1
|
Nicchitta CV. An emerging role for the endoplasmic reticulum in stress granule biogenesis. Semin Cell Dev Biol 2024; 156:160-166. [PMID: 36202692 PMCID: PMC10208384 DOI: 10.1016/j.semcdb.2022.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/07/2022] [Accepted: 09/26/2022] [Indexed: 11/07/2022]
Abstract
Stress granules (SGs), structurally dynamic, optically resolvable, macromolecular assemblies of mRNAs, RNA binding proteins (RBPs), translation factors, ribosomal subunits, as well as other interacting proteins, assemble in response to cell stress conditions that elicit phosphorylation of eukaryotic initiation factor 2α (eIF2α) and consequently, the inactivation of translation initiation. SG biology is conserved throughout eukaryotes and has recently been linked to the pathological sequelae of neurodegenerative disorders, cancer biology, and viral infection. Substantial insights into mechanisms of SG biogenesis, and more broadly the phenomenon of biological liquid-liquid phase separation (LLPS), have been aided by detailed proteomic and transcriptomic studies as well as in vitro reconstitution approaches. A particularly interesting and largely unexplored element of SG biology is the cell biological context of SG biogenesis, including its subcellular organization and more recently, evidence that the endoplasmic reticulum (ER) membrane may serve important functions in RNA granule biology generally and SG biogenesis specifically. A central role for the ER in SG biogenesis is discussed and a hypothesis linking SG formation on the ER to the trafficking, localization and de novo translation of newly exported mRNAs is presented.
Collapse
|
2
|
Abbas H, Derkaoui DK, Jeammet L, Adicéam E, Tiollier J, Sicard H, Braun T, Poyet JL. Apoptosis Inhibitor 5: A Multifaceted Regulator of Cell Fate. Biomolecules 2024; 14:136. [PMID: 38275765 PMCID: PMC10813780 DOI: 10.3390/biom14010136] [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: 12/19/2023] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
Apoptosis, or programmed cell death, is a fundamental process that maintains tissue homeostasis, eliminates damaged or infected cells, and plays a crucial role in various biological phenomena. The deregulation of apoptosis is involved in many human diseases, including cancer. One of the emerging players in the intricate regulatory network of apoptosis is apoptosis inhibitor 5 (API5), also called AAC-11 (anti-apoptosis clone 11) or FIF (fibroblast growth factor-2 interacting factor). While it may not have yet the same level of notoriety as some other cancer-associated proteins, API5 has garnered increasing attention in the cancer field in recent years, as elevated API5 levels are often associated with aggressive tumor behavior, resistance to therapy, and poor patient prognosis. This review aims to shed light on the multifaceted functions and regulatory mechanisms of API5 in cell fate decisions as well as its interest as therapeutic target in cancer.
Collapse
Affiliation(s)
- Hafsia Abbas
- Université Oran 1, Ahmed Ben Bella, Oran 31000, Algeria; (H.A.); (D.K.D.)
| | | | - Louise Jeammet
- Jalon Therapeutics, 75010 Paris, France; (L.J.); (J.T.); (H.S.)
| | - Emilie Adicéam
- Jalon Therapeutics, 75010 Paris, France; (L.J.); (J.T.); (H.S.)
| | - Jérôme Tiollier
- Jalon Therapeutics, 75010 Paris, France; (L.J.); (J.T.); (H.S.)
| | - Hélène Sicard
- Jalon Therapeutics, 75010 Paris, France; (L.J.); (J.T.); (H.S.)
| | - Thorsten Braun
- Laboratoire de Transfert des Leucémies, EA3518, Institut de Recherche Saint Louis, Hôpital Saint Louis, Université de Paris, 75010 Paris, France;
- AP-HP, Service d’Hématologie Clinique, Hôpital Avicenne, Université Paris XIII, 93000 Bobigny, France
- OPALE Carnot Institute, The Organization for Partnerships in Leukemia, Hôpital Saint-Louis, 75010 Paris, France
| | - Jean-Luc Poyet
- INSERM UMRS976, Institut de Recherche Saint Louis, Hôpital Saint Louis, 75010 Paris, France
- Université Paris Cité, 75015 Paris, France
| |
Collapse
|
3
|
Sharma M, Mason AC, Dawson TR, Wente SR. Phosphorylation impacts GLE1 nuclear localization and association with DDX1. Adv Biol Regul 2023; 90:100990. [PMID: 37801910 DOI: 10.1016/j.jbior.2023.100990] [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: 09/14/2023] [Accepted: 09/25/2023] [Indexed: 10/08/2023]
Abstract
Gle1 regulates gene expression at multiple steps from transcription to mRNA export to translation under stressed and non-stressed conditions. To better understand Gle1 function in stressed human cells, specific antibodies were generated that recognized the phosphorylation of threonine residue 102 (T102) in Gle1. A series of in vitro kinase assays indicated that T102 phosphorylation serves as a priming event for further phosphorylation in Gle1's N-terminal low complexity cluster. Indirect immunofluorescence microscopy with the anti-Gle1-pT102 antibodies revealed that basally phosphorylated Gle1 was pre-dominantly nuclear with punctate distribution; however, under sodium arsenite-induced stress, more cytoplasmic localization was detected. Immunoprecipitation with the anti-Gle1-pT102 antibody resulted in co-isolation of Gle1-pT102 with the DEAD-box protein DDX1 in a phosphatase sensitive manner. This suggested Gle1 phosphorylation might be linked to its role in regulating DDX1 during transcription termination. Notably, whereas the total Gle1-DDX1 association was decreased when Gle1 nucleocytoplasmic shuttling was disrupted, co-isolation of Gle1-pT102 and DDX1 increased under the same conditions. Taken together, these studies demonstrated that Gle1 phosphorylation impacts its cellular distribution and potentially drives nuclear Gle1 functions in transcription termination. We propose a model wherein phosphorylation of Gle1 either reduces its nucleocytoplasmic shuttling capacity or increases its binding affinity with nuclear interaction partners.
Collapse
Affiliation(s)
- Manisha Sharma
- Department of Cell and Development Biology, School of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Aaron C Mason
- Department of Cell and Development Biology, School of Medicine, Vanderbilt University, Nashville, TN, USA
| | - T Renee Dawson
- Department of Cell and Development Biology, School of Medicine, Vanderbilt University, Nashville, TN, USA
| | - Susan R Wente
- Department of Biology, and Biochemistry, Wake Forest University, Winston-Salem, NC, USA
| |
Collapse
|
4
|
Guo J, Zhu Y, Ma X, Shang G, Liu B, Zhang K. Virus Infection and mRNA Nuclear Export. Int J Mol Sci 2023; 24:12593. [PMID: 37628773 PMCID: PMC10454920 DOI: 10.3390/ijms241612593] [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: 04/21/2023] [Revised: 07/29/2023] [Accepted: 08/03/2023] [Indexed: 08/27/2023] Open
Abstract
Gene expression in eukaryotes begins with transcription in the nucleus, followed by the synthesis of messenger RNA (mRNA), which is then exported to the cytoplasm for its translation into proteins. Along with transcription and translation, mRNA export through the nuclear pore complex (NPC) is an essential regulatory step in eukaryotic gene expression. Multiple factors regulate mRNA export and hence gene expression. Interestingly, proteins from certain types of viruses interact with these factors in infected cells, and such an interaction interferes with the mRNA export of the host cell in favor of viral RNA export. Thus, these viruses hijack the host mRNA nuclear export mechanism, leading to a reduction in host gene expression and the downregulation of immune/antiviral responses. On the other hand, the viral mRNAs successfully evade the host surveillance system and are efficiently exported from the nucleus to the cytoplasm for translation, which enables the continuation of the virus life cycle. Here, we present this review to summarize the mechanisms by which viruses suppress host mRNA nuclear export during infection, as well as the key strategies that viruses use to facilitate their mRNA nuclear export. These studies have revealed new potential antivirals that may be used to inhibit viral mRNA transport and enhance host mRNA nuclear export, thereby promoting host gene expression and immune responses.
Collapse
Affiliation(s)
- Jiayin Guo
- University of Chinese Academy of Sciences, Beijing 100049, China; (J.G.); (Y.Z.); (X.M.)
| | - Yaru Zhu
- University of Chinese Academy of Sciences, Beijing 100049, China; (J.G.); (Y.Z.); (X.M.)
| | - Xiaoya Ma
- University of Chinese Academy of Sciences, Beijing 100049, China; (J.G.); (Y.Z.); (X.M.)
| | - Guijun Shang
- Shanxi Provincial Key Laboratory of Protein Structure Determination, Shanxi Academy of Advanced Research and Innovation, Taiyuan 030012, China;
| | - Bo Liu
- Key Laboratory of Molecular Virology and Immunology, Chinese Academy of Sciences, Shanghai 200031, China
- Shanghai Huashen Institute of Microbes and Infections, Shanghai 200052, China
| | - Ke Zhang
- Key Laboratory of Molecular Virology and Immunology, Chinese Academy of Sciences, Shanghai 200031, China
| |
Collapse
|
5
|
Yihunie W, Nibret G, Aschale Y. Recent Advances in Messenger Ribonucleic Acid (mRNA) Vaccines and Their Delivery Systems: A Review. Clin Pharmacol 2023; 15:77-98. [PMID: 37554660 PMCID: PMC10405914 DOI: 10.2147/cpaa.s418314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
Messenger ribonucleic acid (mRNA) was found as the intermediary that transfers genetic information from DNA to ribosomes for protein synthesis in 1961. The emergency use authorization of the two covid-19 mRNA vaccines, BNT162b2 and mRNA-1273, is a significant achievement in the history of vaccine development. Because they are generated in a cell-free environment using the in vitro transcription (IVT) process, mRNA vaccines are risk-free. Moreover, chemical modifications to the mRNA molecule, such as cap structures and changed nucleosides, have proved critical in overcoming immunogenicity concerns, achieving sustained stability, and achieving effective, accurate protein production in vivo. Several vaccine delivery strategies (including protamine, lipid nanoparticles (LNPs), polymers, nanoemulsions, and cell-based administration) were also optimized to load and transport RNA into the cytosol. LNPs, which are composed of a cationic or a pH-dependent ionizable lipid layer, a polyethylene glycol (PEG) component, phospholipids, and cholesterol, are the most advanced systems for delivering mRNA vaccines. Moreover, modifications of the four components that make up the LNPs showed to increase vaccine effectiveness and reduce side effects. Furthermore, the introduction of biodegradable lipids improved LNP biocompatibility. Furthermore, mRNA-based therapies are expected to be effective treatments for a variety of refractory conditions, including infectious diseases, metabolic genetic diseases, cancer, cardiovascular and cerebrovascular diseases. Therefore, the present review aims to provide the scientific community with up-to-date information on mRNA vaccines and their delivery systems.
