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Dai W, Liu Z, Yan M, Nian X, Hong F, Zhou Z, Wang C, Fu X, Li X, Jiang M, Zhu Y, Huang Q, Lu X, Hou L, Yan N, Wang Q, Hu J, Mo W, Zhang X, Zhang L. Nucleoporin Seh1 controls murine neocortical development via transcriptional repression of p21 in neural stem cells. Dev Cell 2024; 59:482-495.e6. [PMID: 38272027 DOI: 10.1016/j.devcel.2024.01.002] [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: 11/08/2022] [Revised: 06/21/2023] [Accepted: 01/05/2024] [Indexed: 01/27/2024]
Abstract
Mutations or dysregulation of nucleoporins (Nups) are strongly associated with neural developmental diseases, yet the underlying mechanisms remain poorly understood. Here, we show that depletion of Nup Seh1 in radial glial progenitors results in defective neural progenitor proliferation and differentiation that ultimately manifests in impaired neurogenesis and microcephaly. This loss of stem cell proliferation is not associated with defects in the nucleocytoplasmic transport. Rather, transcriptome analysis showed that ablation of Seh1 in neural stem cells derepresses the expression of p21, and knockdown of p21 partially restored self-renewal capacity. Mechanistically, Seh1 cooperates with the NuRD transcription repressor complex at the nuclear periphery to regulate p21 expression. Together, these findings identified that Nups regulate brain development by exerting a chromatin-associated role and affecting neural stem cell proliferation.
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Affiliation(s)
- Wenxiu Dai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Zhixiong Liu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; Guangdong Institute of Intelligence Science and Technology, Hengqin, Zhuhai 519031, China
| | - Minbiao Yan
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Ximing Nian
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Fan Hong
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Zhihao Zhou
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Chaomeng Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Xing Fu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Xuewen Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Mengyun Jiang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Yanqin Zhu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Qiuying Huang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Xiaoyun Lu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Lichao Hou
- Department of Anesthesiology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361102, Fujian, China
| | - Ning Yan
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Qin Wang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jin Hu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China
| | - Wei Mo
- Sir Run Run Shaw Hospital, Department of Immunology, School of Basic Medical Science, Zhejiang University School of Medicine, Hangzhou 310058, China; Liangzhu Laboratory, Hangzhou 311121, China
| | - Xueqin Zhang
- Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Xiamen University, Xiamen 361102, Fujian, China
| | - Liang Zhang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Department of Neuroscience, the First Affiliated Hospital, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen 361102, Fujian, China; Department of Gynaecology and Obstetrics, Women and Children's Hospital Affiliated to Xiamen University, Xiamen University, Xiamen 361102, Fujian, China.
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2
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Choudhry SK, Neal ML, Li S, Navare AT, Van Eeuwen T, Wozniak RW, Mast FD, Rout MP, Aitchison JD. Nuclear pore complexes mediate subtelomeric gene silencing by regulating PCNA levels on chromatin. J Cell Biol 2023; 222:e202207060. [PMID: 37358474 PMCID: PMC10292210 DOI: 10.1083/jcb.202207060] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 04/02/2023] [Accepted: 06/07/2023] [Indexed: 06/27/2023] Open
Abstract
The nuclear pore complex (NPC) physically interacts with chromatin and regulates gene expression. The Saccharomyces cerevisiae inner ring nucleoporin Nup170 has been implicated in chromatin organization and the maintenance of gene silencing in subtelomeric regions. To gain insight into how Nup170 regulates this process, we used protein-protein interactions, genetic interactions, and transcriptome correlation analyses to identify the Ctf18-RFC complex, an alternative proliferating cell nuclear antigen (PCNA) loader, as a facilitator of the gene regulatory functions of Nup170. The Ctf18-RFC complex is recruited to a subpopulation of NPCs that lack the nuclear basket proteins Mlp1 and Mlp2. In the absence of Nup170, PCNA levels on DNA are reduced, resulting in the loss of silencing of subtelomeric genes. Increasing PCNA levels on DNA by removing Elg1, which is required for PCNA unloading, rescues subtelomeric silencing defects in nup170Δ. The NPC, therefore, mediates subtelomeric gene silencing by regulating PCNA levels on DNA.
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Affiliation(s)
- Sanjeev Kumar Choudhry
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Maxwell L. Neal
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Song Li
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Arti T. Navare
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Trevor Van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | | | - Fred D. Mast
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
| | - John D. Aitchison
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA, USA
- Departments of Pediatrics and Biochemistry, University of Washington, Seattle, WA, USA
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3
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Ye X, Guan M, Guo Y, Liu X, Wang K, Chen T, Zhao S, Chen L. Live-cell super-resolution imaging unconventional dynamics and assemblies of nuclear pore complexes. BIOPHYSICS REPORTS 2023; 9:206-214. [PMID: 38516621 PMCID: PMC10951474 DOI: 10.52601/bpr.2023.230010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 11/21/2023] [Indexed: 03/23/2024] Open
Abstract
Super-resolution microscopy has promoted the development of cell biology, but imaging proteins with low copy numbers in cellular structures remains challenging. The limited number of designated proteins within nuclear pore complexes (NPCs) impedes continuous observation in live cells, although they are often used as a standard for evaluating various SR methods. To address this issue, we tagged POM121 with Halo-SiR and imaged it using structured illumination microscopy with sparse deconvolution (Sparse-SIM). Remarkably, POM121-SiR exhibited more than six-fold fluorescence intensity and four-fold enhanced contrast compared to the same protein labeled with tandem-linked mCherry, while showing negligible photo-bleaching during SR imaging for 200 frames. Using this technique, we discovered various types of NPCs, including ring-like and cluster-like structures, and observed dynamic remodeling along with the sequential appearance of different Nup compositions. Overall, Halo-SiR with Sparse-SIM is a potent tool for extended SR imaging of dynamic structures of NPCs in live cells, and it may also help visualize proteins with limited numbers in general.
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Affiliation(s)
- Xianxin Ye
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Minzhu Guan
- Key Laboratory of Laser Life Science, Ministry of Education, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Yaorong Guo
- Key Laboratory of Laser Life Science, Ministry of Education, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Xiang Liu
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Kunhao Wang
- Key Laboratory of Laser Life Science, Ministry of Education, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Tongsheng Chen
- Key Laboratory of Laser Life Science, Ministry of Education, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Shiqun Zhao
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Liangyi Chen
- National Biomedical Imaging Center, State Key Laboratory of Membrane Biology, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Beijing 100871, China
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4
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Saik NO, Ptak C, Rehman S, Aitchison JD, Montpetit B, Wozniak RW. SUMOylation at the inner nuclear membrane facilitates nuclear envelope biogenesis during mitosis. J Cell Biol 2023; 222:e202208137. [PMID: 37398994 PMCID: PMC10318406 DOI: 10.1083/jcb.202208137] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 03/24/2023] [Accepted: 05/15/2023] [Indexed: 07/04/2023] Open
Abstract
As eukaryotic cells progress through cell division, the nuclear envelope (NE) membrane must expand to accommodate the formation of progeny nuclei. In Saccharomyces cerevisiae, closed mitosis allows visualization of NE biogenesis during mitosis. During this period, the SUMO E3 ligase Siz2 binds the inner nuclear membrane (INM) and initiates a wave of INM protein SUMOylation. Here, we show these events increase INM levels of phosphatidic acid (PA), an intermediate of phospholipid biogenesis, and are necessary for normal mitotic NE membrane expansion. The increase in INM PA is driven by the Siz2-mediated inhibition of the PA phosphatase Pah1. During mitosis, this results from the binding of Siz2 to the INM and dissociation of Spo7 and Nem1, a complex required for the activation of Pah1. As cells enter interphase, the process is then reversed by the deSUMOylase Ulp1. This work further establishes a central role for temporally controlled INM SUMOylation in coordinating processes, including membrane expansion, that regulate NE biogenesis during mitosis.
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Affiliation(s)
- Natasha O. Saik
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Christopher Ptak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Saif Rehman
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - John D. Aitchison
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
- Seattle Children’s Research Institute, Seattle, WA, USA
- Department of Pediatrics and Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Ben Montpetit
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
- Department of Viticulture and Enology, University of California Davis, Davis, CA, USA
| | - Richard W. Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
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5
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Oses C, De Rossi MC, Bruno L, Verneri P, Diaz MC, Benítez B, Guberman A, Levi V. From the membrane to the nucleus: mechanical signals and transcription regulation. Biophys Rev 2023; 15:671-683. [PMID: 37681098 PMCID: PMC10480138 DOI: 10.1007/s12551-023-01103-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/20/2023] [Indexed: 09/09/2023] Open
Abstract
Mechanical forces drive and modulate a wide variety of processes in eukaryotic cells including those occurring in the nucleus. Relevantly, forces are fundamental during development since they guide lineage specifications of embryonic stem cells. A sophisticated macromolecular machinery transduces mechanical stimuli received at the cell surface into a biochemical output; a key component in this mechanical communication is the cytoskeleton, a complex network of biofilaments in constant remodeling that links the cell membrane to the nuclear envelope. Recent evidence highlights that forces transmitted through the cytoskeleton directly affect the organization of chromatin and the accessibility of transcription-related molecules to their targets in the DNA. Consequently, mechanical forces can directly modulate transcription and change gene expression programs. Here, we will revise the biophysical toolbox involved in the mechanical communication with the cell nucleus and discuss how mechanical forces impact on the organization of this organelle and more specifically, on transcription. We will also discuss how live-cell fluorescence imaging is producing exquisite information to understand the mechanical response of cells and to quantify the landscape of interactions of transcription factors with chromatin in embryonic stem cells. These studies are building new biophysical insights that could be fundamental to achieve the goal of manipulating forces to guide cell differentiation in culture systems.
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Affiliation(s)
- Camila Oses
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - María Cecilia De Rossi
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - Luciana Bruno
- Facultad de Ciencias Exactas Y Naturales, Instituto de Cálculo (IC), CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - Paula Verneri
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - María Candelaria Diaz
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - Belén Benítez
- Instituto de Fisiología, Biología Molecular Y Neurociencias (IFIBYNE), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
| | - Alejandra Guberman
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
- Facultad de Ciencias Exactas Y Naturales, Departamento de Fisiología, Universidad de Buenos Aires, Biología Molecular Y Celular, C1428EGA Buenos Aires, Argentina
| | - Valeria Levi
- Instituto de Química Biológica de La Facultad de Ciencias Exactas Y Naturales (IQUIBICEN), Facultad de Ciencias Exactas Y Naturales, CONICET-Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
- Facultad de Ciencias Exactas Y Naturales, Departamento de Química Biológica, Universidad de Buenos Aires, C1428EGA Buenos Aires, Argentina
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6
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Sing TL, Brar GA, Ünal E. Gametogenesis: Exploring an Endogenous Rejuvenation Program to Understand Cellular Aging and Quality Control. Annu Rev Genet 2022; 56:89-112. [PMID: 35878627 PMCID: PMC9712276 DOI: 10.1146/annurev-genet-080320-025104] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Gametogenesis is a conserved developmental program whereby a diploid progenitor cell differentiates into haploid gametes, the precursors for sexually reproducing organisms. In addition to ploidy reduction and extensive organelle remodeling, gametogenesis naturally rejuvenates the ensuing gametes, leading to resetting of life span. Excitingly, ectopic expression of the gametogenesis-specific transcription factor Ndt80 is sufficient to extend life span in mitotically dividing budding yeast, suggesting that meiotic rejuvenation pathways can be repurposed outside of their natural context. In this review, we highlight recent studies of gametogenesis that provide emerging insight into natural quality control, organelle remodeling, and rejuvenation strategies that exist within a cell. These include selective inheritance, programmed degradation, and de novo synthesis, all of which are governed by the meiotic gene expression program entailing many forms of noncanonical gene regulation. Finally, we highlight critical questions that remain in the field and provide perspective on the implications of gametogenesis research on human health span.
