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Lin H, Lin G, Lin L, Yang J, Yang D, Lin Q, Xu Y, Zeng Y. Comprehensive analysis of prognostic value and immune infiltration of Regulator of Chromosome Condensation 2 in lung adenocarcinoma. J Cancer 2024; 15:1901-1915. [PMID: 38434981 PMCID: PMC10905397 DOI: 10.7150/jca.91367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Background: Lung adenocarcinoma (LUAD) incidence and mortality take the leading place of most malignancies. Previous studies have revealed the regulator of chromosome condensation 1 (RCC1) family members played an essential role during tumorigenesis. However, its biological functions in LUAD still need further investigation. Methods: Several databases were applied to explore potential effects of RCC1 family members on LUAD, such as Oncomine, GEPIA, and cBioPortal. Real-time PCR and immunohistochemistry were used to verify the expression of RCC2 in stage I LUAD. H1975 and A549 were selected to explore the biological function of RCC2 in cellular malignant phenotype. Results: The expressions of RCC1 and RCC2 showed marked differences in malignant tissue compared to lung tissue. The higher the expression levels of RCC1 or RCC2 in LUAD patients, the shorter their overall survival (OS). In normal lung tissues, RCC1 expression was highly enriched in alveolar cells and endothelial cells. Compare with RCC1, RCC2 expression in normal lung tissue was significantly enriched in macrophages, B cells and granulocytes. Additionally, RCC2 expression level was correlated with multiple immune cell infiltration in LUAD. Moreover, the mutation or different sCNA status of RCC2 exerted influence on multiple immune cell infiltration distribution. We found that the upregulation of RCC1 and RCC2 were obviously related to TP53 mutation. GSEA analysis revealed that RCC2 was involved in the process of DNA replication, nucleotide excision repair and cell cycle, which might affect tumor progression through P53 signaling pathway. We further elucidated that downregulation of RCC2 could dramatically repress the migration and invasion of LUAD cells. Conclusions: The study demonstrated that RCC1 and RCC2 expression were markedly increased in early-stage of LUAD. Patients with high expression of RCC1 or RCC2 had a worse prognosis. Based on our analysis, RCC1 and RCC2 might exert influence on LUAD process through DNA replication, nucleotide excision repair and cell cycle, as well as cells migration and invasion. Different from RCC1, RCC2 also involved in immune infiltration. These analyses provided a novel insight into the identification of diagnostic biomarker.
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Affiliation(s)
- Hai Lin
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
- The Second Clinical College, Fujian Medical University, Fuzhou, China
| | - Guofu Lin
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
- The Second Clinical College, Fujian Medical University, Fuzhou, China
| | - Lanlan Lin
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
- The Second Clinical College, Fujian Medical University, Fuzhou, China
| | - Jiansheng Yang
- Department of thoracic surgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
| | - Dongyong Yang
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
| | - Qinhui Lin
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
| | - Yuan Xu
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
| | - Yiming Zeng
- Department of Respiratory Pulmonary and Critical Care Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian province, 362000, China
- Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian province, 362000, China
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Yeo EJ, Shin MJ, Youn GS, Park JH, Yeo HJ, Kwon HJ, Lee LR, Kim NY, Kwon SY, Kim SM, Lee J, Lee KW, Lee CH, Cho YJ, Kwon OS, Kim DW, Jung HY, Eum WS, Choi SY. Tat-RAN attenuates brain ischemic injury in hippocampal HT-22 cells and ischemia animal model. Neurochem Int 2023; 167:105538. [PMID: 37207854 DOI: 10.1016/j.neuint.2023.105538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/30/2023] [Accepted: 05/07/2023] [Indexed: 05/21/2023]
Abstract
Oxidative stress plays a key role in the pathogenesis of neuronal injury, including ischemia. Ras-related nuclear protein (RAN), a member of the Ras superfamily, involves in a variety of biological roles, such as cell division, proliferation, and signal transduction. Although RAN reveals antioxidant effect, its precise neuroprotective mechanisms are still unclear. Therefore, we investigated the effects of RAN on HT-22 cell which were exposed to H2O2-induced oxidative stress and ischemia animal model by using the cell permeable Tat-RAN fusion protein. We showed that Tat-RAN transduced into HT-22 cells, and markedly inhibited cell death, DNA fragmentation, and reactive oxygen species (ROS) generation under oxidative stress. This fusion protein also controlled cellular signaling pathways, including mitogen-activated protein kinases (MAPKs), NF-κB, and apoptosis (Caspase-3, p53, Bax and Bcl-2). In the cerebral forebrain ischemia animal model, Tat-RAN significantly inhibited both neuronal cell death, and astrocyte and microglia activation. These results indicate that RAN significantly protects against hippocampal neuronal cell death, suggesting Tat-RAN will help to develop the therapies for neuronal brain diseases including ischemic injury.
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Affiliation(s)
- Eun Ji Yeo
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Min Jea Shin
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Gi Soo Youn
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Jung Hwan Park
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Hyeon Ji Yeo
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Hyun Jung Kwon
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Lee Re Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Na Yeon Kim
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Su Yeon Kwon
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Su Min Kim
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Jaehak Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Keun Wook Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Chan Hee Lee
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea
| | - Yong-Jun Cho
- Department of Neurosurgery, Hallym University Medical Center, Chuncheon, 24253, South Korea
| | - Oh-Shin Kwon
- School of Life Sciences, College of Natural Sciences Kyungpook National University, Taegu, 41566, South Korea
| | - Dae Won Kim
- Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung-Wonju National University, Gangneung, 25457, South Korea
| | - Hyo Young Jung
- Department of Veterinary Medicine & Institute of Veterinary Science, Chungnam National University, Daejeon, 34134, South Korea
| | - Won Sik Eum
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea.
| | - Soo Young Choi
- Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, 24252, South Korea.
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3
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Meng Q, Wu M, Shang Z, Zhang Z, Zhang R. Responsive gadolinium(III) complex-based small molecule magnetic resonance imaging probes: Design, mechanism and application. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214398] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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4
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Phosphorylation of RCC1 on Serine 11 Facilitates G1/S Transition in HPV E7-Expressing Cells. Biomolecules 2021; 11:biom11070995. [PMID: 34356619 PMCID: PMC8301946 DOI: 10.3390/biom11070995] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 07/01/2021] [Accepted: 07/01/2021] [Indexed: 11/25/2022] Open
Abstract
Persistent infection of high-risk human papillomavirus (HR-HPV) plays a causal role in cervical cancer. Regulator of chromosome condensation 1 (RCC1) is a critical cell cycle regulator, which undergoes a few post-translational modifications including phosphorylation. Here, we showed that serine 11 (S11) of RCC1 was phosphorylated in HPV E7-expressing cells. However, S11 phosphorylation was not up-regulated by CDK1 in E7-expressing cells; instead, the PI3K/AKT/mTOR pathway promoted S11 phosphorylation. Knockdown of AKT or inhibition of the PI3K/AKT/mTOR pathway down-regulated phosphorylation of RCC1 S11. Furthermore, S11 phosphorylation occurred throughout the cell cycle, and reached its peak during the mitosis phase. Our previous data proved that RCC1 was necessary for the G1/S cell cycle progression, and in the present study we showed that the RCC1 mutant, in which S11 was mutated to alanine (S11A) to mimic non-phosphorylation status, lost the ability to facilitate G1/S transition in E7-expressing cells. Moreover, RCC1 S11 was phosphorylated by the PI3K/AKT/mTOR pathway in HPV-positive cervical cancer SiHa and HeLa cells. We conclude that S11 of RCC1 is phosphorylated by the PI3K/AKT/mTOR pathway and phosphorylation of RCC1 S11 facilitates the abrogation of G1 checkpoint in HPV E7-expressing cells. In short, our study explores a new role of RCC1 S11 phosphorylation in cell cycle regulation.
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Genome-wide identification of Ran GTPase family genes from wheat (T. aestivum) and their expression profile during developmental stages and abiotic stress conditions. Funct Integr Genomics 2021; 21:239-250. [PMID: 33609188 DOI: 10.1007/s10142-021-00773-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 02/02/2021] [Accepted: 02/09/2021] [Indexed: 10/22/2022]
Abstract
Maintenance of growth is important for sustaining yield under stress conditions. Hence, identification of genes involved in cell division and growth under abiotic stress is utmost important. Ras-related nuclear protein (Ran) is a small GTPase required for nucleocytoplasmic transport, mitotic progression, and nuclear envelope assembly in plants. In the present study, two Ran GTPase genes TaRAN1 and TaRAN2 were identified though genome-wide analysis in wheat (T. aestivum). Comparative analysis of Ran GTPases from wheat, barley, rice, maize, sorghum, and Arabidopsis revealed similar gene structure within phylogenetic clades and highly conserved protein structure. Expression analysis from expVIP platform showed ubiquitous expression of TaRAN genes across tissues and developmental stages. Under biotic and abiotic stresses, TaRAN1 expression was largely unaltered, while TaRAN2 showed stress specific response. In qRT-PCR analysis, TaRAN1 showed significantly higher expression as compared to TaRAN2 in shoot and root at seedling, vegetative, and reproductive stages. During progressive drought stress, TaRAN1 and TaRAN2 expression increase during early stress and restored to control level expression at higher stress levels in shoot. The steady-state level of transcripts was maintained to that of control in roots under drought stress. Under cold stress, expression of both the TaRAN genes decreased significantly at 3 h and became similar to control at 6 h in shoots, while salt stress significantly reduced the expression of TaRAN genes in shoots. The analysis suggests differential regulation of TaRAN genes under developmental stages and abiotic stresses. Delineating the molecular functions of Ran GTPases will help unravel the mechanism of stress induced growth inhibition in wheat.