Collapse
Affiliation(s)
- Wubetu Yihunie
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Getinet Nibret
- Department of Pharmacy, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| | - Yibeltal Aschale
- Department of Medical Laboratory Science, College of Health Sciences, Debre Markos University, Debre Markos, Ethiopia
| |
Collapse
|
6
|
Li T, Wang H, Zhang Y, Wang H, Zhang Z, Liu X, Zhang Z, Liu K, Yang D, Zhang H, Gu L. Comprehensive profiling of epigenetic modifications in fast-growing Moso bamboo shoots. PLANT PHYSIOLOGY 2023; 191:1017-1035. [PMID: 36417282 PMCID: PMC9922427 DOI: 10.1093/plphys/kiac525] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/10/2022] [Accepted: 11/17/2022] [Indexed: 05/13/2023]
Abstract
The fast growth of Moso bamboo (Phyllostachys edulis) shoots is caused by the rapid elongation of each internode. However, the key underlying cellular processes and epigenetic mechanisms remain largely unexplored. We used microscopy and multi-omics approaches to investigate two regions (bottom and middle) of the 18th internode from shoots of two different heights (2 and 4 m). We observed that internode cells become longer, and that lignin biosynthesis and glycosyltransferase family 43 (GT43) genes are substantially upregulated with shoot height. Nanopore direct RNA sequencing (DRS) revealed a higher N6-methyladenine (m6A) modification rate in 2-m shoots than in 4-m shoots. In addition, different specific m6A modification sites were enriched at different growth stages. Global DNA methylation profiling indicated that DNA methylation levels are higher in 4-m shoots than in 2-m shoots. We also detected shorter poly(A) tail lengths (PALs) in 4-m shoots compared with 2-m shoots. Genes showing differential PAL were mainly enriched in the functional terms of protein translation and vesicle fusion. An association analysis between PALs and DNA methylation strongly suggested that gene body CG methylation levels are positively associated with PAL. This study provides valuable information to better understand post-transcriptional regulations responsible for fast-growing shoots in Moso bamboo.
Collapse
Affiliation(s)
- Tao Li
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Huihui Wang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yaxin Zhang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Huiyuan Wang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zeyu Zhang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Xuqing Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zekun Zhang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Kai Liu
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Deming Yang
- College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Hangxiao Zhang
- Basic Forestry and Proteomics Research Center, College of Forestry, School of Future Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Lianfeng Gu
- Basic Forestry and Proteomics Research Center, College of Forestry, School of Future Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| |
Collapse
|
7
|
Trkulja KL, Manji F, Kuruvilla J, Laister RC. Nuclear Export in Non-Hodgkin Lymphoma and Implications for Targeted XPO1 Inhibitors. Biomolecules 2023; 13:111. [PMID: 36671496 PMCID: PMC9855521 DOI: 10.3390/biom13010111] [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: 12/01/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 01/06/2023] Open
Abstract
Exportin-1 (XPO1) is a key player in the nuclear export pathway and is overexpressed in almost all cancers. This is especially relevant for non-Hodgkin lymphoma (NHL), where high XPO1 expression is associated with poor prognosis due to its oncogenic role in exporting proteins and RNA that are involved in cancer progression and treatment resistance. Here, we discuss the proteins and RNA transcripts that have been identified as XPO1 cargo in NHL lymphoma including tumour suppressors, immune modulators, and transcription factors, and their implications for oncogenesis. We then highlight the research to date on XPO1 inhibitors such as selinexor and other selective inhibitors of nuclear export (SINEs), which are used to treat some cases of non-Hodgkin lymphoma. In vitro, in vivo, and clinical studies investigating the anti-cancer effects of SINEs from bench to bedside, both as a single agent and in combination, are also reported. Finally, we discuss the limitations of the current research landscape and future directions to better understand and improve the clinical utility of SINE compounds in NHL.
Collapse
Affiliation(s)
- Kyla L. Trkulja
- Institute of Medical Science, University of Toronto, 27 King’s College Circle, Toronto, ON M5S 1A1, Canada
- Division of Medical Oncology and Hematology, Princess Margaret Cancer Centre, University Health Network, 610 University Avenue, Toronto, ON M5G 2C1, Canada
| | - Farheen Manji
- Division of Medical Oncology and Hematology, Princess Margaret Cancer Centre, University Health Network, 610 University Avenue, Toronto, ON M5G 2C1, Canada
| | - John Kuruvilla
- Institute of Medical Science, University of Toronto, 27 King’s College Circle, Toronto, ON M5S 1A1, Canada
- Division of Medical Oncology and Hematology, Princess Margaret Cancer Centre, University Health Network, 610 University Avenue, Toronto, ON M5G 2C1, Canada
| | - Rob C. Laister
- Division of Medical Oncology and Hematology, Princess Margaret Cancer Centre, University Health Network, 610 University Avenue, Toronto, ON M5G 2C1, Canada
| |
Collapse
|
8
|
Chang S, Hedskog C, Parhy B, Martin R, Mo H, Maiorova E, Zoulim F. Sequence characterization of extracellular HBV RNA in patient plasma. J Viral Hepat 2023; 30:29-38. [PMID: 36208116 DOI: 10.1111/jvh.13760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 09/27/2022] [Accepted: 10/02/2022] [Indexed: 12/09/2022]
Abstract
Antiviral nucleos(t)ide analogue therapies inhibit HBV replication and suppress the HBV DNA levels in patients with chronic HBV infection. Since HBV RNAs are expressed from cccDNA or HBV integrated sequences, independently of viral genome replication, levels of HBV RNAs in plasma may remain high following treatment with nucleos(t)ide analogue. Thus, HBV RNAs have been proposed to be used as a viral biomarker for treatment outcome and disease progression. Recent investigations of plasma HBV RNAs described the presence of full length as well as subgenomic forms of RNA. To support the usage of plasma HBV RNAs as a viral biomarker, further understanding of HBV RNA composition in clinical samples is needed. Here, sequence of extracellular HBV RNAs was characterized in plasma samples of patients with chronic HBV infection using two independent RNA amplification methods that do not use HBV-specific primers for amplification: total RNA (NuGEN RNAseq) and mRNA (TruSeq RNAseq). Sequencing coverage was obtained across the full length of HBV genome for both methods, confirming the presence of full-length HBV RNA in plasma. The sequence of HBV RNA was nearly identical to plasma HBV DNA sequence in each sample with only 0-14 (median 4) mismatches over 3 kb. Thus, sequence of HBV RNA plasma reflects the intrahepatic viral reservoir and can be used for monitoring of sequence variants such as resistance in clinical trials. Additionally, RNA splice forms, different polyA tails start positions and presence of HBV-human chimeric transcript were identified.
Collapse
Affiliation(s)
- Silvia Chang
- Gilead Sciences, Inc., Foster City, California, USA
| | | | | | - Ross Martin
- Gilead Sciences, Inc., Foster City, California, USA
| | - Hongmei Mo
- Gilead Sciences, Inc., Foster City, California, USA
| | | | - Fabien Zoulim
- INSERM U1052, CNRS UMR-5286, Cancer Research Center of Lyon (CRCL), Lyon, France
- University of Lyon, Université Claude-Bernard (UCBL), Lyon, France
- Hospices Civils de Lyon (HCL), Lyon, France
| |
Collapse
|
9
|
Cancer cells hijack RNA processing to rewrite the message. Biochem Soc Trans 2022; 50:1447-1456. [PMID: 36282006 PMCID: PMC9704515 DOI: 10.1042/bst20220621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 11/17/2022]
Abstract
Typically, cancer is thought to arise due to DNA mutations, dysregulated transcription and/or aberrant signalling. Recently, it has become clear that dysregulated mRNA processing, mRNA export and translation also contribute to malignancy. RNA processing events result in major modifications to the physical nature of mRNAs such as the addition of the methyl-7-guanosine cap, the removal of introns and the addition of polyA tails. mRNA processing is a critical determinant for the protein-coding capacity of mRNAs since these physical changes impact the efficiency by which a given transcript can be exported to the cytoplasm and translated into protein. While many of these mRNA metabolism steps were considered constitutive housekeeping activities, they are now known to be highly regulated with combinatorial and multiplicative impacts i.e. one event will influence the capacity to undergo others. Furthermore, alternative splicing and/or cleavage and polyadenylation can produce transcripts with alternative messages and new functionalities. The coordinated processing of groups of functionally related RNAs can potently re-wire signalling pathways, modulate survival pathways and even re-structure the cell. As postulated by the RNA regulon model, combinatorial regulation of these groups is achieved by the presence of shared cis-acting elements (known as USER codes) which recruit machinery for processing, export or translation. In all, dysregulated RNA metabolism in cancer gives rise to an altered proteome that in turn elicits biological responses related to malignancy. Studies of these events in cancer revealed new mechanisms underpinning malignancies and unearthed novel therapeutic opportunities. In all, cancer cells coopt RNA processing, export and translation to support their oncogenic activity.
Collapse
|
10
|
Cui YR, Wang SJ, Ma T, Yu P, Chen J, Guo T, Meng G, Jiang B, Dong J, Liu J. KPT330 improves Cas9 precision genome- and base-editing by selectively regulating mRNA nuclear export. Commun Biol 2022; 5:237. [PMID: 35301428 PMCID: PMC8931069 DOI: 10.1038/s42003-022-03188-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 02/22/2022] [Indexed: 12/21/2022] Open
Abstract
CRISPR-based genome engineering tools are associated with off-target effects that constitutively active Cas9 protein may instigate. Previous studies have revealed the feasibility of modulating Cas9-based genome- and base-editing tools using protein or small-molecule CRISPR inhibitors. Here we screened a set of small molecule compounds with irreversible warhead, aiming to identifying small-molecule modulators of CRISPR-Cas9. It was found that selective inhibitors of nuclear export (SINEs) could efficiently inhibit the cellular activity of Cas9 in the form of genome-, base- and prime-editing tools. Interestingly, SINEs did not function as direct inhibitors to Cas9, but modulated Cas9 activities by interfering with the nuclear export process of Cas9 mRNA. Thus, to the best of our knowledge, SINEs represent the first reported indirect, irreversible inhibitors of CRISPR-Cas9. Most importantly, an FDA-approved anticancer drug KPT330, along with other examined SINEs, could improve the specificities of CRISPR-Cas9-based genome- and base editing tools in human cells. Our study expands the toolbox of CRISPR modulating elements and provides a feasible approach to improving the specificity of CRISPR-Cas9-based genome engineering tools. The FDA-approved anti-cancer drug, KPT330, can indirectly inhibit Cas9 by interfering with Cas9 mRNA nuclear export and help reduce off-target editing in cells.
Collapse
Affiliation(s)
- Yan-Ru Cui
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Shao-Jie Wang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Tiancheng Ma
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, 200032, Shanghai, China
| | - Peihong Yu
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China.,University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Jun Chen
- College of Life Sciences, Zhejiang University, 310058, Hangzhou, Zhejiang, China
| | - Taijie Guo
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, 200032, Shanghai, China
| | - Genyi Meng
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, 200032, Shanghai, China
| | - Biao Jiang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Jiajia Dong
- Key Laboratory of Organofluorine Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Road, 200032, Shanghai, China.
| | - Jia Liu
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China. .,Shanghai Clinical Research and Trial Center, 201210, Shanghai, China. .,Gene Editing Center, School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China. .,Guangzhou Laboratory, Guangzhou International Bio Island, No. 9 XingDaoHuanBei Road, 510005, Guangzhou, Guangdong, China.
| |
Collapse
|
11
|
Implications of Poly(A) Tail Processing in Repeat Expansion Diseases. Cells 2022; 11:cells11040677. [PMID: 35203324 PMCID: PMC8870147 DOI: 10.3390/cells11040677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 02/11/2022] [Accepted: 02/13/2022] [Indexed: 11/21/2022] Open
Abstract
Repeat expansion diseases are a group of more than 40 disorders that affect mainly the nervous and/or muscular system and include myotonic dystrophies, Huntington’s disease, and fragile X syndrome. The mutation-driven expanded repeat tract occurs in specific genes and is composed of tri- to dodeca-nucleotide-long units. Mutant mRNA is a pathogenic factor or important contributor to the disease and has great potential as a therapeutic target. Although repeat expansion diseases are quite well known, there are limited studies concerning polyadenylation events for implicated transcripts that could have profound effects on transcript stability, localization, and translation efficiency. In this review, we briefly present polyadenylation and alternative polyadenylation (APA) mechanisms and discuss their role in the pathogenesis of selected diseases. We also discuss several methods for poly(A) tail measurement (both transcript-specific and transcriptome-wide analyses) and APA site identification—the further development and use of which may contribute to a better understanding of the correlation between APA events and repeat expansion diseases. Finally, we point out some future perspectives on the research into repeat expansion diseases, as well as APA studies.
