and AR activities. Of particular interest, we demonstrate that Ddx5 and Ddx17 control alternative splicing of the GSK3β kinase, which impacts on both ER and AR protein stability. We also provide a freely available online resource which gives information regarding splicing variants of genes involved in the estrogen- and androgen-signaling pathways.
Collapse
Affiliation(s)
- Samaan Samaan
- Université de Paris Diderot-Paris 7, F-75013 Paris, France, Inserm U1052, F-69008 Lyon, France, CNRS UMR5286, F-69008 Lyon, France, Centre de Recherche en Cancérologie de Lyon, 69008 Lyon, France and Université de Lyon 1, F-69100 Villeurbanne, France
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Sette C. Alternative splicing programs in prostate cancer. Int J Cell Biol 2013; 2013:458727. [PMID: 23983695 PMCID: PMC3747374 DOI: 10.1155/2013/458727] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/11/2013] [Indexed: 12/31/2022] Open
Abstract
Prostate cancer (PCa) remains one of the most frequent causes of death for cancer in the male population. Although the initial antiandrogenic therapies are efficacious, PCa often evolves into a hormone-resistant, incurable disease. The genetic and phenotypic heterogeneity of this type of cancer renders its diagnosis and cure particularly challenging. Mounting evidence indicates that alternative splicing, the process that allows production of multiple mRNA variants from each gene, contributes to the heterogeneity of the disease. Key genes for the biology of normal and neoplastic prostate cells, such as those encoding for the androgen receptor and cyclin D1, are alternatively spliced to yield protein isoforms with different or even opposing functions. This review illustrates some examples of genes whose alternative splicing regulation is relevant to PCa biology and discusses the possibility to exploit alternative splicing regulation as a novel tool for prognosis, diagnosis, and therapeutic approaches to PCa.
Collapse
Affiliation(s)
- Claudio Sette
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata,” 00133 Rome, Italy
- Laboratory of Neuroembryology, Fondazione Santa Lucia IRCCS, 00143 Rome, Italy
| |
Collapse
|
26
|
Geißler V, Altmeyer S, Stein B, Uhlmann-Schiffler H, Stahl H. The RNA helicase Ddx5/p68 binds to hUpf3 and enhances NMD of Ddx17/p72 and Smg5 mRNA. Nucleic Acids Res 2013; 41:7875-88. [PMID: 23788676 PMCID: PMC3763533 DOI: 10.1093/nar/gkt538] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Non-sense-mediated mRNA decay (NMD) is a mechanism of translation-dependent mRNA surveillance in eukaryotes: it degrades mRNAs with premature termination codons (PTCs) and contributes to cellular homeostasis by downregulating a number of physiologically important mRNAs. In the NMD pathway, Upf proteins, a set of conserved factors of which Upf1 is the central regulator, recruit decay enzymes to promote RNA cleavage. In mammals, the degradation of PTC-containing mRNAs is triggered by the exon–junction complex (EJC) through binding of its constituents Upf2 and Upf3 to Upf1. The complex formed eventually induces translational repression and recruitment of decay enzymes. Mechanisms by which physiological mRNAs are targeted by the NMD machinery in the absence of an EJC have been described but still are discussed controversially. Here, we report that the DEAD box proteins Ddx5/p68 and its paralog Ddx17/p72 also bind the Upf complex by physical interaction with Upf3, thereby interfering with the binding of EJC. By activating the NMD machinery, Ddx5 is shown to regulate the expression of its own, Ddx17 and Smg5 mRNAs. For NMD triggering, the adenosine triphosphate-binding activity of Ddx5 and the 3′-untranslated region of substrate mRNAs are essential.
Collapse
Affiliation(s)
- Verena Geißler
- Department of Medical Biochemistry and Molecular Biology, University of Saarland, Medical Center, Building 45, 66421 Homburg, Germany
| | | | | | | | | |
Collapse
|
27
|
Ma WK, Cloutier SC, Tran EJ. The DEAD-box protein Dbp2 functions with the RNA-binding protein Yra1 to promote mRNP assembly. J Mol Biol 2013; 425:3824-38. [PMID: 23721653 DOI: 10.1016/j.jmb.2013.05.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 05/01/2013] [Accepted: 05/18/2013] [Indexed: 11/25/2022]
Abstract
Eukaryotic gene expression involves numerous biochemical steps that are dependent on RNA structure and ribonucleoprotein (RNP) complex formation. The DEAD-box class of RNA helicases plays fundamental roles in formation of RNA and RNP structure in every aspect of RNA metabolism. In an effort to explore the diversity of biological roles for DEAD-box proteins, our laboratory recently demonstrated that the DEAD-box protein Dbp2 associates with actively transcribing genes and is required for normal gene expression in Saccharomyces cerevisiae. We now provide evidence that Dbp2 interacts genetically and physically with the mRNA export factor Yra1. In addition, we find that Dbp2 is required for in vivo assembly of mRNA-binding proteins Yra1, Nab2, and Mex67 onto poly(A)+ RNA. Strikingly, we also show that Dbp2 is an efficient RNA helicase in vitro and that Yra1 decreases the efficiency of ATP-dependent duplex unwinding. We provide a model whereby messenger ribonucleoprotein (mRNP) assembly requires Dbp2 unwinding activity and once the mRNP is properly assembled, inhibition by Yra1 prevents further rearrangements. Both Yra1 and Dbp2 are conserved in multicellular eukaryotes, suggesting that this constitutes a broadly conserved mechanism for stepwise assembly of mature mRNPs in the nucleus.
Collapse
Affiliation(s)
- Wai Kit Ma
- Department of Biochemistry, Purdue University, BCHM 305, 175 South University Street, West Lafayette, IN 47907-2063, USA; Purdue University Center for Cancer Research, Purdue University, Hansen Life Sciences Research Building, Room 141, 201 South University Street, West Lafayette, IN 47907-2064, USA
| | | | | |
Collapse
|
28
|
Robert F, Pelletier J. Perturbations of RNA helicases in cancer. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:333-49. [PMID: 23658027 DOI: 10.1002/wrna.1163] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Helicases are implicated in most stages of the gene expression pathway, ranging from DNA replication, RNA transcription, splicing, RNA transport, ribosome biogenesis, mRNA translation, RNA storage and decay. These enzymes utilize energy derived from nucleotide triphosphate hydrolysis to remodel ribonucleoprotein complexes, RNA, or DNA and in this manner affect the information content or output of RNA. Several RNA helicases have been implicated in the oncogenic process--either through altered expression levels, mutations, or due to their role in pathways required for tumor initiation, progression, maintenance, or chemosensitivity. The purpose of this review is to highlight those RNA helicases for which there is significant evidence implicating them in cancer biology.
Collapse
Affiliation(s)
- Francis Robert
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | | |
Collapse
|