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Jia N, Zhang X, Li W, Chen D, Hu H. Phospholipid-Coated Guanosine Diphosphate Auxiliary CaP Active Nanoparticles Can Systematically Improve the Efficiency of Gene Therapy for Cancer Disease. ACS Biomater Sci Eng 2020; 6:2107-2116. [PMID: 33455334 DOI: 10.1021/acsbiomaterials.0c00316] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Endogenous active substance guanosine diphosphate (GDP) is involved in the physiological process of DNA transfection and expression in the cytoplasm by binding to Ran proteins. To substantially improve the gene delivery efficiency of nanoparticles, phospholipid-coated Ca(P-GDP)/pDNA/NLS hybrid nanoparticles were prepared using GDP as a common biophosphorus source based on the biological process of exogenous gene expression in the cells. This nanoparticle has a relative uniform particle size distribution and in vitro stability. The addition of GDP in nanoparticles significantly enhanced the gene expression efficiency with good biocompatibility. Moreover, an in vivo study further verified that hybrid nanoparticles were more effective in increasing the p53 gene expression, thus significantly inhibiting the tumor growth in the heterotopic tumor model of nude mice. These results demonstrated that phospholipid-coated Ca(P-GDP) nanoparticles were a potential nonviral gene vector to promote gene expression. The experimental results confirmed the feasibility of designing a delivery system based on active substances and provided a new solution to improve the transfection efficiency of gene drugs.
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Affiliation(s)
- Nan Jia
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, PR China
| | - Xirui Zhang
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, PR China
| | - Wenpan Li
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, PR China
| | - Dawei Chen
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, PR China
| | - Haiyang Hu
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, PR China
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7
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Wang M, Xu P, Zhu Z. Regulation of signal transduction in Coilia nasus during migration. Genomics 2019; 112:55-64. [PMID: 31404627 DOI: 10.1016/j.ygeno.2019.07.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 07/31/2019] [Accepted: 07/31/2019] [Indexed: 12/11/2022]
Abstract
Coilia nasus (C. nasus) is an important anadromous fish species that resides in the Yangtze River in China. However, wild C. nasus have suffered serious damage as a result of overfishing and environmental pollution. We performed comparative liver and brain transcriptome analyses of C. nasus from the Jingjiang (JJ) and Dangtu (DT) sections of the Yangtze River. The results indicate that, during migration, most signal pathways in C. nasus livers were downregulated, indicating that the liver has a function in energy conservation. The brain assumes more of a regulatory role, and the signal transduction pathways and relevant genes were upregulated. This study provides genetic information for screening the key regulatory genes of gonad development of C. nasus, which can be applied in the artificial breeding of C. nasus, providing high-quality fish fry for proliferation and release and may also contribute to efforts towards the restoration of wild C. nasus.
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Affiliation(s)
- Meiyao Wang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu Province, China; Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, Jiangsu Province, China; Aquatic Animal Genome Center of Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214128, Jiangsu Province, China
| | - Pao Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu Province, China; Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, Jiangsu Province, China; Aquatic Animal Genome Center of Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214128, Jiangsu Province, China.
| | - Zhixiang Zhu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu Province, China
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Jevtić P, Schibler AC, Wesley CC, Pegoraro G, Misteli T, Levy DL. The nucleoporin ELYS regulates nuclear size by controlling NPC number and nuclear import capacity. EMBO Rep 2019; 20:embr.201847283. [PMID: 31085625 DOI: 10.15252/embr.201847283] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 04/09/2019] [Accepted: 04/11/2019] [Indexed: 12/13/2022] Open
Abstract
How intracellular organelles acquire their characteristic sizes is a fundamental question in cell biology. Given stereotypical changes in nuclear size in cancer, it is important to understand the mechanisms that control nuclear size in human cells. Using a high-throughput imaging RNAi screen, we identify and mechanistically characterize ELYS, a nucleoporin required for post-mitotic nuclear pore complex (NPC) assembly, as a determinant of nuclear size in mammalian cells. ELYS knockdown results in small nuclei, reduced nuclear lamin B2 localization, lower NPC density, and decreased nuclear import. Increasing nuclear import by importin α overexpression rescues nuclear size and lamin B2 import, while inhibiting importin α/β-mediated nuclear import decreases nuclear size. Conversely, ELYS overexpression increases nuclear size, enriches nuclear lamin B2 at the nuclear periphery, and elevates NPC density and nuclear import. Consistent with these observations, knockdown or inhibition of exportin 1 increases nuclear size. Thus, we identify ELYS as a novel positive effector of mammalian nuclear size and propose that nuclear size is sensitive to NPC density and nuclear import capacity.
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Affiliation(s)
- Predrag Jevtić
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
| | | | - Chase C Wesley
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
| | - Gianluca Pegoraro
- High Throughput Imaging Facility (HiTIF), National Cancer Institute, NIH, Bethesda, MD, USA
| | - Tom Misteli
- National Cancer Institute, NIH, Bethesda, MD, USA
| | - Daniel L Levy
- Department of Molecular Biology, University of Wyoming, Laramie, WY, USA
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Ran is associated with chromosomes during starfish oocyte meiosis and embryonic mitoses. ZYGOTE 2018. [DOI: 10.1017/s0967199400130540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Ran is an abundant small G protein that has a central role in nuclear transport during interphase. Ran function depends on distinct pools of RanGTP in the nucleus and RanGDP in the cytoplasm, which are maintained by compartmentalisation of the nucleotide exchange and GTPase activating proteins for Ran. RCC1 (Regulator of Chromosome Condensation) is the only known guanine nucleotide exchange factor for Ran and is associated with chromatin. RanGAPl together with RanBPl are the primary GTPase activator proteins and are located in the cytoplasm.Ran function in nuclear transport is clearly inactivated after the nuclear envelope has disassembled during mitosis. There is now evidence that Ran plays a role in organising the spindle. Experiments using well-characterised cell-free extracts from meiotic metaphase II arrested Xenopus eggs suggest that Ran regulates microtubules involved in spindle assembly (Carazo-Salas et al., 1999; Kalab et al., 1999; Ohba et al., 1999; Wilde & Zheng, 1999). These experiments demonstrate that high levels of RanGTP or GTP-locked forms of Ran result in aster formation and can cause formation of bipolar spindles in the absence of centrosomes or chromosomes. In contrast, reduction of RanGTP blocks centriole- and chromatin-dependent aster formation.
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Qiao L, Zheng J, Tian Y, Zhang Q, Wang X, Chen JJ, Zhang W. Regulator of chromatin condensation 1 abrogates the G1 cell cycle checkpoint via Cdk1 in human papillomavirus E7-expressing epithelium and cervical cancer cells. Cell Death Dis 2018; 9:583. [PMID: 29789527 PMCID: PMC5964113 DOI: 10.1038/s41419-018-0584-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 03/31/2018] [Accepted: 04/06/2018] [Indexed: 01/01/2023]
Abstract
Regulator of chromatin condensation 1 (RCC1) is a major guanine-nucleotide exchange factor for Ran GTPase and plays key roles in nucleo-cytoplasmic transport, mitosis, and nuclear envelope assembly. RCC1 is known to be a critical cell cycle regulator whose loss causes G1 phase arrest, but the molecular basis for this regulation is poorly understood. Furthermore, little is known about the relationship between RCC1 and carcinomas. Human papillomavirus (HPV) infection is highly associated with the development of cervical cancer. The expression and function of RCC1 in HPV-related cervical cancer and cell cycle regulation have not yet been explored. In this study, we first observed that RCC1 immunostaining was mildly increased in cervical cancer tissues and significantly upregulated in HPV E7-expressing cells; this localization was primarily nuclear. We showed that the transcription factor c-Jun transcriptionally upregulates RCC1 via a direct interaction with the RCC1 promoter. Moreover, siRNA-mediated knockdown of RCC1 inhibited G1/S cell cycle progression and DNA synthesis, while overexpression of RCC1 abrogated the G1 checkpoint. RCC1 knockdown downregulated the protein levels of the transcription factor E2F1, especially nuclear E2F1, by promoting its degradation in HPV E7-expressing cells. Overexpression of E2F1 rescued RCC1 knockdown-mediated inhibition of G1/S progression. Additionally, we showed that cyclin-dependent kinase 1 (Cdk1), a known target of E2F1, is involved in G1 checkpoint regulation, as Cdk1 knockdown hindered G1/S progression, while Cdk1 overexpression rescued RCC1 knockdown-mediated effect on G1 cell cycle progression. Furthermore, RCC1 knockdown reduced HPV E7 protein levels, which may in turn downregulate E2F1. Our study explores the function of RCC1 in G1/S cell cycle progression and suggests that RCC1 may be involved in HPV E7-mediated genomic instability.