Collapse
|
12
|
Li M, Wang Z, Xie C, Xia X. Advances in mRNA vaccines. MRNA-BASED THERAPEUTICS 2022; 372:295-316. [PMID: 36064266 PMCID: PMC9214710 DOI: 10.1016/bs.ircmb.2022.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
mRNA vaccines have been increasingly recognized as a powerful vaccine platform since the FDA approval of two COVID-19 mRNA vaccines, which demonstrated outstanding prevention efficacy as well as great safety profile. Notably, nucleoside modification and lipid nanoparticle-facilitated delivery has greatly improved the immunogenicity, stability, and translation efficiency of mRNA molecule. Here we review the recent progress in mRNA vaccine development, including nucleoside modification, in vitro synthesis and product purification, and lipid nanoparticle vectors for in vivo delivery and efficient translation. We also briefly introduce the clinical application of mRNA vaccine in preventing infectious diseases and treating inflammatory diseases including cancer.
Collapse
Affiliation(s)
- Mengyun Li
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Zining Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Chunyuan Xie
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Xiaojun Xia
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.
| |
Collapse
|
13
|
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.
Collapse
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
| |
Collapse
|
14
|
LncRNA SFTA1P mediates positive feedback regulation of the Hippo-YAP/TAZ signaling pathway in non-small cell lung cancer. Cell Death Discov 2021; 7:369. [PMID: 34845189 PMCID: PMC8630011 DOI: 10.1038/s41420-021-00761-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/19/2021] [Accepted: 11/05/2021] [Indexed: 12/12/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) regulate numerous biological processes involved in both development and carcinogenesis. Hippo-YAP/TAZ signaling, a critical pathway responsible for organ size control, is often dysregulated in a variety of cancers. However, the nature and function of YAP/TAZ-regulated lncRNAs during tumorigenesis remain largely unexplored. By profiling YAP/TAZ-regulated lncRNAs, we identified SFTA1P as a novel transcriptional target and a positive feedback regulator of YAP/TAZ signaling. Using non-small cell lung cancer (NSCLC) cell lines, we show that SFTA1P is transcriptionally activated by YAP/TAZ in a TEAD-dependent manner. Functionally, knockdown of SFTA1P in NSCLC cell lines inhibited proliferation, induced programmed cell death, and compromised their tumorigenic potential. Mechanistically, SFTA1P knockdown decreased TAZ protein abundance and consequently, the expression of YAP/TAZ transcriptional targets. We provide evidence that this phenomenon could potentially be mediated via its interaction with TAZ mRNA to regulate TAZ translation. Our results reveal SFTA1P as a positive feedback regulator of Hippo-YAP/TAZ signaling, which may serve as the molecular basis for lncRNA-based therapies against YAP/TAZ-driven cancers.
Collapse
|
15
|
De Magistris P. The Great Escape: mRNA Export through the Nuclear Pore Complex. Int J Mol Sci 2021; 22:ijms222111767. [PMID: 34769195 PMCID: PMC8583845 DOI: 10.3390/ijms222111767] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/18/2021] [Accepted: 10/21/2021] [Indexed: 12/30/2022] Open
Abstract
Nuclear export of messenger RNA (mRNA) through the nuclear pore complex (NPC) is an indispensable step to ensure protein translation in the cytoplasm of eukaryotic cells. mRNA is not translocated on its own, but it forms ribonuclear particles (mRNPs) in association with proteins that are crucial for its metabolism, some of which; like Mex67/MTR2-NXF1/NXT1; are key players for its translocation to the cytoplasm. In this review, I will summarize our current body of knowledge on the basic characteristics of mRNA export through the NPC. To be granted passage, the mRNP cargo needs to bind transport receptors, which facilitate the nuclear export. During NPC transport, mRNPs undergo compositional and conformational changes. The interactions between mRNP and the central channel of NPC are described; together with the multiple quality control steps that mRNPs undergo at the different rings of the NPC to ensure only proper export of mature transcripts to the cytoplasm. I conclude by mentioning new opportunities that arise from bottom up approaches for a mechanistic understanding of nuclear export.
Collapse
|
16
|
Tao M, Zheng M, Xu Y, Ma S, Zhang W, Ju S. CircRNAs and their regulatory roles in cancers. Mol Med 2021; 27:94. [PMID: 34445958 PMCID: PMC8393742 DOI: 10.1186/s10020-021-00359-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 08/18/2021] [Indexed: 01/17/2023] Open
Abstract
Circular RNAs (circRNAs), a novel type of non-coding RNAs (ncRNAs), have a covalently closed circular structure resulting from pre-mRNA back splicing via spliceosome and ribozymes. They can be classified differently in accordance with different criteria. As circRNAs are abundant, conserved, and stable, they can be used as diagnostic markers in various diseases and targets to develop new therapies. There are various functions of circRNAs, including sponge for miR/proteins, role of scaffolds, templates for translation, and regulators of mRNA translation and stability. Without m7G cap and poly-A tail, circRNAs can still be degraded in several ways, including RNase L, Ago-dependent, and Ago-independent degradation. Increasing evidence indicates that circRNAs can be modified by N-6 methylation (m6A) in many aspects such as biogenesis, nuclear export, translation, and degradation. In addition, they have been proved to play a regulatory role in the progression of various cancers. Recently, methods of detecting circRNAs with high sensitivity and specificity have also been reported. This review presents a detailed overview of circRNAs regarding biogenesis, biomarker, functions, degradation, and dynamic modification as well as their regulatory roles in various cancers. It’s particularly summarized in detail in the biogenesis of circRNAs, regulation of circRNAs by m6A modification and mechanisms by which circRNAs affect tumor progression respectively. Moreover, existing circRNA detection methods and their characteristics are also mentioned.
Collapse
Affiliation(s)
- Mei Tao
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China.,Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.,Medical School of Nantong University, Nantong University, Nantong, 226001, Jiangsu, China
| | - Ming Zheng
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China.,Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.,Medical School of Nantong University, Nantong University, Nantong, 226001, Jiangsu, China
| | - Yanhua Xu
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China.,Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.,Medical School of Nantong University, Nantong University, Nantong, 226001, Jiangsu, China
| | - Shuo Ma
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China.,Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.,Medical School of Nantong University, Nantong University, Nantong, 226001, Jiangsu, China
| | - Weiwei Zhang
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China. .,Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, 226001, Jiangsu, China.
| | - Shaoqing Ju
- Department of Laboratory Medicine, Affiliated Hospital of Nantong University, Xisi Road, No.20, Nantong, 226001, Jiangsu, China.
| |
Collapse
|
17
|
Tatomer DC, Liang D, Wilusz JE. RNAi Screening to Identify Factors That Control Circular RNA Localization. Methods Mol Biol 2021; 2209:321-332. [PMID: 33201478 DOI: 10.1007/978-1-0716-0935-4_20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Thousands of eukaryotic protein-coding genes are noncanonically spliced to generate circular RNAs that have covalently linked ends. These transcripts are resistant to degradation by exonucleases, which enables some to accumulate to higher levels than the associated linear mRNA. In general, exonic circular RNAs accumulate in the cytoplasm, but functions for most of these transcripts remain unknown. It has been proposed that some may modulate the activity of microRNAs or RNA-binding proteins, be translated to yield protein products, or regulate innate immune responses. Recent work has revealed that circular RNAs are exported from the nucleus in a length-dependent manner and that the subcellular localization of these transcripts can be controlled by the DExH/D-box helicase Hel25E in Drosophila. Here, we describe how RNAi screening combined with subcellular fractionation and quantitative reverse transcription PCR (RT-qPCR) can be used to identify regulators of circular RNA localization in Drosophila cells. Long double-stranded RNAs (dsRNAs) that activate the RNA interference (RNAi) pathway are used to deplete factors of interest followed by biochemical fractionation to separate nuclear and cytoplasmic RNAs. RT-qPCR primers that amplify across the backsplicing junction of specific circular RNAs are then used to quantify the relative amounts of these transcripts in the nuclear and cytoplasmic compartments. In total, this approach can be broadly used to characterize circular RNA nuclear export and localization mechanisms, including to identify novel regulatory factors and their breadth of circular RNA targets.
Collapse
Affiliation(s)
- Deirdre C Tatomer
- Department of Biochemistry & Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Dongming Liang
- Department of Biochemistry & Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Jeremy E Wilusz
- Department of Biochemistry & Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
| |
Collapse
|
18
|
The Nuclear Pore Complex and mRNA Export in Cancer. Cancers (Basel) 2020; 13:cancers13010042. [PMID: 33375634 PMCID: PMC7796397 DOI: 10.3390/cancers13010042] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/11/2020] [Accepted: 12/22/2020] [Indexed: 02/07/2023] Open
Abstract
Export of mRNAs from the nucleus to the cytoplasm is a key regulatory step in the expression of proteins. mRNAs are transported through the nuclear pore complex (NPC). Export of mRNAs responds to a variety of cellular stimuli and stresses. Revelations of the specific effects elicited by NPC components and associated co-factors provides a molecular basis for the export of selected RNAs, independent of bulk mRNA export. Aberrant RNA export has been observed in primary human cancer specimens. These cargo RNAs encode factors involved in nearly all facets of malignancy. Indeed, the NPC components involved in RNA export as well as the RNA export machinery can be found to be dysregulated, mutated, or impacted by chromosomal translocations in cancer. The basic mechanisms associated with RNA export with relation to export machinery and relevant NPC components are described. Therapeutic strategies targeting this machinery in clinical trials is also discussed. These findings firmly position RNA export as a targetable feature of cancer along with transcription and translation.
Collapse
|
19
|
Guha S, Bhaumik SR. Viral regulation of mRNA export with potentials for targeted therapy. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1864:194655. [PMID: 33246183 DOI: 10.1016/j.bbagrm.2020.194655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/15/2020] [Accepted: 11/05/2020] [Indexed: 12/12/2022]
Abstract
Eukaryotic gene expression begins with transcription in the nucleus to synthesize mRNA (messenger RNA), which is subsequently exported to the cytoplasm for translation to protein. Like transcription and translation, mRNA export is an important regulatory step of eukaryotic gene expression. Various factors are involved in regulating mRNA export, and thus gene expression. Intriguingly, some of these factors interact with viral proteins, and such interactions interfere with mRNA export of the host cell, favoring viral RNA export. Hence, viruses hijack host mRNA export machinery for export of their own RNAs from nucleus to cytoplasm for translation to proteins for viral life cycle, suppressing host mRNA export (and thus host gene expression and immune/antiviral response). Therefore, the molecules that can impair the interactions of these mRNA export factors with viral proteins could emerge as antiviral therapeutic agents to suppress viral RNA transport and enhance host mRNA export, thereby promoting host gene expression and immune response. Thus, there has been a number of studies to understand how virus hijacks mRNA export machinery in suppressing host gene expression and promoting its own RNA export to the cytoplasm for translation to proteins required for viral replication/assembly/life cycle towards developing targeted antiviral therapies, as concisely described here.