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Affiliation(s)
- Tina L Sing
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA;
| | - Gloria A Brar
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA;
| | - Elçin Ünal
- Department of Molecular and Cell Biology, University of California, Berkeley, California, USA;
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7
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Dutta S, Polavaram NS, Islam R, Bhattacharya S, Bodas S, Mayr T, Roy S, Albala SAY, Toma MI, Darehshouri A, Borkowetz A, Conrad S, Fuessel S, Wirth M, Baretton GB, Hofbauer LC, Ghosh P, Pienta KJ, Klinkebiel DL, Batra SK, Muders MH, Datta K. Neuropilin-2 regulates androgen-receptor transcriptional activity in advanced prostate cancer. Oncogene 2022; 41:3747-3760. [PMID: 35754042 PMCID: PMC9979947 DOI: 10.1038/s41388-022-02382-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 06/03/2022] [Accepted: 06/10/2022] [Indexed: 01/22/2023]
Abstract
Aberrant transcriptional activity of androgen receptor (AR) is one of the dominant mechanisms for developing of castration-resistant prostate cancer (CRPC). Analyzing AR-transcriptional complex related to CRPC is therefore important towards understanding the mechanism of therapy resistance. While studying its mechanism, we observed that a transmembrane protein called neuropilin-2 (NRP2) plays a contributory role in forming a novel AR-transcriptional complex containing nuclear pore proteins. Using immunogold electron microscopy, high-resolution confocal microscopy, chromatin immunoprecipitation, proteomics, and other biochemical techniques, we delineated the molecular mechanism of how a specific splice variant of NRP2 becomes sumoylated upon ligand stimulation and translocates to the inner nuclear membrane. This splice variant of NRP2 then stabilizes the complex between AR and nuclear pore proteins to promote CRPC specific gene expression. Both full-length and splice variants of AR have been identified in this specific transcriptional complex. In vitro cell line-based assays indicated that depletion of NRP2 not only destabilizes the AR-nuclear pore protein interaction but also inhibits the transcriptional activities of AR. Using an in vivo bone metastasis model, we showed that the inhibition of NRP2 led to the sensitization of CRPC cells toward established anti-AR therapies such as enzalutamide. Overall, our finding emphasize the importance of combinatorial inhibition of NRP2 and AR as an effective therapeutic strategy against treatment refractory prostate cancer.
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Affiliation(s)
- Samikshan Dutta
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA.
| | - Navatha Shree Polavaram
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Ridwan Islam
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Sreyashi Bhattacharya
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Sanika Bodas
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Thomas Mayr
- Rudolf Becker Laboratory for Prostate Cancer Research, Medical Faculty, University of Bonn, Germany,Institute of Pathology, Medical Faculty, University of Bonn, Germany,Institute of Pathology, Technische Universitaet Dresden, Dresden, Germany
| | - Sohini Roy
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | | | - Marieta I. Toma
- Institute of Pathology, Medical Faculty, University of Bonn, Germany,Institute of Pathology, Technische Universitaet Dresden, Dresden, Germany
| | - Anza Darehshouri
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Angelika Borkowetz
- Department of Urology, Technische Universitaet Dresden, Dresden, Germany
| | - Stefanie Conrad
- Division of Endocrinology and Metabolic Bone Diseases, Department of Medicine III, Technische Universitaet Dresden, Dresden, Germany,Center for Healthy Aging, Technische Universitaet Dresden, Dresden, Germany
| | - Susanne Fuessel
- Department of Urology, Technische Universitaet Dresden, Dresden, Germany
| | - Manfred Wirth
- Department of Urology, Technische Universitaet Dresden, Dresden, Germany
| | - Gustavo B. Baretton
- Institute of Pathology, Technische Universitaet Dresden, Dresden, Germany,German Cancer Consortium (DKTK), partner site Dresden and German Research Center (DKFZ), Heidelberg, Germany,Tumor and Normal Tissue Bank of the University Cancer Center (UCC), University Hospital and Faculty of Medicine, Technische Universitaet Dresden, Germany
| | - Lorenz C. Hofbauer
- Division of Endocrinology and Metabolic Bone Diseases, Department of Medicine III, Technische Universitaet Dresden, Dresden, Germany,Center for Healthy Aging, Technische Universitaet Dresden, Dresden, Germany,German Cancer Consortium (DKTK), partner site Dresden and German Research Center (DKFZ), Heidelberg, Germany
| | - Paramita Ghosh
- Department of Biochemistry and Molecular Medicine, University of California Davis
| | - Kenneth J. Pienta
- The Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David L Klinkebiel
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Surinder K. Batra
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Michael H. Muders
- Rudolf Becker Laboratory for Prostate Cancer Research, Medical Faculty, University of Bonn, Germany,Institute of Pathology, Medical Faculty, University of Bonn, Germany,Institute of Pathology, Technische Universitaet Dresden, Dresden, Germany
| | - Kaustubh Datta
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA.
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8
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Li Z, Chen S, Zhao L, Huang G, Pi X, Sun S, Wang P, Sui SF. Near-atomic structure of the inner ring of the Saccharomyces cerevisiae nuclear pore complex. Cell Res 2022; 32:437-450. [PMID: 35301440 PMCID: PMC9061825 DOI: 10.1038/s41422-022-00632-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 02/08/2022] [Indexed: 12/17/2022] Open
Abstract
Nuclear pore complexes (NPCs) mediate bidirectional nucleocytoplasmic transport of substances in eukaryotic cells. However, the accurate molecular arrangement of NPCs remains enigmatic owing to their huge size and highly dynamic nature. Here we determined the structure of the asymmetric unit of the inner ring (IR monomer) at 3.73 Å resolution by single-particle cryo-electron microscopy, and created an atomic model of the intact IR consisting of 192 molecules of 8 nucleoporins. In each IR monomer, the Z-shaped Nup188–Nup192 complex in the middle layer is sandwiched by two approximately parallel rhomboidal structures in the inner and outer layers, while Nup188, Nup192 and Nic96 link all subunits to constitute a relatively stable IR monomer. In contrast, the intact IR is assembled by loose and instable interactions between IR monomers. These structures, together with previously reported structural information of IR, reveal two distinct interaction modes between IR monomers and extensive flexible connections in IR assembly, providing a structural basis for the stability and malleability of IR.
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Affiliation(s)
- Zongqiang Li
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China.,Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Shuaijiabin Chen
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China.,Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Liang Zhao
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China.,Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Guoqiang Huang
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China.,Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Xiong Pi
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China
| | - Shan Sun
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China
| | - Peiyi Wang
- Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China.,Cryo-EM Center, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Sen-Fang Sui
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China. .,Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong, China. .,Cryo-EM Center, Southern University of Science and Technology, Shenzhen, Guangdong, China.
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9
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Akey CW, Singh D, Ouch C, Echeverria I, Nudelman I, Varberg JM, Yu Z, Fang F, Shi Y, Wang J, Salzberg D, Song K, Xu C, Gumbart JC, Suslov S, Unruh J, Jaspersen SL, Chait BT, Sali A, Fernandez-Martinez J, Ludtke SJ, Villa E, Rout MP. Comprehensive structure and functional adaptations of the yeast nuclear pore complex. Cell 2022; 185:361-378.e25. [PMID: 34982960 PMCID: PMC8928745 DOI: 10.1016/j.cell.2021.12.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 11/26/2021] [Accepted: 12/13/2021] [Indexed: 02/06/2023]
Abstract
Nuclear pore complexes (NPCs) mediate the nucleocytoplasmic transport of macromolecules. Here we provide a structure of the isolated yeast NPC in which the inner ring is resolved by cryo-EM at sub-nanometer resolution to show how flexible connectors tie together different structural and functional layers. These connectors may be targets for phosphorylation and regulated disassembly in cells with an open mitosis. Moreover, some nucleoporin pairs and transport factors have similar interaction motifs, which suggests an evolutionary and mechanistic link between assembly and transport. We provide evidence for three major NPC variants that may foreshadow functional specializations at the nuclear periphery. Cryo-electron tomography extended these studies, providing a model of the in situ NPC with a radially expanded inner ring. Our comprehensive model reveals features of the nuclear basket and central transporter, suggests a role for the lumenal Pom152 ring in restricting dilation, and highlights structural plasticity that may be required for transport.
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Affiliation(s)
- Christopher W Akey
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA.
| | - Digvijay Singh
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Christna Ouch
- Department of Physiology and Biophysics, Boston University School of Medicine, 700 Albany Street, Boston, MA 02118, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Ignacia Echeverria
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, San Francisco, San Francisco, CA 94158, USA
| | - Ilona Nudelman
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
| | | | - Zulin Yu
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Fei Fang
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yi Shi
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Junjie Wang
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Daniel Salzberg
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | - Kangkang Song
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - Chen Xu
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester, MA 01605, USA
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Sergey Suslov
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Jay Unruh
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Sue L Jaspersen
- Stowers Institute for Medical Research, Kansas City, MO, USA; Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Brian T Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA; Quantitative Biosciences Institute, University of California San Francisco, San Francisco, CA 94158, USA; Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94158, USA
| | | | - Steven J Ludtke
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, 1 Baylor Plaza, Houston, Texas 77030, USA.
| | - Elizabeth Villa
- Section of Molecular Biology, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA.
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10
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Nudelman I, Fernandez-Martinez J, Rout MP. Affinity Isolation of Endogenous Saccharomyces Cerevisiae Nuclear Pore Complexes. Methods Mol Biol 2022; 2502:3-34. [PMID: 35412228 PMCID: PMC9200140 DOI: 10.1007/978-1-0716-2337-4_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Studying protein complexes in vitro requires the production of a relatively pure sample that maintains the full complement, native organization, and function of that complex. This can be particularly challenging to achieve for large, multi-component, membrane embedded complexes using the traditional recombinant expression and reconstitution methodologies. However, using affinity capture from native cells, suitable whole endogenous protein complexes can be isolated. Here we present a protocol for the affinity isolation of baker's yeast (S. cerevisiae) nuclear pore complexes, which are ~50 MDa assemblies made up of 552 distinct proteins and embedded in a double-membraned nuclear envelope. Producing this sample allowed us for the first time to perform analyses to characterize the mass, stoichiometry, morphology, and connectivity of this complex and to obtain its integrative structure with ~9 Å precision. We believe this methodology can be applied to other challenging protein complexes to produce similar results.