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Affiliation(s)
- Lijun Qiao
- Cancer Research Center and Department of Microbiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Jingyi Zheng
- Department of Microbiology and Key Laboratory of Infection and Immunity of Shandong Province, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Yonghao Tian
- Department of Orthopedic Surgery, Qilu Hospital Affiliated Shandong University, Jinan, Shandong, China
| | - Qishu Zhang
- Cancer Research Center and Department of Microbiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Xiao Wang
- Institute of Pathobiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Jason J Chen
- Cancer Research Center and Department of Microbiology, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China
| | - Weifang Zhang
- Department of Microbiology and Key Laboratory of Infection and Immunity of Shandong Province, School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China.
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Korwek Z, Tudelska K, Nałęcz-Jawecki P, Czerkies M, Prus W, Markiewicz J, Kochańczyk M, Lipniacki T. Importins promote high-frequency NF-κB oscillations increasing information channel capacity. Biol Direct 2016; 11:61. [PMID: 27835978 PMCID: PMC5106790 DOI: 10.1186/s13062-016-0164-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 10/29/2016] [Indexed: 12/18/2022] Open
Abstract
Background Importins and exportins influence gene expression by enabling nucleocytoplasmic shuttling of transcription factors. A key transcription factor of innate immunity, NF-κB, is sequestered in the cytoplasm by its inhibitor, IκBα, which masks nuclear localization sequence of NF-κB. In response to TNFα or LPS, IκBα is degraded, which allows importins to bind NF-κB and shepherd it across nuclear pores. NF-κB nuclear activity is terminated when newly synthesized IκBα enters the nucleus, binds NF-κB and exportin which directs the complex to the cytoplasm. Although importins/exportins are known to regulate spatiotemporal kinetics of NF-κB and other transcription factors governing innate immunity, the mechanistic details of these interactions have not been elucidated and mathematically modelled. Results Based on our quantitative experimental data, we pursue NF-κB system modelling by explicitly including NF-κB–importin and IκBα–exportin binding to show that the competition between importins and IκBα enables NF-κB nuclear translocation despite high levels of IκBα. These interactions reduce the effective relaxation time and allow the NF-κB regulatory pathway to respond to recurrent TNFα pulses of 45-min period, which is about twice shorter than the characteristic period of NF-κB oscillations. By stochastic simulations of model dynamics we demonstrate that randomly appearing, short TNFα pulses can be converted to essentially digital pulses of NF-κB activity, provided that intervals between input pulses are not shorter than 1 h. Conclusions By including interactions involving importin-α and exportin we bring the modelling of spatiotemporal kinetics of transcription factors to a more mechanistic level. Basing on the analysis of the pursued model we estimated the information transmission rate of the NF-κB pathway as 1 bit per hour. Reviewers This article was reviewed by Marek Kimmel, James Faeder and William Hlavacek. Electronic supplementary material The online version of this article (doi:10.1186/s13062-016-0164-z) contains supplementary material.
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Affiliation(s)
- Zbigniew Korwek
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Karolina Tudelska
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Paweł Nałęcz-Jawecki
- College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences, University of Warsaw, Warsaw, Poland
| | - Maciej Czerkies
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Wiktor Prus
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Joanna Markiewicz
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Marek Kochańczyk
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
| | - Tomasz Lipniacki
- Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland.
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Ras-Related Nuclear Protein Ran3B Gene Is Involved in Hormone Responses in the Embryogenic Callus of Dimocarpus longan Lour. Int J Mol Sci 2016; 17:ijms17060873. [PMID: 27271605 PMCID: PMC4926407 DOI: 10.3390/ijms17060873] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 05/15/2016] [Accepted: 05/23/2016] [Indexed: 11/17/2022] Open
Abstract
Ras-related guanosine triphosphate (GTP)-binding nuclear protein (Ran) GTPases function as molecular switches and regulate diverse cellular events in eukaryotes. Our previous work suggested that DlRan3B is active during longan (Dimocarpus longan Lour.) somatic embryogenesis (SE) processes. Herein, subcellular localization of DlRan3B was found to be localized in the nucleus and expression profiling of DlRan3B was performed during longan SE and after exposure to plant hormones (indoleacetic acid (IAA), gibberellin A3 (GA3), salicylic acid (SA), methyl jasmonte (MeJA), and abscisic acid (ABA)). We cloned and sequenced 1569 bp of 5′-flanking sequence of DlRan3B (GenBank: JQ279697). Bioinformatic analysis indicated that the promoter contained plant hormone-related regulatory elements. Deletion analysis and responses to hormones identified stimulative and repressive regulatory elements in the DlRan3B promoter. The key elements included those responding to auxin, gibberellin, SA, MeJA, and ABA. DlRan3B was located in the nucleus and accumulated in the late stage of longan SE. The expression of DlRan3B was significantly induced by IAA, GA3, and ABA, but suppressed by SA and MeJA. Promoter transcription was induced by IAA and GA3, but suppressed by SA. Thus, DlRan3B might participate in auxin, gibberellin, and ABA responses during longan late SE, and DlRan3B is involved in phytohormone responsiveness.
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The Small G Protein AtRAN1 Regulates Vegetative Growth and Stress Tolerance in Arabidopsis thaliana. PLoS One 2016; 11:e0154787. [PMID: 27258048 PMCID: PMC4892486 DOI: 10.1371/journal.pone.0154787] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/19/2016] [Indexed: 12/02/2022] Open
Abstract
The evolutionarily conserved small G-protein Ran plays important role in nuclear translocation of proteins, cell cycle regulation, and nuclear envelope maintenance in mammalian cells and yeast. Arabidopsis Ran proteins are encoded by a family of four genes and are highly conserved at the protein level. However, their biological functions are poorly understood. We report here that AtRAN1 plays an important role in vegetative growth and the molecular improvement of stress tolerance in Arabidopsis. AtRAN1 overexpression promoted vegetative growth and enhanced abiotic tolerance, while the atran1 atran3 double mutant showed higher freezing sensitivity than WT. The AtRAN1 gene is ubiquitously expressed in plants, and the expression levels are higher in the buds, flowers and siliques. Subcellular localization results showed that AtRAN1 is mainly localized in the nucleus, with some present in the cytoplasm. AtRAN1 could maintain cell division and cell cycle progression and promote the formation of an intact nuclear envelope, especially under freezing conditions.
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Up-regulated expression of Ran reveals its potential role to deltamethrin stress in Kc cells. Gene 2016; 583:1-7. [DOI: 10.1016/j.gene.2016.02.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/22/2016] [Accepted: 02/23/2016] [Indexed: 12/22/2022]
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Abstract
According to the standard model of G protein-coupled receptor (GPCR) signaling, GPCRs are localized to the cell membrane where they respond to extracellular signals. Stimulation of GPCRs leads to the activation of heterotrimeric G proteins and their intracellular signaling pathways. However, this model fails to accommodate GPCRs, G proteins, and their downstream effectors that are found on the nuclear membrane or in the nucleus. Evidence from isolated nuclei indicates the presence of GPCRs on the nuclear membrane that can activate similar G protein-dependent signaling pathways in the nucleus as at the cell surface. These pathways also include activation of cyclic adenosine monophosphate, calcium and nitric oxide synthase signaling in cardiomyocytes. In addition, a number of distinct heterotrimeric and monomeric G proteins have been found in the nucleus of various cell types. This review will focus on understanding the function of nuclear G proteins with a focus on cardiac signaling where applicable.
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DlRan3A is involved in hormone, light, and abiotic stress responses in embryogenic callus of Dimocarpus longan Lour. Gene 2015; 569:267-75. [DOI: 10.1016/j.gene.2015.06.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 05/11/2015] [Accepted: 05/27/2015] [Indexed: 12/21/2022]
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Small GTP-binding protein Ran is regulated by posttranslational lysine acetylation. Proc Natl Acad Sci U S A 2015; 112:E3679-88. [PMID: 26124124 DOI: 10.1073/pnas.1505995112] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ran is a small GTP-binding protein of the Ras superfamily regulating fundamental cellular processes: nucleo-cytoplasmic transport, nuclear envelope formation and mitotic spindle assembly. An intracellular Ran•GTP/Ran•GDP gradient created by the distinct subcellular localization of its regulators RCC1 and RanGAP mediates many of its cellular effects. Recent proteomic screens identified five Ran lysine acetylation sites in human and eleven sites in mouse/rat tissues. Some of these sites are located in functionally highly important regions such as switch I and switch II. Here, we show that lysine acetylation interferes with essential aspects of Ran function: nucleotide exchange and hydrolysis, subcellular Ran localization, GTP hydrolysis, and the interaction with import and export receptors. Deacetylation activity of certain sirtuins was detected for two Ran acetylation sites in vitro. Moreover, Ran was acetylated by CBP/p300 and Tip60 in vitro and on transferase overexpression in vivo. Overall, this study addresses many important challenges of the acetylome field, which will be discussed.