Collapse
Affiliation(s)
- Shalini Guha
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
| | - Sukesh R Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA.
| |
Collapse
|
20
|
Role of Viral Ribonucleoproteins in Human Papillomavirus Type 16 Gene Expression. Viruses 2020; 12:v12101110. [PMID: 33007936 PMCID: PMC7600041 DOI: 10.3390/v12101110] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 09/25/2020] [Accepted: 09/26/2020] [Indexed: 02/06/2023] Open
Abstract
Human papillomaviruses (HPVs) depend on the cellular RNA-processing machineries including alternative RNA splicing and polyadenylation to coordinate HPV gene expression. HPV RNA processing is controlled by cis-regulatory RNA elements and trans-regulatory factors since the HPV splice sites are suboptimal. The definition of HPV exons and introns may differ between individual HPV mRNA species and is complicated by the fact that many HPV protein-coding sequences overlap. The formation of HPV ribonucleoproteins consisting of HPV pre-mRNAs and multiple cellular RNA-binding proteins may result in the different outcomes of HPV gene expression, which contributes to the HPV life cycle progression and HPV-associated cancer development. In this review, we summarize the regulation of HPV16 gene expression at the level of RNA processing with focus on the interactions between HPV16 pre-mRNAs and cellular RNA-binding factors.
Collapse
|
21
|
Sharma M, Wente SR. Nucleocytoplasmic shuttling of Gle1 impacts DDX1 at transcription termination sites. Mol Biol Cell 2020; 31:2398-2408. [PMID: 32755435 PMCID: PMC7851961 DOI: 10.1091/mbc.e20-03-0215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Gle1 is a nucleocytoplasmic shuttling protein with well-documented cytoplasmic roles as a modulator of ATP-dependent DEAD-box RNA helicases involved in messenger (m)RNA export, translation initiation and termination, and stress granule dynamics. Here, we identify a novel nuclear role for Gle1 during transcription termination. In HeLa cells treated with a peptide that disrupts Gle1 nucleocytoplasmic shuttling, we detected nuclear accumulation of specific mRNAs with elongated 3′-UTR (untranslated region). Enriched mRNAs were nascently transcribed and accumulated in the nucleus due to a change in transcription state and not due to altered nuclear export. Whereas Gle1 shuttling inhibition did not appear to perturb nuclear DDX19 functions, it did result in increased DDX1 nucleoplasmic localization and decreased DDX1 interactions with Gle1 and the pre-mRNA cleavage stimulation factor CstF-64. An increase in nuclear R-loop signal intensity was also observed with diminished Gle1 shuttling, as well as colocalization of Gle1 at R-loops. Taken together, these studies reveal a nuclear role for Gle1 in coordinating DDX1 function in transcription termination complexes.
Collapse
Affiliation(s)
- Manisha Sharma
- Department of Cell and Developmental Biology, School of Medicine, Vanderbilt University, Nashville, TN 37240
| | - Susan R Wente
- Department of Cell and Developmental Biology, School of Medicine, Vanderbilt University, Nashville, TN 37240
| |
Collapse
|
22
|
Nourse J, Spada S, Danckwardt S. Emerging Roles of RNA 3'-end Cleavage and Polyadenylation in Pathogenesis, Diagnosis and Therapy of Human Disorders. Biomolecules 2020; 10:biom10060915. [PMID: 32560344 PMCID: PMC7356254 DOI: 10.3390/biom10060915] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/10/2020] [Accepted: 06/13/2020] [Indexed: 12/11/2022] Open
Abstract
A crucial feature of gene expression involves RNA processing to produce 3′ ends through a process termed 3′ end cleavage and polyadenylation (CPA). This ensures the nascent RNA molecule can exit the nucleus and be translated to ultimately give rise to a protein which can execute a function. Further, alternative polyadenylation (APA) can produce distinct transcript isoforms, profoundly expanding the complexity of the transcriptome. CPA is carried out by multi-component protein complexes interacting with multiple RNA motifs and is tightly coupled to transcription, other steps of RNA processing, and even epigenetic modifications. CPA and APA contribute to the maintenance of a multitude of diverse physiological processes. It is therefore not surprising that disruptions of CPA and APA can lead to devastating disorders. Here, we review potential CPA and APA mechanisms involving both loss and gain of function that can have tremendous impacts on health and disease. Ultimately we highlight the emerging diagnostic and therapeutic potential CPA and APA offer.
Collapse
Affiliation(s)
- Jamie Nourse
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
| | - Stefano Spada
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
| | - Sven Danckwardt
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Rhine-Main, Germany
- Correspondence:
| |
Collapse
|
23
|
Gomar-Alba M, Mendoza M. Modulation of Cell Identity by Modification of Nuclear Pore Complexes. Front Genet 2020; 10:1301. [PMID: 31969901 PMCID: PMC6960265 DOI: 10.3389/fgene.2019.01301] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/26/2019] [Indexed: 11/17/2022] Open
Abstract
Nuclear pore complexes (NPCs) are protein assemblies that form channels across the nuclear envelope to mediate communication between the nucleus and the cytoplasm. Additionally, NPCs interact with chromatin and influence the position and expression of multiple genes. Interestingly, the composition of NPCs can vary in different cell-types, tissues, and developmental states. Here, we review recent findings suggesting that modifications of NPC composition, including post-translational modifications, play an instructive role in cell fate establishment. In particular, we focus on the role of cell-specific NPC deacetylation in asymmetrically dividing budding yeast, which modulates transport-dependent and transport-independent NPC functions to determine the time of commitment to a new division cycle in daughter cells. By modulating protein localization and gene expression, NPCs are therefore emerging as central regulators of cell identity.
Collapse
Affiliation(s)
- Mercè Gomar-Alba
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Centre National de la Recherche Scientifique, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, Illkirch, France.,Université de Strasbourg, Strasbourg, France
| | - Manuel Mendoza
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France.,Centre National de la Recherche Scientifique, Illkirch, France.,Institut National de la Santé et de la Recherche Médicale, Illkirch, France.,Université de Strasbourg, Strasbourg, France
| |
Collapse
|
24
|
Genome-wide profiling reveals alternative polyadenylation of mRNA in human non-small cell lung cancer. J Transl Med 2019; 17:257. [PMID: 31391087 PMCID: PMC6686416 DOI: 10.1186/s12967-019-1986-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/17/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Lung cancer is the second most common cancer with an extremely poor overall survival rate. Post-transcriptional regulation of gene expression play many important roles in human cancer, and one of the potential mechanisms underlying this is alternative mRNA maturation at its 3' untranslated regions (3'-UTRs). METHODS Cancer tissues and paired adjacent normal lung tissues from 26 patients diagnosed with non-small cell lung cancer (NSCLC) were analyzed by in vitro transcription-sequencing alternative polyadenylation sites (IVT-SAPAS). 41,773,101 reads in average were obtained from each paired sample. A potential regulation of Cleavage Stimulation Factor Subunit 2 (CSTF2) on 3'UTR length of genes was tested in H460 cells. RESULTS 1439 (10.26%) genes showed up-regulated expression and 1364 (9.72%) genes showed down-regulated expression in lung cancer tissue versus normal lung tissue, and shorten 3'UTR in cancer tissue was detected in cancer tissues collected from 96.2% (25/26) patients, indicating lung cancer tend to have shortened 3'UTRs of these identified genes. KEGG analysis showed 1855 genes with shorten 3'UTR were enriched in mTOR signaling, ubiquitin mediated proteolysis and RNA degradation. Knocking down CSTF2 expression in H460 cells results in 3'UTR elongation of genes that was identified to be with shortened length in cancer tissues. CONCLUSION Alternative polyadenylation (APA) site-switching of 3'UTRs is prevalent in NSCLC, and CSTF2 may serve as an oncogene regulates the 3'UTR length of cancer related genes in NSCLC.
Collapse
|
25
|
Herdy B, Mayer C, Varshney D, Marsico G, Murat P, Taylor C, D'Santos C, Tannahill D, Balasubramanian S. Analysis of NRAS RNA G-quadruplex binding proteins reveals DDX3X as a novel interactor of cellular G-quadruplex containing transcripts. Nucleic Acids Res 2019; 46:11592-11604. [PMID: 30256975 PMCID: PMC6265444 DOI: 10.1093/nar/gky861] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/12/2018] [Indexed: 12/23/2022] Open
Abstract
RNA G-quadruplexes (rG4s) are secondary structures in mRNAs known to influence RNA post-transcriptional mechanisms thereby impacting neurodegenerative disease and cancer. A detailed knowledge of rG4–protein interactions is vital to understand rG4 function. Herein, we describe a systematic affinity proteomics approach that identified 80 high-confidence interactors that assemble on the rG4 located in the 5′-untranslated region (UTR) of the NRAS oncogene. Novel rG4 interactors included DDX3X, DDX5, DDX17, GRSF1 and NSUN5. The majority of identified proteins contained a glycine-arginine (GAR) domain and notably GAR-domain mutation in DDX3X and DDX17 abrogated rG4 binding. Identification of DDX3X targets by transcriptome-wide individual-nucleotide resolution UV-crosslinking and affinity enrichment (iCLAE) revealed a striking association with 5′-UTR rG4-containing transcripts which was reduced upon GAR-domain mutation. Our work highlights hitherto unrecognized features of rG4 structure–protein interactions that highlight new roles of rG4 structures in mRNA post-transcriptional control.
Collapse
Affiliation(s)
- Barbara Herdy
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Clemens Mayer
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, Netherlands.,Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW, UK
| | - Dhaval Varshney
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Giovanni Marsico
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Pierre Murat
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.,Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW, UK
| | - Chris Taylor
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.,Bioscience Technology Facility, Department of Biology, University of York, York YO10 5DD, UK
| | - Clive D'Santos
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - David Tannahill
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK
| | - Shankar Balasubramanian
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, UK.,Department of Chemistry, University of Cambridge Lensfield Road, Cambridge CB2 1EW, UK
| |
Collapse
|
26
|
Abstract
Nuclear pore complexes (NPCs) mediate nucleocytoplasmic exchange. They are exceptionally large protein complexes that fuse the inner and outer nuclear membranes to form channels across the nuclear envelope. About 30 different protein components, termed nucleoporins, assemble in multiple copies into an intricate cylindrical architecture. Here, we review our current knowledge of the structure of nucleoporins and how those come together in situ. We delineate architectural principles on several hierarchical organization levels, including isoforms, posttranslational modifications, nucleoporins, and higher-order oligomerization of nucleoporin subcomplexes. We discuss how cells exploit this modularity to faithfully assemble NPCs.