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Affiliation(s)
- Ilona Nudelman
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
- Fisher Drug Discovery Resource Center (DDRC), The Rockefeller University, New York, NY, USA
| | - Javier Fernandez-Martinez
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, Bizkaia, Spain
| | - Michael P Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, USA.
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11
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Schnell SJ, Tingey M, Yang W. Speed Microscopy: High-Speed Single Molecule Tracking and Mapping of Nucleocytoplasmic Transport. Methods Mol Biol 2022; 2502:353-371. [PMID: 35412250 PMCID: PMC10131132 DOI: 10.1007/978-1-0716-2337-4_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nuclear pore complex (NPC) functions as a gateway through which molecules translocate into and out of the nucleus. Understanding the transport dynamics of these transiting molecules and how they interact with the NPC has great potentials in the discovery of clinical targets. Single-molecule microscopy techniques are powerful tools to provide sub-diffraction limit information about the dynamic and structural details of nucleocytoplasmic transport. Here we detail single-point edge-excitation subdiffraction (SPEED) microscopy, a high-speed superresolution microscopy technique designed to track and map proteins and RNAs as they cross native NPCs.
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Affiliation(s)
| | - Mark Tingey
- Department of Biology, Temple University, Philadelphia, PA, USA
| | - Weidong Yang
- Department of Biology, Temple University, Philadelphia, PA, USA.
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12
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Ptak C, Saik NO, Premashankar A, Lapetina DL, Aitchison JD, Montpetit B, Wozniak RW. Phosphorylation-dependent mitotic SUMOylation drives nuclear envelope-chromatin interactions. J Cell Biol 2021; 220:212843. [PMID: 34787675 PMCID: PMC8641411 DOI: 10.1083/jcb.202103036] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 07/30/2021] [Accepted: 09/22/2021] [Indexed: 12/15/2022] Open
Abstract
In eukaryotes, chromatin binding to the inner nuclear membrane (INM) and nuclear pore complexes (NPCs) contributes to spatial organization of the genome and epigenetic programs important for gene expression. In mitosis, chromatin–nuclear envelope (NE) interactions are lost and then formed again as sister chromosomes segregate to postmitotic nuclei. Investigating these processes in S. cerevisiae, we identified temporally and spatially controlled phosphorylation-dependent SUMOylation events that positively regulate postmetaphase chromatin association with the NE. Our work establishes a phosphorylation-mediated targeting mechanism of the SUMO ligase Siz2 to the INM during mitosis, where Siz2 binds to and SUMOylates the VAP protein Scs2. The recruitment of Siz2 through Scs2 is further responsible for a wave of SUMOylation along the INM that supports the assembly and anchorage of subtelomeric chromatin at the INM and localization of an active gene (INO1) to NPCs during the later stages of mitosis and into G1-phase.
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Affiliation(s)
- Christopher Ptak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Natasha O Saik
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Diego L Lapetina
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | | | - Ben Montpetit
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada.,Department of Viticulture and Enology, University of California Davis, Davis, CA
| | - Richard W Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
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13
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Tang Y, Dong Q, Wang T, Gong L, Gu Y. PNET2 is a component of the plant nuclear lamina and is required for proper genome organization and activity. Dev Cell 2021; 57:19-31.e6. [PMID: 34822788 DOI: 10.1016/j.devcel.2021.11.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/24/2021] [Accepted: 10/29/2021] [Indexed: 01/01/2023]
Abstract
The interaction between chromatin and the nuclear lamina (NL) is intrinsically important to the establishment of three-dimensional chromatin architecture and spatiotemporal regulation of gene expression. However, critical regulators involved in this process are poorly understood in plants. Here, we report that Arabidopsis PNET2 and its two homologs are bona fide inner nuclear membrane proteins and integral components of the NL. PNET2s physically interact with the plant nucleoskeleton and engage nucleosome-enriched chromatin at the nuclear periphery. Loss of all three PNET2s leads to severely disrupted growth and development, concomitant activation of abiotic and biotic stress responses, and ultimate lethality in Arabidopsis. The pent2 triple mutant also displays drastic transcriptome changes accompanied by a globally altered chromatin architecture revealed by HiC analysis. Our study identified PNET2 as an inner nuclear membrane (INM) component of the NL, which associates with chromatin and play a critical role in orchestrating gene expression and chromatin organization in plants.
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Affiliation(s)
- Yu Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA
| | - Qianli Dong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Tianya Wang
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Lei Gong
- Key Laboratory of Molecular Epigenetics of the Ministry of Education (MOE), Northeast Normal University, Changchun 130024, China
| | - Yangnan Gu
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA.
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14
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Mohanta TK, Mishra AK, Al-Harrasi A. The 3D Genome: From Structure to Function. Int J Mol Sci 2021; 22:11585. [PMID: 34769016 PMCID: PMC8584255 DOI: 10.3390/ijms222111585] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/18/2021] [Accepted: 10/20/2021] [Indexed: 01/09/2023] Open
Abstract
The genome is the most functional part of a cell, and genomic contents are organized in a compact three-dimensional (3D) structure. The genome contains millions of nucleotide bases organized in its proper frame. Rapid development in genome sequencing and advanced microscopy techniques have enabled us to understand the 3D spatial organization of the genome. Chromosome capture methods using a ligation approach and the visualization tool of a 3D genome browser have facilitated detailed exploration of the genome. Topologically associated domains (TADs), lamin-associated domains, CCCTC-binding factor domains, cohesin, and chromatin structures are the prominent identified components that encode the 3D structure of the genome. Although TADs are the major contributors to 3D genome organization, they are absent in Arabidopsis. However, a few research groups have reported the presence of TAD-like structures in the plant kingdom.
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Affiliation(s)
- Tapan Kumar Mohanta
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman
| | - Awdhesh Kumar Mishra
- Department of Biotechnology, Yeungnam University, Gyeongsan 38541, Gyeongsangbuk-do, Korea; or
| | - Ahmed Al-Harrasi
- Natural and Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman
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15
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Multifunctionality of F-rich nucleoporins. Biochem Soc Trans 2021; 48:2603-2614. [PMID: 33336681 DOI: 10.1042/bst20200357] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/13/2020] [Accepted: 12/01/2020] [Indexed: 01/11/2023]
Abstract
Nucleoporins (Nups) represent a range of proteins most known for composing the macromolecular assembly of the nuclear pore complex (NPC). Among them, the family of intrinsically disordered proteins (IDPs) phenylalanine-glycine (FG) rich Nups, form the permeability barrier and coordinate the high-speed nucleocytoplasmic transport in a selective way. Those FG-Nups have been demonstrated to participate in various biological processes besides nucleocytoplasmic transport. The high number of accessible hydrophobic motifs of FG-Nups potentially gives rise to this multifunctionality, enabling them to form unique microenvironments. In this review, we discuss the multifunctionality of disordered and F-rich Nups and the diversity of their localizations, emphasizing the important roles of those Nups in various regulatory and metabolic processes.
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16
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Suthakar K, Ryugo DK. Projections from the ventral nucleus of the lateral lemniscus to the cochlea in the mouse. J Comp Neurol 2021; 529:2995-3012. [PMID: 33754334 DOI: 10.1002/cne.25143] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 03/11/2021] [Accepted: 03/12/2021] [Indexed: 02/01/2023]
Abstract
Auditory efferents originate in the central auditory system and project to the cochlea. Although the specific anatomy of the olivocochlear (OC) efferents can vary between species, two types of auditory efferents have been identified based upon the general location of their cell bodies and their distinctly different axon terminations in the organ of Corti. In the mouse, the relatively small somata of the lateral (LOC) efferents reside in the lateral superior olive (LSO), have unmyelinated axons, and terminate around ipsilateral inner hair cells (IHCs), primarily against the afferent processes of type I auditory nerve fibers. In contrast, the larger somata of the medial (MOC) efferents are distributed in the ventral nucleus of the trapezoid body (VNTB), have myelinated axons, and terminate bilaterally against the base of multiple outer hair cells (OHCs). Using in vivo retrograde cell body marking, anterograde axon tracing, immunohistochemistry, and electron microscopy, we have identified a group of efferent neurons in mouse, whose cell bodies reside in the ventral nucleus of the lateral lemniscus (VNLL). By virtue of their location, we call them dorsal efferent (DE) neurons. Labeled DE cells were immuno-negative for tyrosine hydroxylase, glycine, and GABA, but immuno-positive for choline acetyltransferase. Morphologically, DEs resembled LOC efferents by their small somata, unmyelinated axons, and ipsilateral projection to IHCs. These three classes of efferent neurons all project axons directly to the cochlea and exhibit cholinergic staining characteristics. The challenge is to discover the contributions of this new population of neurons to auditory efferent function.
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Affiliation(s)
- Kirupa Suthakar
- Hearing Research, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, UNSW Australia, Sydney, New South Wales, Australia
| | - David K Ryugo
- Hearing Research, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,School of Medical Sciences, Faculty of Medicine, UNSW Australia, Sydney, New South Wales, Australia.,Department of Otolaryngology, Head, Neck & Skull Base Surgery, St. Vincent's Hospital, Sydney, New South Wales, Australia.,The Johns Hopkins University School of Medicine, Otolaryngology-HNS, Baltimore, Maryland, USA
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17
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One Ring to Rule them All? Structural and Functional Diversity in the Nuclear Pore Complex. Trends Biochem Sci 2021; 46:595-607. [PMID: 33563541 DOI: 10.1016/j.tibs.2021.01.003] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/05/2021] [Accepted: 01/11/2021] [Indexed: 02/07/2023]
Abstract
The nuclear pore complex (NPC) is the massive protein assembly that regulates the transport of macromolecules between the nucleus and the cytoplasm. Recent breakthroughs have provided major insights into the structure of the NPC in different eukaryotes, revealing a previously unsuspected diversity of NPC architectures. In parallel, the NPC has been shown to be a key player in regulating essential nuclear processes such as chromatin organization, gene expression, and DNA repair. However, our knowledge of the NPC structure has not been able to address the molecular mechanisms underlying its regulatory roles. We discuss potential explanations, including the coexistence of alternative NPC architectures with specific functional roles.
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18
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Dissecting the Structural Dynamics of the Nuclear Pore Complex. Mol Cell 2020; 81:153-165.e7. [PMID: 33333016 DOI: 10.1016/j.molcel.2020.11.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 10/02/2020] [Accepted: 11/18/2020] [Indexed: 01/03/2023]
Abstract
Cellular processes are largely carried out by macromolecular assemblies, most of which are dynamic, having components that are in constant flux. One such assembly is the nuclear pore complex (NPC), an ∼50 MDa assembly comprised of ∼30 different proteins called Nups that mediates selective macromolecular transport between the nucleus and cytoplasm. We developed a proteomics method to provide a comprehensive picture of the yeast NPC component dynamics. We discovered that, although all Nups display uniformly slow turnover, their exchange rates vary considerably. Surprisingly, this exchange rate was relatively unrelated to each Nup's position, accessibility, or role in transport but correlated with its structural role; scaffold-forming Nups exchange slowly, whereas flexible connector Nups threading throughout the NPC architecture exchange more rapidly. Targeted perturbations in the NPC structure revealed a dynamic resilience to damage. Our approach opens a new window into macromolecular assembly dynamics.