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Disruption of the ran system by cysteine oxidation of the nucleotide exchange factor RCC1. Mol Cell Biol 2014; 35:566-81. [PMID: 25452301 DOI: 10.1128/mcb.01133-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Transport regulation by the Ran GTPase requires its nuclear localization and GTP loading by the chromatin-associated exchange factor RCC1. These reactions generate Ran protein and Ran nucleotide gradients between the nucleus and the cytoplasm. Cellular stress disrupts the Ran gradients, but the specific mechanisms underlying this disruption have not been elucidated. We used biochemical approaches to determine how oxidative stress disrupts the Ran system. RCC1 exchange activity was reduced by diamide-induced oxidative stress and restored with dithiothreitol. Using mass spectrometry, we found that multiple solvent-exposed cysteines in RCC1 are oxidized in cells treated with diamide. The cysteines oxidized in RCC1 included Cys93, which is solvent exposed and unique because it becomes buried upon contact with Ran. A Cys93Ser substitution dramatically reduced exchange activity through an effect on RCC1 binding to RanGDP. Diamide treatment reduced the size of the mobile fraction of RCC1-green fluorescent protein in cells and inhibited nuclear import in digitonin-permeabilized cell assays. The Ran protein gradient was also disrupted by UV-induced stress but without affecting RCC1 exchange activity. Our data suggest that stress can disrupt the Ran gradients through RCC1-dependent and RCC1-independent mechanisms, possibly dependent on the particular stress condition.
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Bernis C, Swift-Taylor B, Nord M, Carmona S, Chook YM, Forbes DJ. Transportin acts to regulate mitotic assembly events by target binding rather than Ran sequestration. Mol Biol Cell 2014; 25:992-1009. [PMID: 24478460 PMCID: PMC3967982 DOI: 10.1091/mbc.e13-08-0506] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Transportin-specific molecular tools are used to show that the mitotic cell contains importin β and transportin “global positioning system” pathways that are mechanistically parallel. Transportin works to control where the spindle, nuclear membrane, and nuclear pores are formed by directly affecting assembly factor function. The nuclear import receptors importin β and transportin play a different role in mitosis: both act phenotypically as spatial regulators to ensure that mitotic spindle, nuclear membrane, and nuclear pore assembly occur exclusively around chromatin. Importin β is known to act by repressing assembly factors in regions distant from chromatin, whereas RanGTP produced on chromatin frees factors from importin β for localized assembly. The mechanism of transportin regulation was unknown. Diametrically opposed models for transportin action are as follows: 1) indirect action by RanGTP sequestration, thus down-regulating release of assembly factors from importin β, and 2) direct action by transportin binding and inhibiting assembly factors. Experiments in Xenopus assembly extracts with M9M, a superaffinity nuclear localization sequence that displaces cargoes bound by transportin, or TLB, a mutant transportin that can bind cargo and RanGTP simultaneously, support direct inhibition. Consistently, simple addition of M9M to mitotic cytosol induces microtubule aster assembly. ELYS and the nucleoporin 107–160 complex, components of mitotic kinetochores and nuclear pores, are blocked from binding to kinetochores in vitro by transportin, a block reversible by M9M. In vivo, 30% of M9M-transfected cells have spindle/cytokinesis defects. We conclude that the cell contains importin β and transportin “global positioning system”or “GPS” pathways that are mechanistically parallel.
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Affiliation(s)
- Cyril Bernis
- Section of Cell and Developmental Biology, Division of Biological Sciences 0347, University of California-San Diego, La Jolla, CA 92093-0347 Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041
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Karunakaran SC, Paul AK, Ramaiah D. Effective discrimination of GTP from ATP by a cationic tentacle porphyrin through “turn-on” fluorescence intensity. RSC Adv 2014. [DOI: 10.1039/c4ra04672b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cationic porphyrin selectively recognises guanosine based nucleotides was utilized as fluorescence “turn-on” probe to discriminate GTP from ATP through FID assay.
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Affiliation(s)
- Suneesh C. Karunakaran
- Photosciences and Photonics
- Chemical Sciences and Technology Division
- CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Trivandrum–695019, India
| | - Albish K. Paul
- Photosciences and Photonics
- Chemical Sciences and Technology Division
- CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Trivandrum–695019, India
| | - Danaboyina Ramaiah
- Photosciences and Photonics
- Chemical Sciences and Technology Division
- CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Trivandrum–695019, India
- CSIR-North East Institute of Science and Technology (CSIR-NEIST)
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Nagai M, Yoneda Y. Downregulation of the small GTPase ras-related nuclear protein accelerates cellular ageing. Biochim Biophys Acta Gen Subj 2013; 1830:2813-9. [PMID: 23160023 DOI: 10.1016/j.bbagen.2012.11.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 09/26/2012] [Accepted: 11/09/2012] [Indexed: 11/30/2022]
Abstract
BACKGROUND The small GTPase Ran, Ras-related nuclear protein, plays important roles in multiple fundamental cellular functions such as nucleocytoplasmic transport, mitotic spindle assembly, and nuclear envelope formation, by binding to either GTP or GDP as a molecular switch. Although it has been clinically demonstrated that Ran is highly expressed in multiple types of cancer cells and specimens, the physiological significance of Ran expression levels is unknown. METHODS During the long-term culture of normal mammalian cells, we found that the endogenous Ran level gradually reduced in a passage-dependent manner. To examine the physiological significance of Ran reduction, we first performed small interfering RNA (siRNA)-mediated abrogation of Ran in human diploid fibroblasts. RESULTS Ran-depleted cells showed several senescent phenotypes. Furthermore, we found that nuclear accumulation of importin alpha, which was also observed in cells treated with siRNA against CAS, a specific export factor for importin alpha, occurred in the Ran-depleted cells before the cells showed senescent phenotypes. Further, the CAS-depleted cells also exhibited cellular senescence. Indeed, importin alpha showed predominant nuclear localisation in a passage-dependent manner. CONCLUSIONS Reduction in Ran levels causes cytoplasmic decrease and nuclear accumulation of importin alpha leading to cellular senescence in normal cells. GENERAL SIGNIFICANCE The amount of intracellular Ran may be critically related to cell fate determination, such as malignant transformation and senescence. The cellular ageing process may proceed through gradual regression of Ran-dependent nucleocytoplasmic transport competency.
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Affiliation(s)
- Masahiro Nagai
- Biomolecular Dynamics Laboratory, Department of Frontier Biosciences, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamada-oka, Suita, Osaka 565-0871, Japan
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Hodas JJL, Nehring A, Höche N, Sweredoski MJ, Pielot R, Hess S, Tirrell DA, Dieterich DC, Schuman EM. Dopaminergic modulation of the hippocampal neuropil proteome identified by bioorthogonal noncanonical amino acid tagging (BONCAT). Proteomics 2012; 12:2464-76. [PMID: 22744909 DOI: 10.1002/pmic.201200112] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Local protein synthesis and its activity-dependent modulation via dopamine receptor stimulation play an important role in synaptic plasticity - allowing synapses to respond dynamically to changes in their activity patterns. We describe here the metabolic labeling, enrichment, and MS-based identification of candidate proteins specifically translated in intact hippocampal neuropil sections upon treatment with the selective D1/D5 receptor agonist SKF81297. Using the noncanonical amino acid azidohomoalanine and click chemistry, we identified over 300 newly synthesized proteins specific to dendrites and axons. Candidates specific for the SKF81297-treated samples were predominantly involved in protein synthesis and synapse-specific functions. Furthermore, we demonstrate a dendrite-specific increase in proteins synthesis upon application of SKF81297. This study provides the first snapshot in the dynamics of the dopaminergic hippocampal neuropil proteome.
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Affiliation(s)
- Jennifer J L Hodas
- Division of Biology, California Institute of Technology, Pasadena, CA, USA
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Watanabe M, Takemasa I, Kawaguchi N, Miyake M, Nishimura N, Matsubara T, Matsuo EI, Sekimoto M, Nagai K, Matsuura N, Monden M, Nishimura O. An application of the 2-nitrobenzenesulfenyl method to proteomic profiling of human colorectal carcinoma: A novel approach for biomarker discovery. Proteomics Clin Appl 2012; 2:925-35. [PMID: 21136890 DOI: 10.1002/prca.200780111] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In the development of novel biomarkers, the proteomic approach is advantageous because using it the cancer-associated proteins can be directly identified. We previously developed a 2-nitrobenzenesulfenyl (NBS) method to improve quantitative proteome analysis. Here, we applied this method to proteomic profiling of colorectal carcinoma (CRC) to identify novel proteins with altered expression in CRC. Each pair of tumor and normal tissue specimens from 12 CRC patients was analyzed, and approximately 5000 NBS-labeled paired peaks were quantified. Peaks with altered signal intensities (>1.5-fold) and occurring frequently in the samples (>70%) were selected, and 128 proteins were identified by MS/MS analyses as differentially expressed proteins in CRC tissues. Many proteins were newly revealed to be CRC related; 30 were reported in earlier studies of CRC. Six proteins that were up-regulated in CRC (ZYX, RAN, RCN1, AHCY, LGALS1, and VIM) were further characterized and validated by Western blot and immunohistochemistry. All six were found to be CRC-localized, either in cancer cells or in stroma cells near the cancer cells. These results indicate that the proteins identified in this study are novel candidates for CRC markers, and that the NBS method is useful in proteome mining to discover novel biomarkers.