Collapse
Affiliation(s)
- Bernhard Hampoelz
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany; , ,
| | - Amparo Andres-Pons
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany; , , .,Current affiliation: Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland;
| | - Panagiotis Kastritis
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany; , , .,Current affiliation: ZIK HALOmem, Martin Luther University of Halle-Wittenberg, 06120 Halle (Saale), Germany
| | - Martin Beck
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany; , , .,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, 69117 Heidelberg, Germany.,Max Planck Institute of Biophysics, 60438 Frankfurt am Main, Germany
| |
Collapse
|
27
|
Abstract
In eukaryotes, the separation of translation from transcription by the nuclear envelope enables mRNA modifications such as capping, splicing, and polyadenylation. These modifications are mediated by a spectrum of ribonuclear proteins that associate with preRNA transcripts, coordinating the different steps and coupling them to nuclear export, ensuring that only mature transcripts reach the cytoplasmic translation machinery. Although the components of this machinery have been identified and considerable functional insight has been achieved, a number of questions remain outstanding about mRNA nuclear export and how it is integrated into the nuclear phase of the gene expression pathway. Nuclear export factors mediate mRNA transit through nuclear pores to the cytoplasm, after which these factors are removed from the mRNA, preventing transcripts from returning to the nucleus. However, as outlined in this review, several aspects of the mechanism by which transport factor binding and release are mediated remain unclear, as are the roles of accessory nuclear components in these processes. Moreover, the mechanisms by which completion of mRNA splicing and polyadenylation are recognized, together with how they are coordinated with nuclear export, also remain only partially characterized. One attractive hypothesis is that dissociating poly(A) polymerase from the cleavage and polyadenylation machinery could signal completion of mRNA maturation and thereby provide a mechanism for initiating nuclear export. The impressive array of genetic, molecular, cellular, and structural data that has been generated about these systems now provides many of the tools needed to define the precise mechanisms involved in these processes and how they are integrated.
Collapse
Affiliation(s)
- Murray Stewart
- From the MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, United Kingdom
| |
Collapse
|
28
|
Battaglia-Hsu SF, Ghemrawi R, Coelho D, Dreumont N, Mosca P, Hergalant S, Gauchotte G, Sequeira JM, Ndiongue M, Houlgatte R, Alberto JM, Umoret R, Robert A, Paoli J, Jung M, Quadros EV, Guéant JL. Inherited disorders of cobalamin metabolism disrupt nucleocytoplasmic transport of mRNA through impaired methylation/phosphorylation of ELAVL1/HuR. Nucleic Acids Res 2018; 46:7844-7857. [PMID: 30016500 PMCID: PMC6125644 DOI: 10.1093/nar/gky634] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 06/26/2018] [Accepted: 07/12/2018] [Indexed: 12/12/2022] Open
Abstract
The molecular mechanisms that underlie the neurological manifestations of patients with inherited diseases of vitamin B12 (cobalamin) metabolism remain to date obscure. We observed transcriptomic changes of genes involved in RNA metabolism and endoplasmic reticulum stress in a neuronal cell model with impaired cobalamin metabolism. These changes were related to the subcellular mislocalization of several RNA binding proteins, including the ELAVL1/HuR protein implicated in neuronal stress, in this cell model and in patient fibroblasts with inborn errors of cobalamin metabolism and Cd320 knockout mice. The decreased interaction of ELAVL1/HuR with the CRM1/exportin protein of the nuclear pore complex and its subsequent mislocalization resulted from hypomethylation at R-217 produced by decreased S-adenosylmethionine and protein methyl transferase CARM1 and dephosphorylation at S221 by increased protein phosphatase PP2A. The mislocalization of ELAVL1/HuR triggered the decreased expression of SIRT1 deacetylase and genes involved in brain development, neuroplasticity, myelin formation, and brain aging. The mislocalization was reversible upon treatment with siPpp2ca, cobalamin, S-adenosylmethionine, or PP2A inhibitor okadaic acid. In conclusion, our data highlight the key role of the disruption of ELAVL1/HuR nuclear export, with genomic changes consistent with the effects of inborn errors of Cbl metabolisms on brain development, neuroplasticity and myelin formation.
Collapse
Affiliation(s)
- Shyue-Fang Battaglia-Hsu
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Rose Ghemrawi
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - David Coelho
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Natacha Dreumont
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Pauline Mosca
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Sébastien Hergalant
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Guillaume Gauchotte
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Jeffrey M Sequeira
- Division of Hematology/Oncology, Department of Medicine, SUNY-Downstate Medical Center, Brooklyn, New York, NY, USA
| | - Mariam Ndiongue
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Rémi Houlgatte
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Jean-Marc Alberto
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Remy Umoret
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Aurélie Robert
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Justine Paoli
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| | - Martin Jung
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Building 44, Homburg 66421, Germany
| | - Edward V Quadros
- Division of Hematology/Oncology, Department of Medicine, SUNY-Downstate Medical Center, Brooklyn, New York, NY, USA
| | - Jean-Louis Guéant
- INSERM UMRS 954 NGERE – Nutrition, Genetics, and Environmental Risk Exposure and National Center of Inborn Errors of Metabolism, Faculty of Medicine of Nancy, University of Lorraine and University Regional Hospital Center of Nancy, Vandoeuvre-lès-Nancy, F-54000, France
| |
Collapse
|
29
|
Corbett AH. Post-transcriptional regulation of gene expression and human disease. Curr Opin Cell Biol 2018; 52:96-104. [PMID: 29518673 PMCID: PMC5988930 DOI: 10.1016/j.ceb.2018.02.011] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/08/2018] [Accepted: 02/15/2018] [Indexed: 12/18/2022]
Abstract
A large number of mutations in genes that encode RNA binding proteins cause human disease. Many of these RNA binding proteins mediate key steps in post-transcriptional regulation of gene expression from mRNA processing to eventual decay in the cytoplasm. Surprisingly, these RNA binding proteins, which are ubiquitously expressed and play fundamental roles in gene expression, are often altered in tissue-specific disease. Mutations linked to disease impact nearly every post-transcriptional processing step and cause diverse disease phenotypes in a variety of specific tissues. This review summarizes steps in post-transcriptional regulation of gene expression that have been linked to disease providing specific examples of some of the many genes affected. Finally, recent advances that hold promise for treatment of some of these diseases are presented.
Collapse
Affiliation(s)
- Anita H Corbett
- Department of Biology, RRC 1021, Emory University, 1510 Clifton Road, NE, Atlanta 30322, GA, United States.
| |
Collapse
|
30
|
Huang C, Liang D, Tatomer DC, Wilusz JE. A length-dependent evolutionarily conserved pathway controls nuclear export of circular RNAs. Genes Dev 2018; 32:639-644. [PMID: 29773557 PMCID: PMC6004072 DOI: 10.1101/gad.314856.118] [Citation(s) in RCA: 226] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 04/24/2018] [Indexed: 11/26/2022]
Abstract
Here, Huang et al. investigated how circRNA localization or nuclear export is controlled and, using RNAi screening, found that depletion of the Drosophila DExH/D-box helicase Hel25E results in nuclear accumulation of long (>800-nt), but not short, circRNAs. Their findings suggest that the lengths of mature circRNAs are measured to dictate the mode of nuclear export. Circular RNAs (circRNAs) are generated from many protein-coding genes. Most accumulate in the cytoplasm, but how circRNA localization or nuclear export is controlled remains unclear. Using RNAi screening, we found that depletion of the Drosophila DExH/D-box helicase Hel25E results in nuclear accumulation of long (>800-nucleotide), but not short, circRNAs. The human homologs of Hel25E similarly regulate circRNA localization, as depletion of UAP56 (DDX39B) or URH49 (DDX39A) causes long and short circRNAs, respectively, to become enriched in the nucleus. These data suggest that the lengths of mature circRNAs are measured to dictate the mode of nuclear export.
Collapse
Affiliation(s)
- Chuan Huang
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Dongming Liang
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Deirdre C Tatomer
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Jeremy E Wilusz
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| |
Collapse
|
31
|
Abstract
It is commonly observed that proteasome impairment results in accumulation of ubiquitinated proteins in the cytosol. Even proteins originally located in the nucleus show similar cytosolic accumulation, suggesting that unidentified machinery proactively transports them to the cytosol. Here, we report that a protein complex, UBIN–polyubiquitinated substrate transporter, harboring ubiquitin binding domain and nuclear export signal specifically mediates this process. In addition, their worm homologues showing similar transportation activity are important to maintain the lifespan of worms under natural condition. Our findings provide an answer to the long-standing question of why ubiquitinated proteins are deposited in the cytosol by proteasome impairment; they provide definite identification of underlying molecular machinery and show its essential involvement in the proteostasis in animal cells. Although mechanisms for protein homeostasis in the cytosol have been studied extensively, those in the nucleus remain largely unknown. Here, we identified that a protein complex mediates export of polyubiquitinated proteins from the nucleus to the cytosol. UBIN, a ubiquitin-associated (UBA) domain-containing protein, shuttled between the nucleus and the cytosol in a CRM1-dependent manner, despite the lack of intrinsic nuclear export signal (NES). Instead, the UBIN binding protein polyubiquitinated substrate transporter (POST) harboring an NES shuttled UBIN through nuclear pores. UBIN bound to polyubiquitin chain through its UBA domain, and the UBIN-POST complex exported them from the nucleus to the cytosol. Ubiquitinated proteins accumulated in the cytosol in response to proteasome inhibition, whereas cotreatment with CRM1 inhibitor led to their accumulation in the nucleus. Our results suggest that ubiquitinated proteins are exported from the nucleus to the cytosol in the UBIN-POST complex-dependent manner for the maintenance of nuclear protein homeostasis.
Collapse
|
32
|
Chatterjee K, Majumder S, Wan Y, Shah V, Wu J, Huang HY, Hopper AK. Sharing the load: Mex67-Mtr2 cofunctions with Los1 in primary tRNA nuclear export. Genes Dev 2017; 31:2186-2198. [PMID: 29212662 PMCID: PMC5749166 DOI: 10.1101/gad.305904.117] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 11/06/2017] [Indexed: 11/24/2022]
Abstract
Here, Chatterjee et al. describe a novel tRNA nuclear export pathway that functions in parallel to the tRNA nuclear exporter Los1. They provide molecular, genetic, cytological, and biochemical evidence that the Mex67–Mtr2 (TAP–p15) heterodimer, best characterized for its essential role in mRNA nuclear export, cofunctions with Los1 in tRNA nuclear export. Eukaryotic transfer RNAs (tRNAs) are exported from the nucleus, their site of synthesis, to the cytoplasm, their site of function for protein synthesis. The evolutionarily conserved β-importin family member Los1 (Exportin-t) has been the only exporter known to execute nuclear export of newly transcribed intron-containing pre-tRNAs. Interestingly, LOS1 is unessential in all tested organisms. As tRNA nuclear export is essential, we previously interrogated the budding yeast proteome to identify candidates that function in tRNA nuclear export. Here, we provide molecular, genetic, cytological, and biochemical evidence that the Mex67–Mtr2 (TAP–p15) heterodimer, best characterized for its essential role in mRNA nuclear export, cofunctions with Los1 in tRNA nuclear export. Inactivation of Mex67 or Mtr2 leads to rapid accumulation of end-matured unspliced tRNAs in the nucleus. Remarkably, merely fivefold overexpression of Mex67–Mtr2 can substitute for Los1 in los1Δ cells. Moreover, in vivo coimmunoprecipitation assays with tagged Mex67 document that the Mex67 binds tRNAs. Our data also show that tRNA exporters surprisingly exhibit differential tRNA substrate preferences. The existence of multiple tRNA exporters, each with different tRNA preferences, may indicate that the proteome can be regulated by tRNA nuclear export. Thus, our data show that Mex67–Mtr2 functions in primary nuclear export for a subset of yeast tRNAs.