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19
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Genetic circuit design automation for yeast. Nat Microbiol 2020; 5:1349-1360. [DOI: 10.1038/s41564-020-0757-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 06/17/2020] [Indexed: 11/08/2022]
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20
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Zhang Y, Li S, Zeng C, Huang G, Zhu X, Wang Q, Wang K, Zhou Q, Yan C, Zhang W, Yang G, Liu M, Tao Q, Lei J, Shi Y. Molecular architecture of the luminal ring of the Xenopus laevis nuclear pore complex. Cell Res 2020; 30:532-540. [PMID: 32367042 PMCID: PMC7264284 DOI: 10.1038/s41422-020-0320-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 04/06/2020] [Indexed: 12/23/2022] Open
Abstract
The nuclear pore complex (NPC) mediates the flow of substances between the nucleus and cytoplasm in eukaryotic cells. Here we report the cryo-electron tomography (cryo-ET) structure of the luminal ring (LR) of the NPC from Xenopus laevis oocyte. The observed key structural features of the LR are independently confirmed by single-particle cryo-electron microscopy (cryo-EM) analysis. The LR comprises eight butterfly-shaped subunits, each containing two symmetric wings. Each wing consists of four elongated, tubular protomers. Within the LR subunit, the eight protomers form a Finger domain, which directly contacts the fusion between the inner and outer nuclear membranes and a Grid domain, which serves as a rigid base for the Finger domain. Two neighboring LR subunits interact with each other through the lateral edges of their wings to constitute a Bumper domain, which displays two major conformations and appears to cushion neighboring NPCs. Our study reveals previously unknown features of the LR and potentially explains the elastic property of the NPC.
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Affiliation(s)
- Yanqing Zhang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
- Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
| | - Sai Li
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Chao Zeng
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Gaoxingyu Huang
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xuechen Zhu
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
- Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
| | - Qifan Wang
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
- Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
| | - Kunpeng Wang
- Tsinghua Computing Facility & Department of Computer Science, Tsinghua University, Beijing, 100084, China
| | - Qiang Zhou
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
- Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China
| | - Chuangye Yan
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Wusheng Zhang
- Tsinghua Computing Facility & Department of Computer Science, Tsinghua University, Beijing, 100084, China
| | - Guangwen Yang
- Tsinghua Computing Facility & Department of Computer Science, Tsinghua University, Beijing, 100084, China
| | - Minhao Liu
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Qinghua Tao
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jianlin Lei
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yigong Shi
- Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China.
- Institute of Biology, Westlake Institute for Advanced Study, 18 Shilongshan Road, Hangzhou, Zhejiang, 310024, China.
- Beijing Advanced Innovation Center for Structural Biology & Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
- Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, 100084, China.
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21
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Makio T, Wozniak RW. Passive diffusion through nuclear pore complexes regulates levels of the yeast SAGA and SLIK coactivator complexes. J Cell Sci 2020; 133:jcs237156. [PMID: 32051285 DOI: 10.1242/jcs.237156] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 01/31/2020] [Indexed: 11/20/2022] Open
Abstract
Nuclear pore complexes (NPCs) control gene expression by regulating the bi-directional exchange of proteins and RNAs between nuclear and cytoplasmic compartments, including access of transcriptional regulators to the nucleoplasm. Here, we show that the yeast (Saccharomyces cerevisiae) nucleoporin Nup170, in addition to binding and silencing subtelomeric genes, supports transcription of genes regulated by the SAGA transcriptional activator complex. Specifically, we show that a lower amount of SAGA complex is bound to target genes in the absence of Nup170. Consistent with this observation, levels of the SAGA complex are decreased in cells lacking Nup170, while those of the SAGA-related SLIK complexes are increased. This change in the ratio of SAGA to SLIK complexes is due to increased nuclear activity of Pep4, a protease responsible for production of the SLIK complex. Further analyses of various nucleoporin mutants revealed that the increased nuclear entry of Pep4 observed in the nup170Δ mutant likely occurs as the consequence of an increase in the sieving limits of the NPC diffusion channel. On the basis of these results, we propose that changes in passive diffusion rates represent a mechanism for regulating SAGA- and SLIK complex-mediated transcriptional events.
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Affiliation(s)
- Tadashi Makio
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada, T6G 2H7
| | - Richard W Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada, T6G 2H7
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22
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Soheilypour M, Mofrad MRK. Quality control of mRNAs at the entry of the nuclear pore: Cooperation in a complex molecular system. Nucleus 2019; 9:202-211. [PMID: 29431587 PMCID: PMC5973141 DOI: 10.1080/19491034.2018.1439304] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Despite extensive research on how mRNAs are quality controlled prior to export into the cytoplasm, the exact underlying mechanisms are still under debate. Specifically, it is unclear how quality control proteins at the entry of the nuclear pore complex (NPC) distinguish normal and aberrant mRNAs. While some of the involved components are suggested to act as switches and recruit different factors to normal versus aberrant mRNAs, some experimental and computational evidence suggests that the combined effect of the regulated stochastic interactions between the involved components could potentially achieve an efficient quality control of mRNAs. In this review, we present a state-of-the-art portrait of the mRNA quality control research and discuss the current hypotheses proposed for dynamics of the cooperation between the involved components and how it leads to their shared goal: mRNA quality control prior to export into the cytoplasm.
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Affiliation(s)
- Mohammad Soheilypour
- a Molecular Cell Biomechanics Laboratory , Departments of Bioengineering and Mechanical Engineering, University of California , Berkeley
| | - Mohammad R K Mofrad
- a Molecular Cell Biomechanics Laboratory , Departments of Bioengineering and Mechanical Engineering, University of California , Berkeley
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23
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Donnaloja F, Jacchetti E, Soncini M, Raimondi MT. Mechanosensing at the Nuclear Envelope by Nuclear Pore Complex Stretch Activation and Its Effect in Physiology and Pathology. Front Physiol 2019; 10:896. [PMID: 31354529 PMCID: PMC6640030 DOI: 10.3389/fphys.2019.00896] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/27/2019] [Indexed: 02/03/2023] Open
Abstract
Cell fate is correlated to mechanotransduction, in which forces transmitted by the cytoskeleton filaments alter the nuclear shape, affecting transcription factor import/export, cells transcription activity and chromatin distribution. There is in fact evidence that stem cells cultured in 3D environments mimicking the native niche are able to maintain their stemness or modulate their cellular function. However, the molecular and biophysical mechanisms underlying cellular mechanosensing are still largely unclear. The propagation of mechanical stimuli via a direct pathway from cell membrane integrins to SUN proteins residing in the nuclear envelop has been demonstrated, but we suggest that the cells’ fate is mainly affected by the force distribution at the nuclear envelope level, where the SUN protein transmits the stimuli via its mechanical connection to several cell structures such as chromatin, lamina and the nuclear pore complex (NPC). In this review, we analyze the NPC structure and organization, which have not as yet been fully investigated, and its plausible involvement in cell fate. NPC is a multiprotein complex that spans the nuclear envelope, and is involved in several key cellular processes such as bidirectional nucleocytoplasmic exchange, cell cycle regulation, kinetochore organization, and regulation of gene expression. As several connections between the NPC and the nuclear envelope, chromatin and other transmembrane proteins have been identified, it is reasonable to suppose that nuclear deformations can alter the NPC structure. We provide evidence that the transmission of mechanical forces may significantly affects the basket conformation via the Nup153-SUN1 connection, both altering the passage of molecules through it and influencing the state of chromatin packing. Finally, we review the known correlations between a pathological NPC structure and diseases such as cancer, autoimmune disease, aging and laminopathies.
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Affiliation(s)
- F Donnaloja
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
| | - E Jacchetti
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
| | - M Soncini
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, Milan, Italy
| | - M T Raimondi
- Department of Chemistry, Materials and Chemical Engineering "Giulio Natta," Politecnico di Milano, Milan, Italy
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24
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Tessier TM, Dodge MJ, Prusinkiewicz MA, Mymryk JS. Viral Appropriation: Laying Claim to Host Nuclear Transport Machinery. Cells 2019; 8:E559. [PMID: 31181773 PMCID: PMC6627039 DOI: 10.3390/cells8060559] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/05/2019] [Accepted: 06/06/2019] [Indexed: 12/13/2022] Open
Abstract
Protein nuclear transport is an integral process to many cellular pathways and often plays a critical role during viral infection. To overcome the barrier presented by the nuclear membrane and gain access to the nucleus, virally encoded proteins have evolved ways to appropriate components of the nuclear transport machinery. By binding karyopherins, or the nuclear pore complex, viral proteins influence their own transport as well as the transport of key cellular regulatory proteins. This review covers how viral proteins can interact with different components of the nuclear import machinery and how this influences viral replicative cycles. We also highlight the effects that viral perturbation of nuclear transport has on the infected host and how we can exploit viruses as tools to study novel mechanisms of protein nuclear import. Finally, we discuss the possibility that drugs targeting these transport pathways could be repurposed for treating viral infections.
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Affiliation(s)
- Tanner M Tessier
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON N6A 3K7, Canada.
| | - Mackenzie J Dodge
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON N6A 3K7, Canada.
| | - Martin A Prusinkiewicz
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON N6A 3K7, Canada.
| | - Joe S Mymryk
- Department of Microbiology and Immunology, The University of Western Ontario, London, ON N6A 3K7, Canada.
- Department of Otolaryngology, Head & Neck Surgery, The University of Western Ontario, London, ON N6A 3K7, Canada.
- Department of Oncology, The University of Western Ontario, London, ON N6A 3K7, Canada.
- London Regional Cancer Program, Lawson Health Research Institute, London, ON N6A 5W9, Canada.
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25
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Pascual-Garcia P, Capelson M. Nuclear pores in genome architecture and enhancer function. Curr Opin Cell Biol 2019; 58:126-133. [PMID: 31063899 DOI: 10.1016/j.ceb.2019.04.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/28/2019] [Accepted: 04/02/2019] [Indexed: 01/28/2023]
Abstract
Nuclear genome architecture relies on interactions between the genome and various nuclear scaffolds. One such a nuclear scaffold is the nuclear pore complex (NPC), which in addition to its nuclear transport function, can interact with underlying chromatin. In particular, NPCs have been recently reported to associate with a number of enhancers and superenhancers in metazoan genomes, and select NPC components have been shown to promote the formation of specific genomic loops. Here, we provide a brief overview of current models of enhancer function, and discuss recent evidence that NPCs bind enhancers and contribute to topological genome organization. We also examine possible models of how gene and enhancer targeting to NPCs may contribute to tissue-specific genome architecture and expression programs, including the possibility that NPCs may promote phase separation of transcriptional compartments.