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Affiliation(s)
- Makoto Watanabe
- Division of Disease Proteomics, Institute for Protein Research, Osaka University, Osaka, Japan; Life Science Laboratory, Shimadzu Corporation, Kyoto, Japan
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Fan H, Lu Y, Qin H, Zhou Y, Gu Y, Zhou J, Wang X, Fan D. High Ran level is correlated with poor prognosis in patients with colorectal cancer. Int J Clin Oncol 2012; 18:856-63. [PMID: 22956174 DOI: 10.1007/s10147-012-0465-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 07/30/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND The Ras-like nuclear protein (Ran) is involved in the regulation of nuclear transport, microtubule nucleation and dynamics, and spindle assembly. Its fundamental function is nucleocytoplasmic transport of RNA and proteins. The expression and potential role of Ran in colorectal cancer (CRC) remain unclear. The aim of this study was to investigate the relationship between Ran expression and CRC characteristics. The potential role of Ran as a prognostic indicator was also evaluated. METHODS We used immunohistochemistry and western blotting to detect Ran expression in 287 CRC tissues. The relationships between Ran expression and clinicopathological characteristics and overall survival rate were statistically analyzed. RESULTS CRC tissues had significantly higher Ran expression than normal colorectal epithelial cells. Ran was positively correlated with depth of invasion, lymph node metastases, distant metastases, tumor differentiation, and tumor-node-metastasis stage. However, no correlation was found between Ran expression and patient age or sex. The overall survival rate was consistently and significantly lower in patients with Ran-positive tumors than in those with Ran-negative tumors. CONCLUSION Our findings emphasize the important role of Ran in differentiation, disease stage, and metastasis in human CRC. Ran may play an important role in the development of CRC and may serve as a novel prognostic indicator of CRC.
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Affiliation(s)
- Hongwei Fan
- State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 127 West Changle Road, Xi'an, Shaanxi, 710032, China
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Milano SK, Kwon W, Pereira R, Antonyak MA, Cerione RA. Characterization of a novel activated Ran GTPase mutant and its ability to induce cellular transformation. J Biol Chem 2012; 287:24955-66. [PMID: 22679017 DOI: 10.1074/jbc.m111.306514] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Ran (Ras-related nuclear) protein, a member of the Ras superfamily of GTPases, is best known for its roles in nucleocytoplasmic transport, mitotic spindle fiber assembly, and nuclear envelope formation. Recently, we have shown that the overexpression of Ran in fibroblasts induces cellular transformation and tumor formation in mice (Ly, T. K., Wang, J., Pereira, R., Rojas, K. S., Peng, X., Feng, Q., Cerione, R. A., and Wilson, K. F. (2010) J. Biol. Chem. 285, 5815-5826). Here, we describe a novel activated Ran mutant, Ran(K152A), which is capable of an increased rate of GDP-GTP exchange and an accelerated GTP binding/GTP hydrolytic cycle compared with wild-type Ran. We show that its expression in NIH-3T3 fibroblasts induces anchorage-independent growth and stimulates cell invasion, as well as activates signaling pathways that lead to extracellular regulated kinase (ERK) activity. Furthermore, Ran(K152A) expression in the human mammary SKBR3 adenocarcinoma cell line gives rise to an enhanced transformed phenotype and causes a robust stimulation of both ERK and the N-terminal c-Jun kinase (JNK). Microarray analysis reveals that the expression of the gene encoding SMOC-2 (secreted modular calcium-binding protein-2), which has been shown to synergize with different growth factors, is increased by at least 50-fold in cells stably expressing Ran(K152A) compared with cells expressing control vector. Knocking down SMOC-2 expression greatly reduces the ability of Ran(K152A) to stimulate anchorage-independent growth in NIH-3T3 cells and in SKBR3 cells and also inhibits cell invasion in fibroblasts. Collectively, our findings highlight a novel connection between the hyper-activation of the small GTPase Ran and the matricellular protein SMOC-2 that has important consequences for oncogenic transformation.
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Affiliation(s)
- Shawn K Milano
- Department of Molecular Medicine, Cornell University, Ithaca, New York 14853, USA
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Arainga M, Takeda E, Aida Y. Identification of bovine leukemia virus tax function associated with host cell transcription, signaling, stress response and immune response pathway by microarray-based gene expression analysis. BMC Genomics 2012; 13:121. [PMID: 22455445 PMCID: PMC3441221 DOI: 10.1186/1471-2164-13-121] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 03/16/2012] [Indexed: 12/21/2022] Open
Abstract
Background Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T-cell leukemia virus type I. The Tax protein of BLV is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. However, the effects of these mutations on functions other than transcriptional activation are unknown. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we used a large-scale host cell gene-profiling approach. Results Using a microarray containing approximately 18,400 human mRNA transcripts, we found several alterations after the expression of Tax proteins in genes involved in many cellular functions such as transcription, signal transduction, cell growth, apoptosis, stress response, and immune response, indicating that Tax protein has multiple biological effects on various cellular environments. We also found that TaxD247G strongly regulated more genes involved in transcription, signal transduction, and cell growth functions, contrary to TaxS240P, which regulated fewer genes. In addition, the expression of genes related to stress response significantly increased in the presence of TaxS240P as compared to wild-type Tax and TaxD247G. By contrast, the largest group of downregulated genes was related to immune response, and the majority of these genes belonged to the interferon family. However, no significant difference in the expression level of downregulated genes was observed among the Tax proteins. Finally, the expression of important cellular factors obtained from the human microarray results were validated at the RNA and protein levels by real-time quantitative reverse transcription-polymerase chain reaction and western blotting, respectively, after transfecting Tax proteins into bovine cells and human HeLa cells. Conclusion A comparative analysis of wild-type and mutant Tax proteins indicates that Tax protein exerts a significant impact on cellular functions as diverse as transcription, signal transduction, cell growth, stress response and immune response. Importantly, our study is the first report that shows the extent to which BLV Tax regulates the innate immune response.
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Affiliation(s)
- Mariluz Arainga
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Zhao Z, Wang J, Zhang X. Feedback regulation of Ran gene expression by Ran protein. Gene 2011; 485:85-90. [DOI: 10.1016/j.gene.2011.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 05/23/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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Zhou F, Zheng L, Yang Q, Qiu L, Huang J, Su T, Jiang S. Molecular analysis of a ras-like nuclear (Ran) gene from Penaeus monodon and its expression at the different ovarian stages of development. Mol Biol Rep 2011; 39:3821-7. [PMID: 21748319 DOI: 10.1007/s11033-011-1160-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 06/30/2011] [Indexed: 01/06/2023]
Abstract
In the present study, a ras-like nuclear (Ran) gene was obtained from the ovary and neurosecretory organ in eyestalk cDNA library of black tiger prawn (Penaeus monodon). The full-length black tiger prawn Ran (PmRan) cDNA consisted of 1140 nucleotides including an open reading frame (ORF) 648 bp, a 5' untranslated region (5'UTR) of 117 bp and a 3'UTR of 375 bp with a polyadenylation signal sequence "aataaa" and a poly (A) tail. The ORF encoded a peptide of 215 amino acids with molecular mass 24.6 kDa and a theoretical isoelectric point of 7.39. ScanProsite analysis indicated that PmRan protein sequence contained a small GTPase Ran family motif. Homology analysis of the deduced amino acid sequence of the PmRan with other known Ran sequences by MatGAT software revealed that the PmRan show very high homology with the sequences of other animals (92.1-98.6% similarity, 85.6-98.1% identity). Analysis of the tissue expression pattern of the PmRan gene showed that the PmRan mRNA was expressed in all tested tissues, including hepatopancreas, ovary, muscle, intestine, neurosecretory organ in eyestalk, neurosecretory organ in brain, stomach, and heart, with the highest levels in ovary. Furthermore, the PmRan expression was found to be high level in the six ovarian stages of development. The results indicated PmRan might play an important role in ovarian development.