Collapse
Affiliation(s)
- Kunal Chatterjee
- The Ohio State University Comprehensive Cancer Research Center, The Ohio State University, Columbus, Ohio 43210, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Shubhra Majumder
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Yao Wan
- The Ohio State University Comprehensive Cancer Research Center, The Ohio State University, Columbus, Ohio 43210, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Vijay Shah
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA
| | - Jingyan Wu
- The Ohio State University Comprehensive Cancer Research Center, The Ohio State University, Columbus, Ohio 43210, USA.,Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Hsiao-Yun Huang
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Anita K Hopper
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, USA.,Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA
| |
Collapse
|
33
|
Beck M, Schirmacher P, Singer S. Alterations of the nuclear transport system in hepatocellular carcinoma - New basis for therapeutic strategies. J Hepatol 2017; 67:1051-1061. [PMID: 28673770 DOI: 10.1016/j.jhep.2017.06.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/20/2017] [Accepted: 06/21/2017] [Indexed: 12/20/2022]
Abstract
Hepatocellular carcinoma (HCC) is among the most prevalent human malignancies worldwide with rising incidence in industrialised countries, few therapeutic options and poor prognosis. To expand and improve therapeutic strategies, identification of drug targets involved in several liver cancer-related pathways is crucial. Virtually all signal transduction cascades cross the nuclear envelope and therefore require components of the nuclear transport system (NTS), including nuclear transport receptors (e.g. importins and exportins) and the nuclear pore complex. Accordingly, members of the NTS represent promising targets for therapeutic intervention. Selective inhibitors of nuclear export have already entered clinical trials for various malignancies. Herein, we review the current knowledge regarding alterations of the NTS and their potential for targeted therapy in HCC.
Collapse
Affiliation(s)
- Martin Beck
- European Molecular Biology Laboratory, Heidelberg, Germany
| | | | - Stephan Singer
- European Molecular Biology Laboratory, Heidelberg, Germany; Institute of Pathology, University Hospital Heidelberg, Germany.
| |
Collapse
|
34
|
Fu B, Zhao M, Wang L, Patil G, Smith JA, Juncadella IJ, Zuvela-Jelaska L, Dorf ME, Li S. RNAi Screen and Proteomics Reveal NXF1 as a Novel Regulator of IRF5 Signaling. Sci Rep 2017; 7:2683. [PMID: 28578407 PMCID: PMC5457443 DOI: 10.1038/s41598-017-02857-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 04/20/2017] [Indexed: 01/25/2023] Open
Abstract
Interferon regulatory factor 5 (IRF5) is a key transcription factor of innate immunity, which plays an important role in host restriction to viral infection and inflammation. Genome-wide association studies have implied the association of IRF5 with several autoimmune diseases, including systemic lupus erythematosus (SLE), Sjogren's syndrome, inflammatory bowel disease and multiple sclerosis. However, the regulation of IRF5-mediated immunity is not well understood. To uncover new regulators in IRF5 pathway, we used two "omics" approaches: affinity purification coupled with mass spectrometry and a high throughput RNAi screen. Proteomics identified 16 new IRF5 interactors while RNAi-mediated knockdown found 43 regulators of the TLR7-dependent IRF5 signaling pathway. NXF1 was identified in both screens. Stimulation with TLR7 ligand enhances formation of IRF5-NXF1 protein complexes. Gain or loss-of-function experiments revealed NXF1 selectively regulates TLR7-driven IRF5 transcriptional activity, suggesting a new role for NXF1 in the IRF5 signaling pathway.
Collapse
Affiliation(s)
- Bishi Fu
- Department of Microbiology & Immunobiology, Harvard Medical School, Boston, Massachusetts, 02115, USA.,College of Life Science, Yangtze University, Jingzhou, Hubei, 434025, People's Republic of China
| | - Mengmeng Zhao
- Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma, 74078, USA
| | - Lingyan Wang
- Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma, 74078, USA
| | - Girish Patil
- Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma, 74078, USA
| | - Jennifer A Smith
- Department of Microbiology & Immunobiology, Harvard Medical School, Boston, Massachusetts, 02115, USA.,ICCB-Longwood Screening Facility, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Ignacio J Juncadella
- Department of Immunology and Respiratory Diseases Research, Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, Connecticut, 06877, USA
| | - Ljiljana Zuvela-Jelaska
- Department of Immunology and Respiratory Diseases Research, Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, Connecticut, 06877, USA
| | - Martin E Dorf
- Department of Microbiology & Immunobiology, Harvard Medical School, Boston, Massachusetts, 02115, USA.
| | - Shitao Li
- Department of Physiological Sciences, Oklahoma State University, Stillwater, Oklahoma, 74078, USA.
| |
Collapse
|
35
|
Martins RP, Fåhraeus R. A matter of maturity: The impact of pre-mRNA processing in gene expression and antigen presentation. Int J Biochem Cell Biol 2017; 91:203-211. [PMID: 28549625 DOI: 10.1016/j.biocel.2017.05.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 05/15/2017] [Accepted: 05/18/2017] [Indexed: 12/28/2022]
Abstract
RNA processing plays a pivotal role in the diversification of high eukaryotes transcriptome and proteome. The expression of gene products controlling a variety of cellular and physiological processes depends largely on a complex maturation process undergone by pre-mRNAs to become translation-competent mRNAs. Here we review the different mechanisms involved in the pre-mRNA processing and disclose their impact in the gene regulation process in eukaryotic cells. We describe some viral strategies targeting pre-mRNA processing to control gene expression and host immune response and discuss their relevance as tools for a better understanding of cell biology. Finally, we highlight accumulating evidences toward the occurrence of a translation event coupled to mRNA biogenesis in the nuclear compartment and argue how this is relevant for the production of antigenic peptide substrates for the major histocompatibility complex class I pathway.
Collapse
Affiliation(s)
- Rodrigo Prado Martins
- Équipe Labellisée Ligue Contre le Cancer, Université Paris 7, INSERM UMR 1162, 27 rue Juliette Dodu, 75010 Paris, France.
| | - Robin Fåhraeus
- Équipe Labellisée Ligue Contre le Cancer, Université Paris 7, INSERM UMR 1162, 27 rue Juliette Dodu, 75010 Paris, France; Department of Medical Biosciences, Umeå University, Umeå, Sweden; RECAMO, Masaryk Memorial Cancer Institute, Brno, Czech Republic
| |
Collapse
|
36
|
Gudde AEEG, van Kessel IDG, André LM, Wieringa B, Wansink DG. Trinucleotide-repeat expanded and normal DMPK transcripts contain unusually long poly(A) tails despite differential nuclear residence. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:740-749. [PMID: 28435090 DOI: 10.1016/j.bbagrm.2017.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 03/26/2017] [Accepted: 04/14/2017] [Indexed: 12/29/2022]
Abstract
In yeast and higher eukaryotes nuclear retention of transcripts may serve in control over RNA decay, nucleocytoplasmic transport and premature cytoplasmic appearance of mRNAs. Hyperadenylation of RNA is known to be associated with nuclear retention, but the cause-consequence relationship between hyperadenylation and regulation of RNA nuclear export is still unclear. We compared polyadenylation status between normal and expanded DMPK transcripts in muscle cells and tissues derived from unaffected individuals and patients with myotonic dystrophy type 1 (DM1). DM1 is an autosomal dominant disorder caused by (CTG)n repeat expansion in the DMPK gene. DM1 etiology is characterized by an almost complete block of nuclear export of DMPK transcripts carrying a long (CUG)n repeat, including aberrant sequestration of RNA-binding proteins. We show here by use of cell fractionation, RNA size separation and analysis of poly(A) tail length that a considerable fraction of transcripts from the normal DMPK allele is also retained in the nucleus (~30%). They carry poly(A) tails with an unusually broad length distribution, ranging between a few dozen to >500 adenosine residues. Remarkably, expanded DMPK (CUG)n transcripts from the mutant allele, almost exclusively nuclear, carry equally long poly(A) tails. Our findings thus suggest that nuclear retention may be a common feature of regulation of DMPK RNA expression. The typical forced nuclear residence of expanded DMPK transcripts affects this regulation in tissues of DM1 patients, but not through hyperadenylation.
Collapse
Affiliation(s)
- Anke E E G Gudde
- Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Department of Cell Biology, Nijmegen, The Netherlands
| | - Ingeborg D G van Kessel
- Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Department of Cell Biology, Nijmegen, The Netherlands
| | - Laurène M André
- Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Department of Cell Biology, Nijmegen, The Netherlands
| | - Bé Wieringa
- Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Department of Cell Biology, Nijmegen, The Netherlands
| | - Derick G Wansink
- Radboud University Medical Centre, Radboud Institute for Molecular Life Sciences, Department of Cell Biology, Nijmegen, The Netherlands.
| |
Collapse
|
37
|
Carvalho T, Martins S, Rino J, Marinho S, Carmo-Fonseca M. Pharmacological inhibition of the spliceosome subunit SF3b triggers exon junction complex-independent nonsense-mediated decay. J Cell Sci 2017; 130:1519-1531. [PMID: 28302904 DOI: 10.1242/jcs.202200] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 03/06/2017] [Indexed: 12/12/2022] Open
Abstract
Spliceostatin A, meayamycin, and pladienolide B are small molecules that target the SF3b subunit of the spliceosomal U2 small nuclear ribonucleoprotein (snRNP). These compounds are attracting much attention as tools to manipulate splicing and for use as potential anti-cancer drugs. We investigated the effects of these inhibitors on mRNA transport and stability in human cells. Upon splicing inhibition, unspliced pre-mRNAs accumulated in the nucleus, particularly within enlarged nuclear speckles. However, a small fraction of the pre-mRNA molecules were exported to the cytoplasm. We identified the export adaptor ALYREF as being associated with intron-containing transcripts and show its requirement for the nucleo-cytoplasmic transport of unspliced pre-mRNA. In contrast, the exon junction complex (EJC) core protein eIF4AIII failed to form a stable complex with intron-containing transcripts. Despite the absence of EJC, unspliced transcripts in the cytoplasm were degraded by nonsense-mediated decay (NMD), suggesting that unspliced transcripts are degraded by an EJC-independent NMD pathway. Collectively, our results indicate that although blocking the function of SF3b elicits a massive accumulation of unspliced pre-mRNAs in the nucleus, intron-containing transcripts can still bind the ALYREF export factor and be transported to the cytoplasm, where they trigger an alternative NMD pathway.