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Affiliation(s)
- Pau Pascual-Garcia
- Department of Cell and Developmental Biology, Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Maya Capelson
- Department of Cell and Developmental Biology, Penn Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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26
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Mullan PB, Bingham V, Haddock P, Irwin GW, Kay E, McQuaid S, Buckley NE. NUP98 - a novel predictor of response to anthracycline-based chemotherapy in triple negative breast cancer. BMC Cancer 2019; 19:236. [PMID: 30935371 PMCID: PMC6444590 DOI: 10.1186/s12885-019-5407-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/25/2019] [Indexed: 12/31/2022] Open
Abstract
Background Triple Negative breast cancer (TNBC) is a poor outcome subgroup of breast cancer defined based on the absence of expression of ERα and PR and HER2 amplification. These hard to treat cancers lack targeted treatment options and are therefore treated with a standard of care (SoC) generic cocktail of DNA damaging chemotherapy, with a wide range of clinical responses. While a subset of TNBC patients respond very well to this treatment, others receive no clinical benefit and die from their disease within a short time period. We currently lack biomarkers to prospectively identify patients likely to relapse and we lack alternate treatment options. Methods NUP98 protein expression was investigated in patient samples using two independent tissue microarrays (TMAs), as well as a normal breast TMA. Correlation with pathological response to various chemotherapy regimens was investigated. Results We have shown that high NUP98 is significantly associated with poor outcome in TNBC patient samples both by gene expression and IHC-based protein analysis. While trends linking NUP98 expression with poorer outcomes were observed in breast cancer overall (and more specifically in the LuminalB Her2- subgroup), significant correlations were observed in TNBC. This appeared to be specific to anthracycline based regimens as the association between NUP98 and response was not observed in patients treated with taxane-based chemotherapy. Conclusions We have identified a novel biomarker, NUP98, that can predict response to anthracycline based chemotherapy in TNBC. The ability to prospectively identify patients who are less likely to respond to SoC chemotherapy is a vital step in improving the overall survival of these patients. Electronic supplementary material The online version of this article (10.1186/s12885-019-5407-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paul B Mullan
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, BT9 7AE, Northern Ireland
| | - Victoria Bingham
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, BT9 7AE, Northern Ireland
| | - Paula Haddock
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, Northern Ireland
| | - Gareth W Irwin
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, BT9 7AE, Northern Ireland.,Nightingale Breast Centre, Wythenshawe Hospital, Manchester University Foundation Trust, Manchester, UK
| | - Elaine Kay
- Department of Surgery, Beaumont Hospital and Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Stephen McQuaid
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, BT9 7AE, Northern Ireland
| | - Niamh E Buckley
- School of Pharmacy, Queen's University Belfast, Belfast, BT9 7BL, Northern Ireland.
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27
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Champion L, Pawar S, Luithle N, Ungricht R, Kutay U. Dissociation of membrane-chromatin contacts is required for proper chromosome segregation in mitosis. Mol Biol Cell 2018; 30:427-440. [PMID: 30586323 PMCID: PMC6594442 DOI: 10.1091/mbc.e18-10-0609] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The nuclear envelope (NE) aids in organizing the interphase genome by tethering chromatin to the nuclear periphery. During mitotic entry, NE–chromatin contacts are broken. Here, we report on the consequences of impaired NE removal from chromatin for cell division of human cells. Using a membrane–chromatin tether that cannot be dissociated when cells enter mitosis, we show that a failure in breaking membrane–chromatin interactions impairs mitotic chromatin organization, chromosome segregation and cytokinesis, and induces an aberrant NE morphology in postmitotic cells. In contrast, chromosome segregation and cell division proceed successfully when membrane attachment to chromatin is induced during metaphase, after chromosomes have been singularized and aligned at the metaphase plate. These results indicate that the separation of membranes and chromatin is critical during prometaphase to allow for proper chromosome compaction and segregation. We propose that one cause of these defects is the multivalency of membrane–chromatin interactions.
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Affiliation(s)
- Lysie Champion
- Department of Biology, Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Sumit Pawar
- Department of Biology, Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Naemi Luithle
- Department of Biology, Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Rosemarie Ungricht
- Department of Biology, Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Ulrike Kutay
- Department of Biology, Institute of Biochemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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28
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Lebedeva LA, Yakovlev KV, Kozlov EN, Schedl P, Deshpande G, Shidlovskii YV. Transcriptional quiescence in primordial germ cells. Crit Rev Biochem Mol Biol 2018; 53:579-595. [PMID: 30280955 PMCID: PMC8729227 DOI: 10.1080/10409238.2018.1506733] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/09/2018] [Accepted: 07/27/2018] [Indexed: 12/31/2022]
Abstract
In most animal species, newly formed primordial germ cells (PGCs) acquire the special characteristics that distinguish them from the surrounding somatic cells. Proper fate specification of the PGCs is coupled with transcriptional quiescence, whether they are segregated by determinative or inductive mechanisms. Inappropriate differentiation of PGCs into somatic cells is thought to be prevented due to repression of RNA polymerase (Pol) II-dependent transcription. In the case of a determinative mode of PGC formation (Drosophila, Caenorhabditis elegans, etc.), there is a broad downregulation of Pol II activity. By contrast, PGCs display only gene-specific repression in organisms that rely on inductive signaling-based mechanism (e.g., mice). In addition to the global block of Pol II activity in PGCs, gene expression can be suppressed in other ways, such as chromatin remodeling and Piwi-mediated RNAi. Here, we discuss the mechanisms responsible for the transcriptionally silent state of PGCs in common experimental animals, such as Drosophila, C. elegans, Danio rerio, Xenopus, and mouse. While a PGC-specific downregulation of transcription is a common feature among these organisms, the diverse nature of underlying mechanisms suggests that this functional trait likely evolved independently on several instances. We discuss the possible biological relevance of these silencing mechanisms vis-a-vis fate determination of PGCs.
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Affiliation(s)
| | - Konstantin V. Yakovlev
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Laboratory of Cytotechnology, National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
| | - Eugene N. Kozlov
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Paul Schedl
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Department of Molecular Biology, Princeton University, Princeton, USA
| | - Girish Deshpande
- Department of Molecular Biology, Princeton University, Princeton, USA
| | - Yulii V. Shidlovskii
- Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, Moscow, Russia
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29
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de Bruyn Kops A, Burke JE, Guthrie C. Brr6 plays a role in gene recruitment and transcriptional regulation at the nuclear envelope. Mol Biol Cell 2018; 29:2578-2590. [PMID: 30133335 PMCID: PMC6254580 DOI: 10.1091/mbc.e18-04-0258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Correlation between transcriptional regulation and positioning of genes at the nuclear envelope is well established in eukaryotes, but the mechanisms involved are not well understood. We show that brr6-1, a mutant of the essential yeast envelope transmembrane protein Brr6p, impairs normal positioning and expression of the PAB1 and FUR4-GAL1,10,7 loci. Similarly, expression of a dominant negative nucleoplasmic Brr6 fragment in wild-type cells reproduced many of the brr6-1 effects. Histone chromatin immunoprecipitation (ChIP) experiments showed decreased acetylation at the key histone H4K16 residue in the FUR4-GAL1,10,7 region in brr6-1. Importantly, blocking deacetylation significantly suppressed selected brr6-1 phenotypes. ChIPseq with FLAG-tagged Brr6 fragments showed enrichment at FUR4 and several other genes that showed striking changes in brr6-1 RNAseq data. These associations depended on a Brr6 putative zinc finger domain. Importantly, artificially tethering the GAL1 locus to the envelope suppressed the brr6-1 effects on GAL1 and FUR4 expression and increased H4K16 acetylation between GAL1 and FUR4 in the mutant. Together these results argue that Brr6 interacts with chromatin, helping to maintain normal chromatin architecture and transcriptional regulation of certain loci at the nuclear envelope.
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Affiliation(s)
- Anne de Bruyn Kops
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| | - Jordan E Burke
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
| | - Christine Guthrie
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143
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30
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Manhas S, Ma L, Measday V. The yeast Ty1 retrotransposon requires components of the nuclear pore complex for transcription and genomic integration. Nucleic Acids Res 2018; 46:3552-3578. [PMID: 29514267 PMCID: PMC5909446 DOI: 10.1093/nar/gky109] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 02/01/2018] [Accepted: 02/26/2018] [Indexed: 01/06/2023] Open
Abstract
Nuclear pore complexes (NPCs) orchestrate cargo between the cytoplasm and nucleus and regulate chromatin organization. NPC proteins, or nucleoporins (Nups), are required for human immunodeficiency virus type 1 (HIV-1) gene expression and genomic integration of viral DNA. We utilize the Ty1 retrotransposon of Saccharomyces cerevisiae (S. cerevisiae) to study retroviral integration because retrotransposons are the progenitors of retroviruses and have conserved integrase (IN) enzymes. Ty1-IN targets Ty1 elements into the genome upstream of RNA polymerase (Pol) III transcribed genes such as transfer RNA (tRNA) genes. Evidence that S. cerevisiae tRNA genes are recruited to NPCs prompted our investigation of a functional role for the NPC in Ty1 targeting into the genome. We find that Ty1 mobility is reduced in multiple Nup mutants that cannot be accounted for by defects in Ty1 gene expression, cDNA production or Ty1-IN nuclear entry. Instead, we find that Ty1 insertion upstream of tRNA genes is impaired. We also identify Nup mutants with wild type Ty1 mobility but impaired Ty1 targeting. The NPC nuclear basket, which interacts with chromatin, is required for both Ty1 expression and nucleosome targeting. Deletion of components of the NPC nuclear basket causes mis-targeting of Ty1 elements to the ends of chromosomes.
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Affiliation(s)
- Savrina Manhas
- Department of Biochemistry and Molecular Biology, 2350 Health Sciences Mall, Life Sciences Centre, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Lina Ma
- Wine Research Centre, 2205 East Mall, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
| | - Vivien Measday
- Department of Biochemistry and Molecular Biology, 2350 Health Sciences Mall, Life Sciences Centre, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
- Wine Research Centre, 2205 East Mall, Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
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31
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Abstract
Despite the central role of Nuclear Pore Complexes (NPCs) as gatekeepers of RNA and protein transport between the cytoplasm and nucleoplasm, their large size and dynamic nature have impeded a full structural and functional elucidation. Here, we have determined a subnanometer precision structure for the entire 552-protein yeast NPC by satisfying diverse data including stoichiometry, a cryo-electron tomography map, and chemical cross-links. The structure reveals the NPC’s functional elements in unprecedented detail. The NPC is built of sturdy diagonal columns to which are attached connector cables, imbuing both strength and flexibility, while tying together all other elements of the NPC, including membrane-interacting regions and RNA processing platforms. Inwardly-directed anchors create a high density of transport factor-docking Phe-Gly repeats in the central channel, organized in distinct functional units. Taken together, this integrative structure allows us to rationalize the architecture, transport mechanism, and evolutionary origins of the NPC.