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Affiliation(s)
- Falin Zhou
- South China Sea Fisheries Research Institute, CAFS, 231 Xingang Road Western, Guangzhou, 510300, Guangdong, China
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Gkiafi Z, Panayotou G. Comparative Proteomic Analysis Implicates COMMD Proteins as Epstein–Barr Virus Targets in the BL41 Burkitt’s Lymphoma Cell Line. J Proteome Res 2011; 10:2959-68. [DOI: 10.1021/pr100793m] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Zacharati Gkiafi
- Institute of Molecular Oncology, Biomedical Sciences Research Center “Alexander Fleming”, Vari, Greece
| | - George Panayotou
- Institute of Molecular Oncology, Biomedical Sciences Research Center “Alexander Fleming”, Vari, Greece
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The defective nuclear lamina in Hutchinson-gilford progeria syndrome disrupts the nucleocytoplasmic Ran gradient and inhibits nuclear localization of Ubc9. Mol Cell Biol 2011; 31:3378-95. [PMID: 21670151 DOI: 10.1128/mcb.05087-11] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mutant form of lamin A responsible for the premature aging disease Hutchinson-Gilford progeria syndrome (termed progerin) acts as a dominant negative protein that changes the structure of the nuclear lamina. How the perturbation of the nuclear lamina in progeria is transduced into cellular changes is undefined. Using patient fibroblasts and a variety of cell-based assays, we determined that progerin expression in Hutchinson-Gilford progeria syndrome inhibits the nucleocytoplasmic transport of several factors with key roles in nuclear function. We found that progerin reduces the nuclear/cytoplasmic concentration of the Ran GTPase and inhibits the nuclear localization of Ubc9, the sole E2 for SUMOylation, and of TPR, the nucleoporin that forms the basket on the nuclear side of the nuclear pore complex. Forcing the nuclear localization of Ubc9 in progerin-expressing cells rescues the Ran gradient and TPR import, indicating that these pathways are linked. Reducing nuclear SUMOylation decreases the nuclear mobility of the Ran nucleotide exchange factor RCC1 in vivo, and the addition of SUMO E1 and E2 promotes the dissociation of RCC1 and Ran from chromatin in vitro. Our data suggest that the cellular effects of progerin are transduced, at least in part, through reduced function of the Ran GTPase and SUMOylation pathways.
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HEYLAND ANDREAS, VUE ZER, VOOLSTRA CHRISTIANR, MEDINA MÓNICA, MOROZ LEONIDL. Developmental transcriptome of Aplysia californica. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART B, MOLECULAR AND DEVELOPMENTAL EVOLUTION 2011; 316B:113-34. [PMID: 21328528 PMCID: PMC4028319 DOI: 10.1002/jez.b.21383] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 09/08/2010] [Accepted: 10/12/2010] [Indexed: 11/08/2022]
Abstract
Genome-wide transcriptional changes in development provide important insight into mechanisms underlying growth, differentiation, and patterning. However, such large-scale developmental studies have been limited to a few representatives of Ecdysozoans and Chordates. Here, we characterize transcriptomes of embryonic, larval, and metamorphic development in the marine mollusc Aplysia californica and reveal novel molecular components associated with life history transitions. Specifically, we identify more than 20 signal peptides, putative hormones, and transcription factors in association with early development and metamorphic stages-many of which seem to be evolutionarily conserved elements of signal transduction pathways. We also characterize genes related to biomineralization-a critical process of molluscan development. In summary, our experiment provides the first large-scale survey of gene expression in mollusc development, and complements previous studies on the regulatory mechanisms underlying body plan patterning and the formation of larval and juvenile structures. This study serves as a resource for further functional annotation of transcripts and genes in Aplysia, specifically and molluscs in general. A comparison of the Aplysia developmental transcriptome with similar studies in the zebra fish Danio rerio, the fruit fly Drosophila melanogaster, the nematode Caenorhabditis elegans, and other studies on molluscs suggests an overall highly divergent pattern of gene regulatory mechanisms that are likely a consequence of the different developmental modes of these organisms.
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Affiliation(s)
| | - ZER VUE
- University of California, Merced, School of Natural Sciences, Merced, California
| | - CHRISTIAN R. VOOLSTRA
- University of California, Merced, School of Natural Sciences, Merced, California
- Red Sea Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - MÓNICA MEDINA
- University of California, Merced, School of Natural Sciences, Merced, California
| | - LEONID L. MOROZ
- The Whitney Laboratory for Marine Bioscience, University of Florida, Florida
- Department of Neuroscience, University of Florida, Florida
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Abstract
Roles of the GTPase Ran in cell life and division rely on a largely conserved mechanism, i.e. Ran's ability to interact with transport vectors. Modes of control of downstream factors, however, are diversified at particular times of the cell cycle. Specificity and fine-tuning emerge most clearly during mitosis. In the present article, we focus on the distinction between global mitotic control by the chromosomal Ran gradient and specific spatial and temporal control operated by localized Ran network members at sites of the mitotic apparatus in human cells.
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Pham DNT, Luo H, Wu J. Reduced Ran expression in Ran(+/-) fibroblasts increases cytokine-stimulated nuclear abundance of the AP-1 subunits c-Fos and c-Jun. FEBS Lett 2010; 584:4623-6. [PMID: 20965183 DOI: 10.1016/j.febslet.2010.10.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 10/05/2010] [Accepted: 10/14/2010] [Indexed: 11/24/2022]
Abstract
Ran (Ras-related nuclear protein), a Ras family GTPase, is involved in multiple cellular functions, including the regulation of DNA replication, cell cycle progression, nuclear structure formation, RNA processing-exportation, and nuclear protein importation. Ran(+/-) embryonic stem (ES) cells were produced in an attempt to generate Ran null mutant mice. Even after an extremely large number of blastocyst injections, no Ran(+/-) chimeric mice could be generated. Ran(+/-) ES cell-derived fibroblasts showed reduced Ran protein expression, and manifested augmented nuclear abundance of AP-1 factors (c-Jun and c-Fos) upon cytokine stimulation. Our experiments demonstrated that intracellular Ran protein levels controlled the nuclear presence of certain transcription factors, such as c-Fos and c-Jun.
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Affiliation(s)
- Diep Ngoc Thi Pham
- Laboratory of Immunology, Centre hospitalier de l'Université de Montréal (CRCHUM)-Hôpital Notre-Dame, Montreal, Quebec, Canada
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Zang A, Xu X, Neill S, Cai W. Overexpression of OsRAN2 in rice and Arabidopsis renders transgenic plants hypersensitive to salinity and osmotic stress. JOURNAL OF EXPERIMENTAL BOTANY 2010; 61:777-89. [PMID: 20018899 PMCID: PMC2814108 DOI: 10.1093/jxb/erp341] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 10/28/2009] [Accepted: 11/03/2009] [Indexed: 05/18/2023]
Abstract
Nucleo-cytoplasmic partitioning of regulatory proteins is increasingly being recognized as a major control mechanism for the regulation of signalling in plants. Ras-related nuclear protein (Ran) GTPase is required for regulating transport of proteins and RNA across the nuclear envelope and also has roles in mitotic spindle assembly and nuclear envelope (NE) assembly. However, thus far little is known of any Ran functions in the signalling pathways in plants in response to changing environmental stimuli. The OsRAN2 gene, which has high homology (77% at the amino acid level) with its human counterpart, was isolated here. Subcellular localization results showed that OsRan2 is mainly localized in the nucleus, with some in the cytoplasm. Transcription of OsRAN2 was reduced by salt, osmotic, and exogenous abscisic acid (ABA) treatments, as determined by real-time PCR. Overexpression of OsRAN2 in rice resulted in enhanced sensitivity to salinity, osmotic stress, and ABA. Seedlings of transgenic Arabidopsis thaliana plants overexpressing OsRAN2 were overly sensitive to salinity stress and exogenous ABA treatment. Furthermore, three ABA- or stress-responsive genes, AtNCED3, AtPLC1, and AtMYB2, encoding a key enzyme in ABA synthesis, a phospholipase C homologue, and a putative transcriptional factor, respectively, were shown to have differentially induced expression under salinity and ABA treatments in transgenic and wild-type Arabidopsis plants. OsRAN2 overexpression in tobacco epidermal leaf cells disturbed the nuclear import of a maize (Zea mays L.) leaf colour transcription factor (Lc). In addition, gene-silenced rice plants generated via RNA interference (RNAi) displayed pleiotropic developmental abnormalities and were male sterile.
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Affiliation(s)
- Aiping Zang
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
| | - Xiaojie Xu
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
| | - Steven Neill
- Centre for Research in Plant Science, University of the West of England, Bristol BS16 1QY, UK
| | - Weiming Cai
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Graduate School of Chinese Academy of Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China
- To whom correspondence should be addressed: E-mail:
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Spatial distribution and mobility of the Ran GTPase in live interphase cells. Biophys J 2010; 97:2164-78. [PMID: 19843449 DOI: 10.1016/j.bpj.2009.07.055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Revised: 07/14/2009] [Accepted: 07/30/2009] [Indexed: 12/30/2022] Open
Abstract
The GTPase Ran is a key regulator of molecular transport through nuclear pore complex (NPC) channels. To analyze the role of Ran in its nuclear transport function, we used several quantitative fluorescence techniques to follow the distribution and dynamics of an enhanced yellow fluorescent protein (EYFP)-Ran in HeLa cells. The diffusion coefficient of the majority of EYFP-Ran molecules throughout the cells corresponded to an unbound state, revealing the remarkably dynamic Ran regulation. Although we observed no significant immobile Ran populations in cells, approximately 10% of the cytoplasmic EYFP-Ran and 30% of the nuclear EYFP-Ran exhibited low mobility indicative of molecular interactions. The high fraction of slow nuclear EYFP-Ran reflects the expected numerous interactions of nuclear RanGTP with nuclear transport receptors. However, it is not high enough to support retention mechanisms as the main cause for the observed nuclear accumulation of Ran. The highest cellular concentration of EYFP-Ran was detected at the nuclear envelope, corresponding to approximately 200 endogenous Ran molecules for each NPC, and exceeding the currently estimated NPC channel transport capacity. Together with the relatively long residence time of EYFP-Ran at the nuclear envelope (33 +/- 14 ms), these observations suggest that only a fraction of the Ran concentrated at NPCs transits through NPC channels.