Collapse
Affiliation(s)
- Teresa Carvalho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - Sandra Martins
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - José Rino
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - Sérgio Marinho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa 1649-028, Portugal
| |
Collapse
|
38
|
Pocock GM, Zimdars LL, Yuan M, Eliceiri KW, Ahlquist P, Sherer NM. Diverse activities of viral cis-acting RNA regulatory elements revealed using multicolor, long-term, single-cell imaging. Mol Biol Cell 2017; 28:476-487. [PMID: 27903772 PMCID: PMC5341730 DOI: 10.1091/mbc.e16-08-0612] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 11/22/2016] [Accepted: 11/23/2016] [Indexed: 02/06/2023] Open
Abstract
Cis-acting RNA structural elements govern crucial aspects of viral gene expression. How these structures and other posttranscriptional signals affect RNA trafficking and translation in the context of single cells is poorly understood. Herein we describe a multicolor, long-term (>24 h) imaging strategy for measuring integrated aspects of viral RNA regulatory control in individual cells. We apply this strategy to demonstrate differential mRNA trafficking behaviors governed by RNA elements derived from three retroviruses (HIV-1, murine leukemia virus, and Mason-Pfizer monkey virus), two hepadnaviruses (hepatitis B virus and woodchuck hepatitis virus), and an intron-retaining transcript encoded by the cellular NXF1 gene. Striking behaviors include "burst" RNA nuclear export dynamics regulated by HIV-1's Rev response element and the viral Rev protein; transient aggregations of RNAs into discrete foci at or near the nuclear membrane triggered by multiple elements; and a novel, pulsiform RNA export activity regulated by the hepadnaviral posttranscriptional regulatory element. We incorporate single-cell tracking and a data-mining algorithm into our approach to obtain RNA element-specific, high-resolution gene expression signatures. Together these imaging assays constitute a tractable, systems-based platform for studying otherwise difficult to access spatiotemporal features of viral and cellular gene regulation.
Collapse
MESH Headings
- Active Transport, Cell Nucleus/physiology
- Cell Nucleus/metabolism
- Gene Expression Regulation, Viral
- Gene Products, rev/metabolism
- Genes, env/physiology
- HIV-1
- Mason-Pfizer monkey virus
- Molecular Imaging/methods
- RNA Processing, Post-Transcriptional/physiology
- RNA, Messenger/metabolism
- RNA, Viral
- Regulatory Sequences, Nucleic Acid/genetics
- Regulatory Sequences, Nucleic Acid/physiology
- Regulatory Sequences, Ribonucleic Acid/genetics
- Regulatory Sequences, Ribonucleic Acid/physiology
- Single-Cell Analysis/methods
Collapse
Affiliation(s)
- Ginger M Pocock
- McArdle Laboratory for Cancer Research and Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706
| | - Laraine L Zimdars
- McArdle Laboratory for Cancer Research and Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706
| | - Ming Yuan
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706
- Department of Statistics, University of Wisconsin-Madison, Madison, WI 53706
| | - Kevin W Eliceiri
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706
- Laboratory for Optical and Computational Instrumentation and Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706
| | - Paul Ahlquist
- McArdle Laboratory for Cancer Research and Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53706
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI 53706
| | - Nathan M Sherer
- McArdle Laboratory for Cancer Research and Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI 53706
| |
Collapse
|
39
|
Nuclear Export Signal Masking Regulates HIV-1 Rev Trafficking and Viral RNA Nuclear Export. J Virol 2017; 91:JVI.02107-16. [PMID: 27852860 DOI: 10.1128/jvi.02107-16] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 11/14/2016] [Indexed: 12/28/2022] Open
Abstract
HIV-1's Rev protein forms a homo-oligomeric adaptor complex linking viral RNAs to the cellular CRM1/Ran-GTP nuclear export machinery through the activity of Rev's prototypical leucine-rich nuclear export signal (NES). In this study, we used a functional fluorescently tagged Rev fusion protein as a platform to study the effects of modulating Rev NES identity, number, position, or strength on Rev subcellular trafficking, viral RNA nuclear export, and infectious virion production. We found that Rev activity was remarkably tolerant of diverse NES sequences, including supraphysiological NES (SNES) peptides that otherwise arrest CRM1 transport complexes at nuclear pores. Rev's ability to tolerate a SNES was both position and multimerization dependent, an observation consistent with a model wherein Rev self-association acts to transiently mask the NES peptide(s), thereby biasing Rev's trafficking into the nucleus. Combined imaging and functional assays also indicated that NES masking underpins Rev's well-known tendency to accumulate at the nucleolus, as well as Rev's capacity to activate optimal levels of late viral gene expression. We propose that Rev multimerization and NES masking regulates Rev's trafficking to and retention within the nucleus even prior to RNA binding. IMPORTANCE HIV-1 infects more than 34 million people worldwide causing >1 million deaths per year. Infectious virion production is activated by the essential viral Rev protein that mediates nuclear export of intron-bearing late-stage viral mRNAs. Rev's shuttling into and out of the nucleus is regulated by the antagonistic activities of both a peptide-encoded N-terminal nuclear localization signal and C-terminal nuclear export signal (NES). How Rev and related viral proteins balance strong import and export activities in order to achieve optimal levels of viral gene expression is incompletely understood. We provide evidence that multimerization provides a mechanism by which Rev transiently masks its NES peptide, thereby biasing its trafficking to and retention within the nucleus. Targeted pharmacological disruption of Rev-Rev interactions should perturb multiple Rev activities, both Rev-RNA binding and Rev's trafficking to the nucleus in the first place.
Collapse
|
40
|
Heinrich S, Derrer CP, Lari A, Weis K, Montpetit B. Temporal and spatial regulation of mRNA export: Single particle RNA-imaging provides new tools and insights. Bioessays 2017; 39. [PMID: 28052353 DOI: 10.1002/bies.201600124] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The transport of messenger RNAs (mRNAs) from the nucleus to cytoplasm is an essential step in the gene expression program of all eukaryotes. Recent technological advances in the areas of RNA-labeling, microscopy, and sequencing are leading to novel insights about mRNA biogenesis and export. This includes quantitative single molecule imaging (SMI) of RNA molecules in live cells, which is providing knowledge of the spatial and temporal dynamics of the export process. As this information becomes available, it leads to new questions, the reinterpretation of previous findings, and revised models of mRNA export. In this review, we will briefly highlight some of these recent findings and discuss how live cell SMI approaches may be used to further our current understanding of mRNA export and gene expression.
Collapse
Affiliation(s)
| | | | - Azra Lari
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | - Karsten Weis
- Institute of Biochemistry, ETH Zurich, Zurich, Switzerland
| | - Ben Montpetit
- Department of Cell Biology, University of Alberta, Edmonton, Canada.,Department of Viticulture and Enology, University of California, Davis, CA, USA
| |
Collapse
|
41
|
Abstract
RNA-binding proteins play a variety of roles in cellular physiology. Some regulate mRNA processing, mRNA abundance, and translation efficiency. Some fight off invader RNA through small RNA-driven silencing pathways. Others sense foreign sequences in the form of double-stranded RNA and activate the innate immune response. Yet others, for example cytoplasmic aconitase, act as bi-functional proteins, processing metabolites in one conformation and regulating metabolic gene expression in another. Not all are involved in gene regulation. Some play structural roles, for example, connecting the translational machinery to the endoplasmic reticulum outer membrane. Despite their pervasive role and relative importance, it has remained difficult to identify new RNA-binding proteins in a systematic, unbiased way. A recent body of literature from several independent labs has defined robust, easily adaptable protocols for mRNA interactome discovery. In this review, I summarize the methods and review some of the intriguing findings from their application to a wide variety of biological systems.
Collapse
Affiliation(s)
- Sean P Ryder
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| |
Collapse
|
42
|
Diot C, Fournier G, Dos Santos M, Magnus J, Komarova A, van der Werf S, Munier S, Naffakh N. Influenza A Virus Polymerase Recruits the RNA Helicase DDX19 to Promote the Nuclear Export of Viral mRNAs. Sci Rep 2016; 6:33763. [PMID: 27653209 PMCID: PMC5037575 DOI: 10.1038/srep33763] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 09/01/2016] [Indexed: 12/16/2022] Open
Abstract
Enhancing the knowledge of host factors that are required for efficient influenza A virus (IAV) replication is essential to address questions related to pathogenicity and to identify targets for antiviral drug development. Here we focused on the interplay between IAV and DExD-box RNA helicases (DDX), which play a key role in cellular RNA metabolism by remodeling RNA-RNA or RNA-protein complexes. We performed a targeted RNAi screen on 35 human DDX proteins to identify those involved in IAV life cycle. DDX19 was a major hit. In DDX19-depleted cells the accumulation of viral RNAs and proteins was delayed, and the production of infectious IAV particles was strongly reduced. We show that DDX19 associates with intronless, unspliced and spliced IAV mRNAs and promotes their nuclear export. In addition, we demonstrate an RNA-independent association between DDX19 and the viral polymerase, that is modulated by the ATPase activity of DDX19. Our results provide a model in which DDX19 is recruited to viral mRNAs in the nucleus of infected cells to enhance their nuclear export. Information gained from this virus-host interaction improves the understanding of both the IAV replication cycle and the cellular function of DDX19.
Collapse
Affiliation(s)
- Cédric Diot
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Guillaume Fournier
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Mélanie Dos Santos
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Julie Magnus
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Anastasia Komarova
- CNRS, UMR3569, F-75015 Paris, France.,Institut Pasteur, Unité de Génomique Virale et Vaccination, Département de Virologie, F-75015 Paris, France
| | - Sylvie van der Werf
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Sandie Munier
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| | - Nadia Naffakh
- Institut Pasteur, Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, F-75015 Paris, France.,CNRS, UMR3569, F-75015 Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, Unité de Génétique Moléculaire des Virus à ARN, EA302, F-75015 Paris, France
| |
Collapse
|
43
|
Watkinson RE, Lee B. Nipah virus matrix protein: expert hacker of cellular machines. FEBS Lett 2016; 590:2494-511. [PMID: 27350027 DOI: 10.1002/1873-3468.12272] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 06/20/2016] [Accepted: 06/26/2016] [Indexed: 12/12/2022]
Abstract
Nipah virus (NiV, Henipavirus) is a highly lethal emergent zoonotic paramyxovirus responsible for repeated human outbreaks of encephalitis in South East Asia. There are no approved vaccines or treatments, thus improved understanding of NiV biology is imperative. NiV matrix protein recruits a plethora of cellular machinery to scaffold and coordinate virion budding. Intriguingly, matrix also hijacks cellular trafficking and ubiquitination pathways to facilitate transient nuclear localization. While the biological significance of matrix nuclear localization for an otherwise cytoplasmic virus remains enigmatic, the molecular details have begun to be characterized, and are conserved among matrix proteins from divergent paramyxoviruses. Matrix protein appropriation of cellular machinery will be discussed in terms of its early nuclear targeting and later role in virion assembly.