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32
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Sump B, Brickner JH. Nup98 regulation of histone methylation promotes normal gene expression and may drive leukemogenesis. Genes Dev 2018; 31:2201-2203. [PMID: 29284709 PMCID: PMC5769765 DOI: 10.1101/gad.310359.117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This Outlook by Sump and Brickner highlights the work of Franks et al., which provides new mechanistic insight into the molecular basis by which Nup98 promotes gene activation in normal hematopoietic cells and how that process is altered by translocations to cause excess expression of developmental genes in leukemia. Nuclear pore proteins (Nups) interact with chromosomes to regulate gene expression and chromatin structure. A new study by Franks and colleagues (pp. 2222–2234) provides new mechanistic insight into the molecular basis by which Nup98 promotes gene activation in normal hematopoietic cells and how that process is altered by translocations to cause excess expression of developmental genes in leukemia.
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Affiliation(s)
- Bethany Sump
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, USA
| | - Jason H Brickner
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois 60208, USA
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33
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Haskell GT, Jensen BC, Samsa LA, Marchuk D, Huang W, Skrzynia C, Tilley C, Seifert BA, Rivera-Muñoz EA, Koller B, Wilhelmsen KC, Liu J, Alhosaini H, Weck KE, Evans JP, Berg JS. Whole Exome Sequencing Identifies Truncating Variants in Nuclear Envelope Genes in Patients With Cardiovascular Disease. ACTA ACUST UNITED AC 2018; 10:CIRCGENETICS.116.001443. [PMID: 28611029 DOI: 10.1161/circgenetics.116.001443] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 03/20/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND The genetic variation underlying many heritable forms of cardiovascular disease is incompletely understood, even in patients with strong family history or early age at onset. METHODS AND RESULTS We used whole exome sequencing to detect pathogenic variants in 55 patients with suspected monogenic forms of cardiovascular disease. Diagnostic analysis of established disease genes identified pathogenic variants in 21.8% of cases and variants of uncertain significance in 34.5% of cases. Three patients harbored heterozygous nonsense or splice-site variants in the nucleoporin genes NUP37, NUP43, and NUP188, which have not been implicated previously in cardiac disease. We also identified a heterozygous splice site variant in the nuclear envelope gene SYNE1 in a child with severe dilated cardiomyopathy that underwent transplant, as well as in his affected father. To confirm a cardiovascular role for these candidate genes in vivo, we used morpholinos to reduce SYNE1, NUP37, and NUP43 gene expression in zebrafish. Morphant embryos displayed cardiac abnormalities, including pericardial edema and heart failure. Furthermore, lymphoblasts from the patient carrying a SYNE1 splice-site variant displayed changes in nuclear morphology and protein localization that are consistent with disruption of the nuclear envelope. CONCLUSIONS These data expand the repertoire of pathogenic variants associated with cardiovascular disease and validate the diagnostic and research use of whole exome sequencing. We identify NUP37, NUP43, and NUP188 as novel candidate genes for cardiovascular disease, and suggest that dysfunction of the nuclear envelope may be an under-recognized component of inherited cardiac disease in some cases.
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Affiliation(s)
- Gloria T Haskell
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.).
| | - Brian C Jensen
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Leigh Ann Samsa
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Daniel Marchuk
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Wei Huang
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Cecile Skrzynia
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Christian Tilley
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Bryce A Seifert
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Edgar A Rivera-Muñoz
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Beverly Koller
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Kirk C Wilhelmsen
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Jiandong Liu
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Hassan Alhosaini
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Karen E Weck
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - James P Evans
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
| | - Jonathan S Berg
- From the Department of Pathology, Duke University, Durham, NC (G.T.H.); Division of Cardiology (B.C.J.), McAllister Heart Institute (B.C.J., L.A.S., W.H., J.L.), Department of Cell and Molecular Physiology (L.A.S., W.H., J.L.), Department of Genetics (D.M., C.S., C.T., B.A.S., E.A.R.-M., B.K., K.C.W., K.E.W., J.P.E., J.S.B.), Department of Pathology and Laboratory Medicine (J.L., K.E.W.), UNC School of Medicine, Chapel Hill; Renaissance Computing Institute, Chapel Hill, NC (K.C.W.); and ECU Heart Institute, Brody School of Medicine, Greenville, NC (H.A.)
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Ne E, Palstra RJ, Mahmoudi T. Transcription: Insights From the HIV-1 Promoter. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 335:191-243. [DOI: 10.1016/bs.ircmb.2017.07.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Franks TM, McCloskey A, Shokirev MN, Benner C, Rathore A, Hetzer MW. Nup98 recruits the Wdr82-Set1A/COMPASS complex to promoters to regulate H3K4 trimethylation in hematopoietic progenitor cells. Genes Dev 2017; 31:2222-2234. [PMID: 29269482 PMCID: PMC5769767 DOI: 10.1101/gad.306753.117] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/21/2017] [Indexed: 12/26/2022]
Abstract
In this study, Franks et al. investigated the mechanisms underlying how Nup98 regulates gene expression. They show that in hematopoietic cells, Nup98 binds predominantly to transcription start sites to recruit the Wdr82–Set1A/COMPASS complex, which is required for deposition of the histone 3 Lys4 trimethyl (H3K4me3)-activating mark, and expression of a Nup98 fusion protein implicated in aggressive AML causes mislocalization of H3K4me3 at aberrant regions and up-regulation of associated genes due to aberrant Wdr82/Set1A activity. Recent studies have shown that a subset of nucleoporins (Nups) can detach from the nuclear pore complex and move into the nuclear interior to regulate transcription. One such dynamic Nup, called Nup98, has been implicated in gene activation in healthy cells and has been shown to drive leukemogenesis when mutated in patients with acute myeloid leukemia (AML). Here we show that in hematopoietic cells, Nup98 binds predominantly to transcription start sites to recruit the Wdr82–Set1A/COMPASS (complex of proteins associated with Set1) complex, which is required for deposition of the histone 3 Lys4 trimethyl (H3K4me3)-activating mark. Depletion of Nup98 or Wdr82 abolishes Set1A recruitment to chromatin and subsequently ablates H3K4me3 at adjacent promoters. Furthermore, expression of a Nup98 fusion protein implicated in aggressive AML causes mislocalization of H3K4me3 at abnormal regions and up-regulation of associated genes. Our findings establish a function of Nup98 in hematopoietic gene activation and provide mechanistic insight into which Nup98 leukemic fusion proteins promote AML.
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Affiliation(s)
- Tobias M Franks
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Asako McCloskey
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Maxim Nikolaievich Shokirev
- The Razavi Newman Integrative Genomics and Bioinformatics Core, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Chris Benner
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA.,Department of Medicine, University of California at San Diego, La Jolla, California 92093, USA
| | - Annie Rathore
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Martin W Hetzer
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
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Rai SK, Sangesland M, Lee M, Esnault C, Cui Y, Chatterjee AG, Levin HL. Host factors that promote retrotransposon integration are similar in distantly related eukaryotes. PLoS Genet 2017; 13:e1006775. [PMID: 29232693 PMCID: PMC5741268 DOI: 10.1371/journal.pgen.1006775] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 12/22/2017] [Accepted: 11/07/2017] [Indexed: 12/14/2022] Open
Abstract
Retroviruses and Long Terminal Repeat (LTR)-retrotransposons have distinct patterns of integration sites. The oncogenic potential of retrovirus-based vectors used in gene therapy is dependent on the selection of integration sites associated with promoters. The LTR-retrotransposon Tf1 of Schizosaccharomyces pombe is studied as a model for oncogenic retroviruses because it integrates into the promoters of stress response genes. Although integrases (INs) encoded by retroviruses and LTR-retrotransposons are responsible for catalyzing the insertion of cDNA into the host genome, it is thought that distinct host factors are required for the efficiency and specificity of integration. We tested this hypothesis with a genome-wide screen of host factors that promote Tf1 integration. By combining an assay for transposition with a genetic assay that measures cDNA recombination we could identify factors that contribute differentially to integration. We utilized this assay to test a collection of 3,004 S. pombe strains with single gene deletions. Using these screens and immunoblot measures of Tf1 proteins, we identified a total of 61 genes that promote integration. The candidate integration factors participate in a range of processes including nuclear transport, transcription, mRNA processing, vesicle transport, chromatin structure and DNA repair. Two candidates, Rhp18 and the NineTeen complex were tested in two-hybrid assays and were found to interact with Tf1 IN. Surprisingly, a number of pathways we identified were found previously to promote integration of the LTR-retrotransposons Ty1 and Ty3 in Saccharomyces cerevisiae, indicating the contribution of host factors to integration are common in distantly related organisms. The DNA repair factors are of particular interest because they may identify the pathways that repair the single stranded gaps flanking the sites of strand transfer following integration of LTR retroelements. Retroviruses and retrotransposons are genetic elements that propagate by integrating into chromosomes of eukaryotic cells. Genetic disorders are being treated with retrovirus-based vectors that integrate corrective genes into the chromosomes of patients. Unfortunately, the vectors can alter expression of adjacent genes and depending on the position of integration, cancer genes can be induced. It is therefore essential that we understand how integration sites are selected. Interestingly, different retroviruses and retrotransposons have different profiles of integration sites. While specific proteins have been identified that select target sites, it’s not known what other cellular factors promote integration. In this paper, we report a comprehensive screen of host factors that promote LTR-retrotransposon integration in the widely-studied yeast, Schizosaccharomyces pombe. Unexpectedly, we found a wide range of pathways and host factors participate in integration. And importantly, we found the cellular processes that promote integration relative to recombination in S. pombe are the same that drive integration of LTR-retrotransposons in the distantly related yeast Saccharomyces cerevisiae. This suggests a specific set of cellular pathways are responsible for integration in a wide range of eukaryotic hosts.
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Affiliation(s)
- Sudhir Kumar Rai
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Maya Sangesland
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Michael Lee
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Caroline Esnault
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Yujin Cui
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Atreyi Ghatak Chatterjee
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Henry L. Levin
- Section on Eukaryotic Transposable Elements, Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health (NIH), Bethesda, Maryland, United States of America
- * E-mail:
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Capitanio JS, Montpetit B, Wozniak RW. Nucleoplasmic Nup98 controls gene expression by regulating a DExH/D-box protein. Nucleus 2017; 9:1-8. [PMID: 28934014 PMCID: PMC5973140 DOI: 10.1080/19491034.2017.1364826] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The nucleoporin Nup98 has been linked to the regulation of transcription and RNA metabolism, 1-3 but the mechanisms by which Nup98 contributes to these processes remains largely undefined. Recently, we uncovered interactions between Nup98 and several DExH/D-box proteins (DBPs), a protein family well-known for modulating gene expression and RNA metabolism. 4-6 Analysis of Nup98 and one of these DBPs, DHX9, showed that they directly interact, their association is facilitated by RNA, and Nup98 binding stimulates DHX9 ATPase activity. 7 Furthermore, these proteins were dependent on one another for their proper association with a subset of gene loci to control transcription and modulate mRNA splicing. 7 On the basis of these observations, we proposed that Nup98 functions to regulate DHX9 activity within the nucleoplasm. 7 Since Nup98 is associated with several DBPs, regulation of DHX9 by Nup98 may represent a paradigm for understanding how Nup98, and possibly other FG-Nup proteins, could direct the diverse cellular activities of multiple DBPs.