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Qiao X, Pham DNT, Luo H, Wu J. Ran overexpression leads to diminished T cell responses and selectively modulates nuclear levels of c-Jun and c-Fos. J Biol Chem 2009; 285:5488-96. [PMID: 20028981 DOI: 10.1074/jbc.m109.058024] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ras-related nuclear protein (Ran) is a Ras family GTPase, and its documented functions are the regulation of DNA replication, cell cycle progression, nuclear structure formation, RNA processing and exportation, and nuclear protein importation. In this study, we performed detailed mapping of Ran expression during mouse ontogeny using in situ hybridization. High Ran expression was found in various organs and tissues including the thymus cortex and spleen white pulp. Ran was induced in T cells 24 h after their activation. The function of Ran in the immune system was investigated using Ran transgenic (Tg) mice. In Ran Tg T cells, there was compromised activation marker expression, lymphokine secretion, and proliferation upon T cell receptor activation in vitro when compared with wild type T cells. Tg mice also manifested defective delayed type hypersensitivity in vivo. Upon PMA and ionomycin stimulation, Tg T cells were defective in nuclear accumulation of AP-1 factors (c-Jun and c-Fos) but not NF-kappaB family members. Our experiments showed that Ran had important regulatory function in T cell activation. One of the possible mechanisms is that intracellular Ran protein levels control the nuclear retention for selective transcription factors such as c-Jun and c-Fos of AP-1, which is known to be critical in T cell activation and proliferation and lymphokine secretion.
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Affiliation(s)
- Xiaoying Qiao
- Laboratory of Immunology, Centre de Recherche, Centre Hospitalier de l'Université de Montréal, Montreal, Quebec H2L 4M1, Canada
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Leishmania donovani Ran-GTPase interacts at the nuclear rim with linker histone H1. Biochem J 2009; 424:367-74. [DOI: 10.1042/bj20090576] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ran-GTPase regulates multiple cellular processes such as nucleocytoplasmic transport, mitotic spindle assembly, nuclear envelope assembly, cell-cycle progression and the mitotic checkpoint. The leishmanial Ran protein, in contrast with its mammalian counterpart which is predominately nucleoplasmic, is localized at the nuclear rim. The aim of the present study was to characterize the LdRan (Leishmania donovani Ran) orthologue with an emphasis on the Ran–histone association. LdRan was found to be developmentally regulated, expressed 3-fold less in the amastigote stage. LdRan overexpression caused a growth defect linked to a delayed S-phase progression in promastigotes as for its mammalian counterpart. We report for the first time that Ran interacts with a linker histone, histone H1, in vitro and that the two proteins co-localize at the parasite nuclear rim. Interaction of Ran with core histones H3 and H4, creating in metazoans a chromosomal Ran-GTP gradient important for mitotic spindle assembly, is speculative in Leishmania spp., not only because this parasite undergoes a closed mitosis, but also because the main localization of LdRan is different from that of core histone H3. Interaction of Ran with the leishmanial linker histone H1 (LeishH1) suggests that this association maybe involved in modulation of pathways other than those documented for the metazoan Ran–core histone association.
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38
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Differential gene expression profiling in the developed ovaries between the parthenogenetic and bisexual female rice water weevils, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae). ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11434-009-0537-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Lui K, Huang Y. RanGTPase: A Key Regulator of Nucleocytoplasmic Trafficking. MOLECULAR AND CELLULAR PHARMACOLOGY 2009; 1:148-156. [PMID: 20300488 PMCID: PMC2839366 DOI: 10.4255/mcpharmacol.09.19] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
RanGTPase belongs to the Ras superfamily of small GTPases. It possesses a distinctive acidic C-terminal DEDDDL motif and predominantly localizes to the nucleus. RanGTPase is known to regulate nucleocytoplasmic trafficking as well as mitotic spindle and nuclear envelope formation. Ran-directed nucleocytoplasmic trafficking is an energy-dependent directional process that also depends on nuclear import or export signals. Ran-directed nucleocytoplasmic trafficking is also facilitated by several cellular components, including RanGTPase, karyopherins, NTF2 and nucleoporins. GTP-bound Ran is asymmetrically distributed in the nucleus, while GDP-bound Ran is predominantly cytoplasmic. Controlled by RanGEF and RanGAP, RanGTPase cycles between the GDP- and GTP-bound states enabling it to shuttle cargoes in an accurate spatial and temporal manner. RanGTPase plays a role in the nuclear import in such a way that GTP-bound Ran dissociates importin:cargo complex in the nucleus and recycles importin back to cytoplasm. Likewise, RanGTPase plays a role in the nuclear export in such a way that nuclear GTP-bound Ran triggers the aggregation of Ran:exportin:cargo trimeric complex which is then transported to cytoplasm while hydrolysis of RanGTP to RanGDP releases the export cargoes in cytoplasm. RanGTPase has been reported to be essential for cell viability and its over-expression is linked to tumorigenesis. Thus, RanGTPase plays a crucial role in regulating key cellular events and alterations in its expression may lead to cancer development and/or progression.
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Affiliation(s)
- Ki Lui
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, New York
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40
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Frankel MB, Knoll LJ. Functional analysis of key nuclear trafficking components reveals an atypical Ran network required for parasite pathogenesis. Mol Microbiol 2008; 70:410-20. [PMID: 18761691 DOI: 10.1111/j.1365-2958.2008.06419.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Protozoan parasites represent major public health challenges. Many aspects of their cell biology are distinct from their animal hosts, providing potential therapeutic targets. Toxoplasma gondii is a protozoan parasite that contains a divergent regulator of chromosome condensation 1 (TgRCC1) that is required for virulence and efficient nuclear trafficking. RCC1 proteins function as a guanine exchange factor for Ras-related nuclear protein (Ran), an abundant GTPase responsible for the majority of nucleocytoplasmic transport. Here we show that while there are dramatic differences from well-conserved RCC1 proteins, TgRCC1 associates with chromatin, interacts with Ran and complements a mammalian temperature-sensitive RCC1 mutant cell line. During the investigation of TgRCC1, we observed several unprecedented phenotypes for TgRan, despite a high level of sequence conservation. The cellular distribution of TgRan is found throughout the parasite cell, whereas Ran in late branching eukaryotes is predominantly nuclear. Additionally, T. gondii tolerates at least low-level expression of dominant lethal Ran mutants. Wild type parasites expressing dominant negative TgRan grew similarly to wild type in standard tissue culture conditions, but were attenuated in serum-starved host cells and mice. These growth characteristics paralleled the TgRCC1 mutant and highlight the importance of the nuclear transport pathway for virulence of eukaryotic pathogens.
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Affiliation(s)
- Matthew B Frankel
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, 1300 University Avenue, Madison, WI 53706, USA
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41
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Kelley JB, Paschal BM. Hyperosmotic stress signaling to the nucleus disrupts the Ran gradient and the production of RanGTP. Mol Biol Cell 2007; 18:4365-76. [PMID: 17761537 PMCID: PMC2043571 DOI: 10.1091/mbc.e07-01-0089] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The RanGTP gradient depends on nucleocytoplasmic shuttling of Ran and its nucleotide exchange in the nucleus. Here we show that hyperosmotic stress signaling induced by sorbitol disrupts the Ran protein gradient and reduces the production of RanGTP. Ran gradient disruption is rapid and is followed by early (10-20 min) and late (30-60 min) phases of recovery. Results from SB203580 and siRNA experiments suggest the stress kinase p38 is important for Ran gradient recovery. NTF2 and Mog1, which are transport factors that regulate the nuclear localization of Ran, showed kinetics of delocalization and recovery similar to Ran. Microinjection of a nuclear localization signal reporter protein revealed that sorbitol stress decreases the rate of nuclear import. Sorbitol stress also slowed RCC1 mobility in the nucleus, which is predicted to reduce RCC1 dissociation from chromatin and RanGTP production. This was tested using a FRET biosensor that registers nuclear RanGTP levels, which were reduced in response to sorbitol stress. Although sorbitol alters nucleotide levels, we show that inverting the GTP/GDP ratio in cells is not sufficient to disrupt the Ran gradient. Thus, the Ran system is a target of hyperosmotic stress signaling, and cells use protein localization-based mechanisms as part of a rapid stress response.
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Affiliation(s)
- Joshua B. Kelley
- Center for Cell Signaling, Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908
| | - Bryce M. Paschal
- Center for Cell Signaling, Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908
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42
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Ma L, Hong Z, Zhang Z. Perinuclear and nuclear envelope localizations of Arabidopsis Ran proteins. PLANT CELL REPORTS 2007; 26:1373-82. [PMID: 17530257 DOI: 10.1007/s00299-007-0367-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 04/19/2007] [Indexed: 05/15/2023]
Abstract
Using phragmoplastin-interacting protein 1 (PhrIP1) as bait, we isolated an Arabidopsis cDNA encoding Ran2, a small Ras-like GTP-binding protein. The interaction between PhrIP1 and Ran2 was confirmed by an in vitro protein-protein interaction assay with purified Ran2 and PhrIP1. The plant Ran2 shares high sequence homology, 78 and 86% at the amino acid level, with human Ran/TC4 and C. elegans Ran, respectively. Our results obtained from enzyme assays and Western blot analysis show that Ran2 has intrinsic GTPase activity and is present in the soluble fraction of Arabidopsis seedling extract. Fluorescent microscopy using anti-Ran2 antibody revealed that the Ran protein is localized in the perinuclear region with the highest concentration at the nuclear envelope. In contrast to its animal counterparts that are present in the nucleoplasm, the Ran protein is absent inside the nucleus. These results suggest that plant Ran proteins may be involved in mediation of nucleocytoplasmic transport and assembly of the nuclear envelope after karyokinesis in plant cells.