Collapse
Affiliation(s)
- Ruth E Watkinson
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Benhur Lee
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
44
|
Ben-Yishay R, Ashkenazy AJ, Shav-Tal Y. Dynamic Encounters of Genes and Transcripts with the Nuclear Pore. Trends Genet 2016; 32:419-431. [DOI: 10.1016/j.tig.2016.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/20/2016] [Indexed: 01/04/2023]
|
45
|
HIV-1 and M-PMV RNA Nuclear Export Elements Program Viral Genomes for Distinct Cytoplasmic Trafficking Behaviors. PLoS Pathog 2016; 12:e1005565. [PMID: 27070420 PMCID: PMC4829213 DOI: 10.1371/journal.ppat.1005565] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/21/2016] [Indexed: 12/15/2022] Open
Abstract
Retroviruses encode cis-acting RNA nuclear export elements that override nuclear retention of intron-containing viral mRNAs including the full-length, unspliced genomic RNAs (gRNAs) packaged into assembling virions. The HIV-1 Rev-response element (RRE) recruits the cellular nuclear export receptor CRM1 (also known as exportin-1/XPO1) using the viral protein Rev, while simple retroviruses encode constitutive transport elements (CTEs) that directly recruit components of the NXF1(Tap)/NXT1(p15) mRNA nuclear export machinery. How gRNA nuclear export is linked to trafficking machineries in the cytoplasm upstream of virus particle assembly is unknown. Here we used long-term (>24 h), multicolor live cell imaging to directly visualize HIV-1 gRNA nuclear export, translation, cytoplasmic trafficking, and virus particle production in single cells. We show that the HIV-1 RRE regulates unique, en masse, Rev- and CRM1-dependent "burst-like" transitions of mRNAs from the nucleus to flood the cytoplasm in a non-localized fashion. By contrast, the CTE derived from Mason-Pfizer monkey virus (M-PMV) links gRNAs to microtubules in the cytoplasm, driving them to cluster markedly to the centrosome that forms the pericentriolar core of the microtubule-organizing center (MTOC). Adding each export element to selected heterologous mRNAs was sufficient to confer each distinct export behavior, as was directing Rev/CRM1 or NXF1/NXT1 transport modules to mRNAs using a site-specific RNA tethering strategy. Moreover, multiple CTEs per transcript enhanced MTOC targeting, suggesting that a cooperative mechanism links NXF1/NXT1 to microtubules. Combined, these results reveal striking, unexpected features of retroviral gRNA nucleocytoplasmic transport and demonstrate roles for mRNA export elements that extend beyond nuclear pores to impact gRNA distribution in the cytoplasm.
Collapse
|
46
|
Musser SM, Grünwald D. Deciphering the Structure and Function of Nuclear Pores Using Single-Molecule Fluorescence Approaches. J Mol Biol 2016; 428:2091-119. [PMID: 26944195 DOI: 10.1016/j.jmb.2016.02.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 01/05/2016] [Accepted: 02/17/2016] [Indexed: 01/06/2023]
Abstract
Due to its central role in macromolecular trafficking and nucleocytoplasmic information transfer, the nuclear pore complex (NPC) has been studied in great detail using a wide spectrum of methods. Consequently, many aspects of its architecture, general function, and role in the life cycle of a cell are well understood. Over the last decade, fluorescence microscopy methods have enabled the real-time visualization of single molecules interacting with and transiting through the NPC, allowing novel questions to be examined with nanometer precision. While initial single-molecule studies focused primarily on import pathways using permeabilized cells, it has recently proven feasible to investigate the export of mRNAs in living cells. Single-molecule assays can address questions that are difficult or impossible to answer by other means, yet the complexity of nucleocytoplasmic transport requires that interpretation be based on a firm genetic, biochemical, and structural foundation. Moreover, conceptually simple single-molecule experiments remain technically challenging, particularly with regard to signal intensity, signal-to-noise ratio, and the analysis of noise, stochasticity, and precision. We discuss nuclear transport issues recently addressed by single-molecule microscopy, evaluate the limits of existing assays and data, and identify open questions for future studies. We expect that single-molecule fluorescence approaches will continue to be applied to outstanding nucleocytoplasmic transport questions, and that the approaches developed for NPC studies are extendable to additional complex systems and pathways within cells.
Collapse
Affiliation(s)
- Siegfried M Musser
- Department of Molecular and Cellular Medicine, College of Medicine, The Texas A&M Health Science Center, 1114 TAMU, College Station, TX 77843, USA.
| | - David Grünwald
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA.
| |
Collapse
|
47
|
Björk P, Persson JO, Wieslander L. Intranuclear binding in space and time of exon junction complex and NXF1 to premRNPs/mRNPs in vivo. J Cell Biol 2016; 211:63-75. [PMID: 26459599 PMCID: PMC4602041 DOI: 10.1083/jcb.201412017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The exon junction core complex associates with Balbiani ring (BR) premRNPs during transcription and in relation to splicing, whereas the export factor NXF1 is recruited in the interchromatin, and BR mRNPs become export competent only after passage through the interchromatin. Eukaryotic gene expression requires the ordered association of numerous factors with precursor messenger RNAs (premRNAs)/messenger RNAs (mRNAs) to achieve efficiency and regulation. Here, we use the Balbiani ring (BR) genes to demonstrate the temporal and spatial association of the exon junction complex (EJC) core with gene-specific endogenous premRNAs and mRNAs. The EJC core components bind cotranscriptionally to BR premRNAs during or very rapidly after splicing. The EJC core does not recruit the nonsense-mediated decay mediaters UPF2 and UPF3 until the BR messenger RNA protein complexes (mRNPs) enter the interchromatin. Even though several known adapters for the export factor NXF1 become part of BR mRNPs already at the gene, NXF1 binds to BR mRNPs only in the interchromatin. In steady state, a subset of the BR mRNPs in the interchromatin binds NXF1, UPF2, and UPF3. This binding appears to occur stochastically, and the efficiency approximately equals synthesis and export of the BR mRNPs. Our data provide unique in vivo information on how export competent eukaryotic mRNPs are formed.
Collapse
Affiliation(s)
- Petra Björk
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Jan-Olov Persson
- Department of Mathematics, Stockholm University, SE-106 91 Stockholm, Sweden
| | - Lars Wieslander
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-106 91 Stockholm, Sweden
| |
Collapse
|
48
|
Stankovic N, Schloesser M, Joris M, Sauvage E, Hanikenne M, Motte P. Dynamic Distribution and Interaction of the Arabidopsis SRSF1 Subfamily Splicing Factors. PLANT PHYSIOLOGY 2016; 170:1000-13. [PMID: 26697894 PMCID: PMC4734559 DOI: 10.1104/pp.15.01338] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/19/2015] [Indexed: 05/19/2023]
Abstract
Ser/Arg-rich (SR) proteins are essential nucleus-localized splicing factors. Our prior studies showed that Arabidopsis (Arabidopsis thaliana) RSZ22, a homolog of the human SRSF7 SR factor, exits the nucleus through two pathways, either dependent or independent on the XPO1 receptor. Here, we examined the expression profiles and shuttling dynamics of the Arabidopsis SRSF1 subfamily (SR30, SR34, SR34a, and SR34b) under control of their endogenous promoter in Arabidopsis and in transient expression assay. Due to its rapid nucleocytoplasmic shuttling and high expression level in transient assay, we analyzed the multiple determinants that regulate the localization and shuttling dynamics of SR34. By site-directed mutagenesis of SR34 RNA-binding sequences and Arg/Ser-rich (RS) domain, we further show that functional RRM1 or RRM2 are dispensable for the exclusive protein nuclear localization and speckle-like distribution. However, mutations of both RRMs induced aggregation of the protein whereas mutation in the RS domain decreased the stability of the protein and suppressed its nuclear accumulation. Furthermore, the RNA-binding motif mutants are defective for their export through the XPO1 (CRM1/Exportin-1) receptor pathway, but retain nucleocytoplasmic mobility. We performed a yeast two hybrid screen with SR34 as bait and discovered SR45 as a new interactor. SR45 is an unusual SR splicing factor bearing two RS domains. These interactions were confirmed in planta by FLIM-FRET and BiFC and the roles of SR34 domains in protein-protein interactions were further studied. Altogether, our report extends our understanding of shuttling dynamics of Arabidopsis SR splicing factors.
Collapse
Affiliation(s)
- Nancy Stankovic
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| | - Marie Schloesser
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| | - Marine Joris
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| | - Eric Sauvage
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| | - Marc Hanikenne
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| | - Patrick Motte
- Laboratory of Functional Genomics and Plant Molecular Imaging (N.S., M.S., M.J., M.H., P.M.), Laboratory of Macromolecular Crystallography (E.S.), PhytoSYSTEMS (M.H., P.M.), Centre for Protein Engineering (CIP; N.S., M.S., M.J., E.S., M.H., P.M.), Department of Life Sciences, and Centre for Assistance in Technology of Microscopy (CATM; P.M.), University of Liège, B-4000 Liège, Belgium
| |
Collapse
|
49
|
Carter-O'Connell I, Jin H, Morgan RK, Zaja R, David LL, Ahel I, Cohen MS. Identifying Family-Member-Specific Targets of Mono-ARTDs by Using a Chemical Genetics Approach. Cell Rep 2016; 14:621-631. [PMID: 26774478 DOI: 10.1016/j.celrep.2015.12.045] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 10/10/2015] [Accepted: 12/04/2015] [Indexed: 02/07/2023] Open
Abstract
ADP-ribosyltransferases (ARTD1-16) have emerged as major downstream effectors of NAD(+) signaling in the cell. Most ARTDs (ARTD7 and 8, 10-12, and 14-17) catalyze the transfer of a single unit of ADP-ribose from NAD(+) to target proteins, a process known as mono-ADP-ribosylation (MARylation). Progress in understanding the cellular functions of MARylation has been limited by the inability to identify the direct targets for individual mono-ARTDs. Here, we engineered mono-ARTDs to use an NAD(+) analog that is orthogonal to wild-type ARTDs. We profiled the MARylomes of ARTD10 and ARTD11 in vitro, identifying isoform-specific targets and revealing a potential role for ARTD11 in nuclear pore complex biology. We found that ARTD11 targeting is dependent on both its regulatory and catalytic domains, which has important implications for how ARTDs recognize their targets. We anticipate that our chemical genetic strategy will be generalizable to all mono-ARTD family members based on the similarity of the mono-ARTD catalytic domains.
Collapse
Affiliation(s)
- Ian Carter-O'Connell
- Program in Chemical Biology and Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97210, USA
| | - Haihong Jin
- Program in Chemical Biology and Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97210, USA
| | - Rory K Morgan
- Program in Chemical Biology and Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97210, USA
| | - Roko Zaja
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Larry L David
- Department of Biochemistry, Oregon Health and Science University, Portland, OR 97210, USA
| | - Ivan Ahel
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Michael S Cohen
- Program in Chemical Biology and Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97210, USA.
| |
Collapse
|
50
|
Weberruss M, Antonin W. Perforating the nuclear boundary – how nuclear pore complexes assemble. J Cell Sci 2016; 129:4439-4447. [DOI: 10.1242/jcs.194753] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
ABSTRACT
The nucleus is enclosed by the nuclear envelope, a double membrane which creates a selective barrier between the cytoplasm and the nuclear interior. Its barrier and transport characteristics are determined by nuclear pore complexes (NPCs) that are embedded within the nuclear envelope, and control molecular exchange between the cytoplasm and nucleoplasm. In this Commentary, we discuss the biogenesis of these huge protein assemblies from approximately one thousand individual proteins. We will summarize current knowledge about distinct assembly modes in animal cells that are characteristic for different cell cycle phases and their regulation.
Collapse
Affiliation(s)
- Marion Weberruss
- Friedrich Miescher Laboratory of the Max Planck Society, Spemannstraße 39, Tübingen 72076, Germany
| | - Wolfram Antonin
- Friedrich Miescher Laboratory of the Max Planck Society, Spemannstraße 39, Tübingen 72076, Germany
| |
Collapse
|