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Affiliation(s)
| | - Ben Montpetit
- a Department of Cell Biology , University of Alberta , Edmonton , Canada.,b Department of Viticulture and Enology , University of California at Davis , Davis , CA , USA
| | - Richard W Wozniak
- a Department of Cell Biology , University of Alberta , Edmonton , Canada
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Lapetina DL, Ptak C, Roesner UK, Wozniak RW. Yeast silencing factor Sir4 and a subset of nucleoporins form a complex distinct from nuclear pore complexes. J Cell Biol 2017; 216:3145-3159. [PMID: 28883038 PMCID: PMC5626528 DOI: 10.1083/jcb.201609049] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 05/26/2017] [Accepted: 07/31/2017] [Indexed: 11/22/2022] Open
Abstract
Lapetina et al. identify a protein interaction network involved in the association of chromatin with the nuclear envelope. This network includes a telomere tether, a silencing factor, a SUMO E3 ligase, and an array of nucleoporins that together form a complex distinct from nuclear pore complexes. Interactions occurring at the nuclear envelope (NE)–chromatin interface influence both NE structure and chromatin organization. Insights into the functions of NE–chromatin interactions have come from the study of yeast subtelomeric chromatin and its association with the NE, including the identification of various proteins necessary for tethering subtelomeric chromatin to the NE and the silencing of resident genes. Here we show that four of these proteins—the silencing factor Sir4, NE-associated Esc1, the SUMO E3 ligase Siz2, and the nuclear pore complex (NPC) protein Nup170—physically and functionally interact with one another and a subset of NPC components (nucleoporins or Nups). Importantly, this group of Nups is largely restricted to members of the inner and outer NPC rings, but it lacks numerous others including cytoplasmically and nucleoplasmically positioned Nups. We propose that this Sir4-associated Nup complex is distinct from holo-NPCs and that it plays a role in subtelomeric chromatin organization and NE tethering.
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Affiliation(s)
- Diego L Lapetina
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Christopher Ptak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Ulyss K Roesner
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
| | - Richard W Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada
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Obado SO, Field MC, Rout MP. Comparative interactomics provides evidence for functional specialization of the nuclear pore complex. Nucleus 2017; 8:340-352. [PMID: 28463551 DOI: 10.1080/19491034.2017.1313936] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
The core architecture of the eukaryotic cell was established well over one billion years ago, and is largely retained in all extant lineages. However, eukaryotic cells also possess lineage-specific features, frequently keyed to specific functional requirements. One quintessential core eukaryotic structure is the nuclear pore complex (NPC), responsible for regulating exchange of macromolecules between the nucleus and cytoplasm as well as acting as a nuclear organizational hub. NPC architecture has been best documented in one eukaryotic supergroup, the Opisthokonts (e.g. Saccharomyces cerevisiae and Homo sapiens), which although compositionally similar, have significant variations in certain NPC subcomplex structures. The variation of NPC structure across other taxa in the eukaryotic kingdom however, remains poorly understood. We explored trypanosomes, highly divergent organisms, and mapped and assigned their NPC proteins to specific substructures to reveal their NPC architecture. We showed that the NPC central structural scaffold is conserved, likely across all eukaryotes, but more peripheral elements can exhibit very significant lineage-specific losses, duplications or other alterations in their components. Amazingly, trypanosomes lack the major components of the mRNA export platform that are asymmetrically localized within yeast and vertebrate NPCs. Concomitant with this, the trypanosome NPC is ALMOST completely symmetric with the nuclear basket being the only major source of asymmetry. We suggest these features point toward a stepwise evolution of the NPC in which a coating scaffold first stabilized the pore after which selective gating emerged and expanded, leading to the addition of peripheral remodeling machineries on the nucleoplasmic and cytoplasmic sides of the pore.
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Affiliation(s)
| | - Mark C Field
- b Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences , University of Dundee , Dundee , UK
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Capitanio JS, Montpetit B, Wozniak RW. Human Nup98 regulates the localization and activity of DExH/D-box helicase DHX9. eLife 2017; 6. [PMID: 28221134 PMCID: PMC5338925 DOI: 10.7554/elife.18825] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 02/16/2017] [Indexed: 12/17/2022] Open
Abstract
Beyond their role at nuclear pore complexes, some nucleoporins function in the nucleoplasm. One such nucleoporin, Nup98, binds chromatin and regulates gene expression. To gain insight into how Nup98 contributes to this process, we focused on identifying novel binding partners and understanding the significance of these interactions. Here we report on the identification of the DExH/D-box helicase DHX9 as an intranuclear Nup98 binding partner. Various results, including in vitro assays, show that the FG/GLFG region of Nup98 binds to N- and C-terminal regions of DHX9 in an RNA facilitated manner. Importantly, binding of Nup98 stimulates the ATPase activity of DHX9, and a transcriptional reporter assay suggests Nup98 supports DHX9-stimulated transcription. Consistent with these observations, our analysis revealed that Nup98 and DHX9 bind interdependently to similar gene loci and their transcripts. Based on our results, we propose that Nup98 functions as a co-factor that regulates DHX9 and, potentially, other RNA helicases.
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Affiliation(s)
| | - Ben Montpetit
- Department of Cell Biology, University of Alberta, Edmonton, Canada.,Department of Viticulture and Enology, University of California, Davis, United states
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41
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The benefits of integration. Clin Microbiol Infect 2017; 22:324-332. [PMID: 27107301 DOI: 10.1016/j.cmi.2016.02.013] [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] [Received: 02/21/2016] [Revised: 02/21/2016] [Accepted: 02/21/2016] [Indexed: 01/06/2023]
Abstract
Retroviruses, including the human immunodeficiency virus (HIV), are notorious for two essential steps of their viral replication: reverse transcription and integration. This latter property is considered to be essential for productive replication and ensures the stable long-term insertion of the viral genome sequence in the host chromatin, thereby leading to the life-long association of the virus with the infected cell. Using HIV as a prototypic example, the present review aims to provide an overview of how and where integration occurs, as well as presenting general consequences for both the virus and the infected host.
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42
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Beck M, Hurt E. The nuclear pore complex: understanding its function through structural insight. Nat Rev Mol Cell Biol 2016; 18:73-89. [PMID: 27999437 DOI: 10.1038/nrm.2016.147] [Citation(s) in RCA: 423] [Impact Index Per Article: 52.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nuclear pore complexes (NPCs) fuse the inner and outer nuclear membranes to form channels across the nuclear envelope. They are large macromolecular assemblies with a complex composition and diverse functions. Apart from facilitating nucleocytoplasmic transport, NPCs are involved in chromatin organization, the regulation of gene expression and DNA repair. Understanding the molecular mechanisms underlying these functions has been hampered by a lack of structural knowledge about the NPC. The recent convergence of crystallographic and biochemical in vitro analysis of nucleoporins (NUPs), the components of the NPC, with cryo-electron microscopic imaging of the entire NPC in situ has provided first pseudo-atomic view of its central core and revealed that an unexpected network of short linear motifs is an important spatial organization principle. These breakthroughs have transformed the way we understand NPC structure, and they provide an important base for functional investigations, including the elucidation of the molecular mechanisms underlying clinically manifested mutations of the nucleocytoplasmic transport system.
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Affiliation(s)
- Martin Beck
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstrasse 1, Heidelberg D-69117, Germany
| | - Ed Hurt
- Biochemistry Center of Heidelberg University, INF328, Heidelberg D-69120, Germany
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Sarkar A, Pech M, Thoms M, Beckmann R, Hurt E. Ribosome-stalk biogenesis is coupled with recruitment of nuclear-export factor to the nascent 60S subunit. Nat Struct Mol Biol 2016; 23:1074-1082. [PMID: 27775710 DOI: 10.1038/nsmb.3312] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 09/26/2016] [Indexed: 12/16/2022]
Abstract
Nuclear export of preribosomal subunits is a key step during eukaryotic ribosome formation. To efficiently pass through the FG-repeat meshwork of the nuclear pore complex, the large pre-60S subunit requires several export factors. Here we describe the mechanism of recruitment of the Saccharomyces cerevisiae RNA-export receptor Mex67-Mtr2 to the pre-60S subunit at the proper time. Mex67-Mtr2 binds at the premature ribosomal-stalk region, which later during translation serves as a binding platform for translational GTPases on the mature ribosome. The assembly factor Mrt4, a structural homolog of cytoplasmic-stalk protein P0, masks this site, thus preventing untimely recruitment of Mex67-Mtr2 to nuclear pre-60S particles. Subsequently, Yvh1 triggers Mrt4 release in the nucleus, thereby creating a narrow time window for Mex67-Mtr2 association at this site and facilitating nuclear export of the large subunit. Thus, a spatiotemporal mark on the ribosomal stalk controls the recruitment of an RNA-export receptor to the nascent 60S subunit.
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Affiliation(s)
- Anshuk Sarkar
- Biochemistry Centre, University of Heidelberg, Heidelberg, Germany
| | - Markus Pech
- Gene Center, University of Munich, Munich, Germany
| | - Matthias Thoms
- Biochemistry Centre, University of Heidelberg, Heidelberg, Germany
| | | | - Ed Hurt
- Biochemistry Centre, University of Heidelberg, Heidelberg, Germany
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44
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Saad H, Cobb JA. A decade of understanding spatio-temporal regulation of DNA repair by the nuclear architecture. Biochem Cell Biol 2016; 94:433-440. [DOI: 10.1139/bcb-2016-0085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The nucleus is a hub for gene expression and is a highly organized entity. The nucleoplasm is heterogeneous, owing to the preferential localization of specific metabolic factors, which lead to the definition of nuclear compartments or bodies. The genome is organized into chromosome territories, as well as heterochromatin and euchromatin domains. Recent observations have indicated that nuclear organization is important for maintaining genomic stability. For example, nuclear organization has been implicated in stabilizing damaged DNA, repair-pathway choice, and in preventing chromosomal rearrangements. Over the past decade, several studies have revealed that dynamic changes in the nuclear architecture are important during double-strand break repair. Stemming from work in yeast, relocation of a damaged site prior to repair appears to be at least partially conserved in multicellular eukaryotes. In this review, we will discuss genome and nucleoplasm architecture, particularly the importance of the nuclear periphery in genome stability. We will also discuss how the site of relocation regulates repair-pathway choice.
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Affiliation(s)
- Hicham Saad
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
| | - Jennifer A. Cobb
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
- Southern Alberta Cancer Research Institute, Departments of Biochemistry & Molecular Biology and Oncology, Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Cumming School of Medicine; University of Calgary; 3330 Hospital Drive N.W., Calgary, AB T2N 4N1, Canada
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45
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Niño CA, Guet D, Gay A, Brutus S, Jourquin F, Mendiratta S, Salamero J, Géli V, Dargemont C. Posttranslational marks control architectural and functional plasticity of the nuclear pore complex basket. J Cell Biol 2016; 212:167-80. [PMID: 26783300 PMCID: PMC4738382 DOI: 10.1083/jcb.201506130] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ubiquitin modifications of the nuclear pore complex (NPC) control the architectural plasticity of the nuclear basket, contributing to its tethering to the core NPC, with consequences on the cellular response to DNA damage and telomere recombination. The nuclear pore complex (NPC) serves as both the unique gate between the nucleus and the cytoplasm and a major platform that coordinates nucleocytoplasmic exchanges, gene expression, and genome integrity. To understand how the NPC integrates these functional constraints, we dissected here the posttranslational modifications of the nuclear basket protein Nup60 and analyzed how they intervene to control the plasticity of the NPC. Combined approaches highlight the role of monoubiquitylation in regulating the association dynamics of Nup60 and its partner, Nup2, with the NPC through an interaction with Nup84, a component of the Y complex. Although major nuclear transport routes are not regulated by Nup60 modifications, monoubiquitylation of Nup60 is stimulated upon genotoxic stress and regulates the DNA-damage response and telomere repair. Together, these data reveal an original mechanism contributing to the plasticity of the NPC at a molecular-organization and functional level.
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Affiliation(s)
- Carlos A Niño
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
| | - David Guet
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
| | - Alexandre Gay
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
| | - Sergine Brutus
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
| | - Frédéric Jourquin
- Aix-Marseille University, CNRS UMR 7258, INSERM UMR1068, Institut Paoli-Calmettes, Cancer Research Center of Marseille, Equipe labellisée Ligue contre le cancer, 13273 Marseille, France
| | - Shweta Mendiratta
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
| | - Jean Salamero
- Institut Curie, PSL Research University, CNRS UMR 144, Pierre-and-Marie-Curie Université, Team-Space time imaging of endomembranes and organelles dynamics and PICT-IBiSA Imaging Core Facility, 75005 Paris, France
| | - Vincent Géli
- Aix-Marseille University, CNRS UMR 7258, INSERM UMR1068, Institut Paoli-Calmettes, Cancer Research Center of Marseille, Equipe labellisée Ligue contre le cancer, 13273 Marseille, France
| | - Catherine Dargemont
- University Paris Diderot, Sorbonne Paris Cité, Pathologie et Virologie Moléculaire, Institut National de la Santé et de la Recherche Medicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Equipe labellisée Ligue contre le cancer, Hôpital St. Louis, 75475 Paris, France
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46
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Abstract
Nuclear pore complexes (NPCs) perforate the nuclear envelope and serve as the primary transport gates for molecular exchange between nucleus and cytoplasm. Stripping the megadalton complex down to its most essential organizational elements, one can divide the NPC into scaffold components and the disordered elements attached to them that generate a selective barrier between compartments. These structural elements exhibit flexibility, which may hold a clue in understanding NPC assembly and function. Here we review the current status of NPC research with a focus on the functional implications of its structural and compositional heterogeneity.
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47
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Hampoelz B, Mackmull MT, Machado P, Ronchi P, Bui KH, Schieber N, Santarella-Mellwig R, Necakov A, Andrés-Pons A, Philippe JM, Lecuit T, Schwab Y, Beck M. Pre-assembled Nuclear Pores Insert into the Nuclear Envelope during Early Development. Cell 2016; 166:664-678. [PMID: 27397507 PMCID: PMC4967450 DOI: 10.1016/j.cell.2016.06.015] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 04/15/2016] [Accepted: 06/03/2016] [Indexed: 11/30/2022]
Abstract
Nuclear pore complexes (NPCs) span the nuclear envelope (NE) and mediate nucleocytoplasmic transport. In metazoan oocytes and early embryos, NPCs reside not only within the NE, but also at some endoplasmic reticulum (ER) membrane sheets, termed annulate lamellae (AL). Although a role for AL as NPC storage pools has been discussed, it remains controversial whether and how they contribute to the NPC density at the NE. Here, we show that AL insert into the NE as the ER feeds rapid nuclear expansion in Drosophila blastoderm embryos. We demonstrate that NPCs within AL resemble pore scaffolds that mature only upon insertion into the NE. We delineate a topological model in which NE openings are critical for AL uptake that nevertheless occurs without compromising the permeability barrier of the NE. We finally show that this unanticipated mode of pore insertion is developmentally regulated and operates prior to gastrulation. Annulate lamellae (AL) NPCs insert into the nuclear envelope during interphase AL-NPCs are pore scaffolds devoid of most transport channel nucleoporins NE-openings enable AL insertion, yet the permeability barrier remains unperturbed AL-NPC insertion operates only before gastrulation
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Affiliation(s)
- Bernhard Hampoelz
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany
| | - Marie-Therese Mackmull
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany
| | - Pedro Machado
- European Molecular Biology Laboratory, Electron Microscopy Core Facility, 69117 Heidelberg, Germany
| | - Paolo Ronchi
- European Molecular Biology Laboratory, Electron Microscopy Core Facility, 69117 Heidelberg, Germany
| | - Khanh Huy Bui
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany
| | - Nicole Schieber
- European Molecular Biology Laboratory, Cell Biology and Biophysics Unit, 69117 Heidelberg, Germany
| | | | - Aleksandar Necakov
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany
| | - Amparo Andrés-Pons
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany
| | | | - Thomas Lecuit
- Aix-Marseille Université, CNRS, IBDM UMR 7288, 13009 Marseille, France
| | - Yannick Schwab
- European Molecular Biology Laboratory, Electron Microscopy Core Facility, 69117 Heidelberg, Germany; European Molecular Biology Laboratory, Cell Biology and Biophysics Unit, 69117 Heidelberg, Germany
| | - Martin Beck
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, 69117 Heidelberg, Germany; European Molecular Biology Laboratory, Cell Biology and Biophysics Unit, 69117 Heidelberg, Germany.
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48
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Franks TM, Benner C, Narvaiza I, Marchetto MCN, Young JM, Malik HS, Gage FH, Hetzer MW. Evolution of a transcriptional regulator from a transmembrane nucleoporin. Genes Dev 2016; 30:1155-71. [PMID: 27198230 PMCID: PMC4888837 DOI: 10.1101/gad.280941.116] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 04/26/2016] [Indexed: 11/24/2022]
Abstract
Franks et al. identify a widely expressed variant of the transmembrane nucleoporin Pom121 (named sPom121, for “soluble Pom121”) that arose by genomic rearrangement before the divergence of hominoids. Instead of localizing to the NPC, sPom121 colocalizes and interacts with nucleoplasmic Nup98, a previously identified transcriptional regulator, at gene promoters to control transcription of its target genes in human cells. Nuclear pore complexes (NPCs) emerged as nuclear transport channels in eukaryotic cells ∼1.5 billion years ago. While the primary role of NPCs is to regulate nucleo–cytoplasmic transport, recent research suggests that certain NPC proteins have additionally acquired the role of affecting gene expression at the nuclear periphery and in the nucleoplasm in metazoans. Here we identify a widely expressed variant of the transmembrane nucleoporin (Nup) Pom121 (named sPom121, for “soluble Pom121”) that arose by genomic rearrangement before the divergence of hominoids. sPom121 lacks the nuclear membrane-anchoring domain and thus does not localize to the NPC. Instead, sPom121 colocalizes and interacts with nucleoplasmic Nup98, a previously identified transcriptional regulator, at gene promoters to control transcription of its target genes in human cells. Interestingly, sPom121 transcripts appear independently in several mammalian species, suggesting convergent innovation of Nup-mediated transcription regulation during mammalian evolution. Our findings implicate alternate transcription initiation as a mechanism to increase the functional diversity of NPC components.
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Affiliation(s)
- Tobias M Franks
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Chris Benner
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Iñigo Narvaiza
- Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Maria C N Marchetto
- Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Janet M Young
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Harmit S Malik
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA; Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
| | - Fred H Gage
- Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California 92037, USA; Center for Academic Research and Training in Anthropogeny (CARTA), La Jolla, California 92093, USA
| | - Martin W Hetzer
- Laboratory of Molecular and Cellular Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
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49
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Ptak C, Wozniak RW. Nucleoporins and chromatin metabolism. Curr Opin Cell Biol 2016; 40:153-160. [PMID: 27085162 DOI: 10.1016/j.ceb.2016.03.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 03/26/2016] [Accepted: 03/31/2016] [Indexed: 01/04/2023]
Abstract
Mounting evidence has implicated a group of proteins termed nucleoporins, or Nups, in various processes that regulate chromatin structure and function. Nups were first recognized as building blocks for nuclear pore complexes, but several members of this group of proteins also reside in the cytoplasm and within the nucleus. Moreover, many are dynamic and move between these various locations. Both at the nuclear envelope, as part of nuclear pore complexes, and within the nucleoplasm, Nups interact with protein complexes that function in gene transcription, chromatin remodeling, DNA repair, and DNA replication. Here, we review recent studies that provide further insight into the molecular details of these interactions and their role in regulating the activity of chromatin modifying factors.
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Affiliation(s)
- Christopher Ptak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
| | - Richard W Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7.
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50
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Faustino RS, Behfar A, Groenendyk J, Wyles SP, Niederlander N, Reyes S, Puceat M, Michalak M, Terzic A, Perez-Terzic C. Calreticulin secures calcium-dependent nuclear pore competency required for cardiogenesis. J Mol Cell Cardiol 2016; 92:63-74. [PMID: 26826378 DOI: 10.1016/j.yjmcc.2016.01.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 01/20/2016] [Accepted: 01/26/2016] [Indexed: 12/24/2022]
Abstract
Calreticulin deficiency causes myocardial developmental defects that culminate in an embryonic lethal phenotype. Recent studies have linked loss of this calcium binding chaperone to failure in myofibrillogenesis through an as yet undefined mechanism. The purpose of the present study was to identify cellular processes corrupted by calreticulin deficiency that precipitate dysregulation of cardiac myofibrillogenesis related to acquisition of cardiac phenotype. In an embryonic stem cell knockout model, calreticulin deficit (crt(-/-)) compromised nucleocytoplasmic transport of nuclear localization signal-dependent and independent pathways, disrupting nuclear import of the cardiac transcription factor MEF2C. The expression of nucleoporins and associated nuclear transport proteins in derived crt(-/-) cardiomyocytes revealed an abnormal nuclear pore complex (NPC) configuration. Altered protein content in crt(-/-) cells resulted in remodeled NPC architecture that caused decreased pore diameter and diminished probability of central channel occupancy versus wild type counterparts. Ionophore treatment of impaired calcium handling in crt(-/-) cells corrected nuclear pore microarchitecture and rescued nuclear import resulting in normalized myofibrillogenesis. Thus, calreticulin deficiency alters nuclear pore function and structure, impeding myofibrillogenesis in nascent cardiomyocytes through a calcium dependent mechanism. This essential role of calreticulin in nucleocytoplasmic communication competency ties its regulatory action with proficiency of cardiac myofibrillogenesis essential for proper cardiac development.
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Affiliation(s)
- Randolph S Faustino
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Atta Behfar
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Saranya P Wyles
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Nicolas Niederlander
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Santiago Reyes
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | | | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Andre Terzic
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA
| | - Carmen Perez-Terzic
- Center for Regenerative Medicine, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA; Department of Physical Medicine and Rehabilitation, Mayo Clinic, Rochester, MN, USA; Rehabilitation Research Center, Rochester, MN, USA.
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