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Affiliation(s)
- Lian Ma
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
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43
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Silljé HHW, Nagel S, Körner R, Nigg EA. HURP is a Ran-importin beta-regulated protein that stabilizes kinetochore microtubules in the vicinity of chromosomes. Curr Biol 2006; 16:731-42. [PMID: 16631580 DOI: 10.1016/j.cub.2006.02.070] [Citation(s) in RCA: 208] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 01/31/2006] [Accepted: 02/28/2006] [Indexed: 12/30/2022]
Abstract
BACKGROUND Formation of a bipolar mitotic spindle in somatic cells requires the cooperation of two assembly pathways, one based on kinetochore capture by centrosomal microtubules, the other on RanGTP-mediated microtubule organization in the vicinity of chromosomes. How RanGTP regulates kinetochore-microtubule (K-fiber) formation is not presently understood. RESULTS Here we identify the mitotic spindle protein HURP as a novel target of RanGTP. We show that HURP is a direct cargo of importin beta and that in interphase cells, it shuttles between cytoplasm and nucleus. During mitosis, HURP localizes predominantly to kinetochore microtubules in the vicinity of chromosomes. Overexpression of importin beta or RanT24N (resulting in low RanGTP) negatively regulates its spindle localization, whereas overexpression of RanQ69L (mimicking high RanGTP) enhances HURP association with the spindle. Thus, RanGTP levels control HURP localization to the mitotic spindle in vivo, a conclusion supported by the analysis of tsBN2 cells (mutant in RCC1). Upon depletion of HURP, K-fiber stabilization is impaired and chromosome congression is delayed. Nevertheless, cells eventually align their chromosomes, progress into anaphase, and exit mitosis. HURP is able to bundle microtubules and, in vitro, this function is abolished upon complex formation with importin beta and regulated by Ran. These data indicate that HURP stabilizes K-fibers by virtue of its ability to bind and bundle microtubules. CONCLUSIONS Our study identifies HURP as a novel component of the Ran-importin beta-regulated spindle assembly pathway, supporting the conclusion that K-fiber formation and stabilization involves both the centrosome-dependent microtubule search and capture mechanism and the RanGTP pathway.
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Affiliation(s)
- Herman H W Silljé
- Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
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44
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Bapteste E, Charlebois RL, MacLeod D, Brochier C. The two tempos of nuclear pore complex evolution: highly adapting proteins in an ancient frozen structure. Genome Biol 2005; 6:R85. [PMID: 16207356 PMCID: PMC1257468 DOI: 10.1186/gb-2005-6-10-r85] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Revised: 07/15/2005] [Accepted: 09/01/2005] [Indexed: 11/24/2022] Open
Abstract
An analysis of the taxonomic distribution, evolutionary rates and phylogenies of 65 proteins related to the nuclear pore complex shows high heterogeneity of evolutionary rates between these proteins. Background The origin of the nuclear compartment has been extensively debated, leading to several alternative views on the evolution of the eukaryotic nucleus. Until recently, too little phylogenetic information was available to address this issue by using multiple characters for many lineages. Results We analyzed 65 proteins integral to or associated with the nuclear pore complex (NPC), including all the identified nucleoporins, the components of their anchoring system and some of their main partners. We used reconstruction of ancestral sequences of these proteins to expand the detection of homologs, and showed that the majority of them, present all over the nuclear pore structure, share homologs in all extant eukaryotic lineages. The anchoring system, by contrast, is analogous between the different eukaryotic lineages and is thus a relatively recent innovation. We also showed the existence of high heterogeneity of evolutionary rates between these proteins, as well as between and within lineages. We show that the ubiquitous genes of the nuclear pore structure are not strongly conserved at the sequence level, and that only their domains are relatively well preserved. Conclusion We propose that an NPC very similar to the extant one was already present in at least the last common ancestor of all extant eukaryotes and it would not have undergone major changes since its early origin. Importantly, we observe that sequences and structures obey two very different tempos of evolution. We suggest that, despite strong constraints that froze the structural evolution of the nuclear pore, the NPC is still highly adaptive, modern, and flexible at the sequence level.
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Affiliation(s)
- Eric Bapteste
- Canadian Institute for Advanced Research Program in Evolutionary Biology, Department of Biochemistry and Molecular Biology, Dalhousie University, College Street, Halifax, Nova Scotia, B3H 1X5 Canada
| | - Robert L Charlebois
- Canadian Institute for Advanced Research Program in Evolutionary Biology, Department of Biochemistry and Molecular Biology, Dalhousie University, College Street, Halifax, Nova Scotia, B3H 1X5 Canada
- Genome Atlantic, Department of Biochemistry and Molecular Biology, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, B3H 1X5, Canada
| | - Dave MacLeod
- Canadian Institute for Advanced Research Program in Evolutionary Biology, Department of Biochemistry and Molecular Biology, Dalhousie University, College Street, Halifax, Nova Scotia, B3H 1X5 Canada
| | - Céline Brochier
- EA EGEE (Evolution, Génome, Environnement), Centre Saint-Charles, Université Aix-Marseille I, place Victor Hugo, 13331 Marseille Cedex 3, France
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Quimby BB, Arnaoutov A, Dasso M. Ran GTPase regulates Mad2 localization to the nuclear pore complex. EUKARYOTIC CELL 2005; 4:274-80. [PMID: 15701789 PMCID: PMC549331 DOI: 10.1128/ec.4.2.274-280.2005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In yeast and mammalian cells, the spindle assembly checkpoint proteins Mad1p and Mad2p localize to the nuclear pore complex (NPC) during interphase. Deletion of MAD1 or MAD2 did not affect steady-state nucleocytoplasmic distribution of a classical nuclear localization signal-containing reporter, a nuclear export signal-containing reporter, or Ran localization. We utilized cells with conditional mutations in the yeast Ran GTPase pathway to examine the relationship between Ran and targeting of checkpoint regulators to the NPC. Mutations that disrupt the concentration of Ran in the nucleus displaced Mad2p but not Mad1p from the NPC. The displacement of Mad2p in M-phase cells was correlated with activation of the spindle checkpoint. Our observations demonstrate that Mad2p localization at NPCs is sensitive to nuclear levels of Ran and suggest that release of Mad2p from NPCs is closely linked with spindle assembly checkpoint activation in yeast. This is the first evidence indicating that Ran affects the localization of Mad2p to the NPC.
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Affiliation(s)
- B Booth Quimby
- Laboratory of Gene Regulation and Development, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-5431, USA.
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46
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Abstract
It has been nearly 20 years since the discovery of the first component of the Ran-GTPase pathway. Since then, nearly 100 articles, more than half of which have been published in the past three years, have reported the identification of additional components of the system and the existence of their structural and functional homologues in organisms ranging from yeast to man. The Ran system affects a vast array of nuclear processes including RNA metabolism, DNA replication, chromosome condensation and decondensation, and nucleocytoplasmic transport of protein and RNA. The current challenge is to identify the molecular targets that link the Ran-GTPase system to this collection o f nuclear processes.
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Affiliation(s)
- S Sazer
- Verna and Marrs McLean Dept of Biochemistry, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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47
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Ghobrial IM, McCormick DJ, Kaufmann SH, Leontovich AA, Loegering DA, Dai NT, Krajnik KL, Stenson MJ, Melhem MF, Novak AJ, Ansell SM, Witzig TE. Proteomic analysis of mantle-cell lymphoma by protein microarray. Blood 2005; 105:3722-30. [PMID: 15650054 PMCID: PMC1895014 DOI: 10.1182/blood-2004-10-3999] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mantle-cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma (NHL) that behaves aggressively and remains incurable. In order to understand the pathogenesis of MCL and design new therapies, it is important to accurately analyze molecular changes in pathways dysregulated in MCL. We used antibody microarrays to compare patterns of protein expression between CD19(+) purified B lymphocytes from normal tonsil and 7 cases of histologically confirmed MCL. Protein overexpression was defined as a higher than 1.3-fold or 2-fold increase in at least 67% of tumor samples compared with normal B-cell control. Of the polypeptides, 77 were overexpressed using the higher than 1.3-fold cutoff, and 13 were overexpressed using the 2-fold cutoff. These included cell cycle regulators (regulator of chromosome condensation 1 [RCC1], murine double minute 2 [MDM2]), a kinase (citron Rho-interacting kinase [CRIK]), chaperone proteins (heat shock 90-kDa protein [Hsp90], Hsp10), and phosphatase regulators (A-kinase anchor protein 1 [AKAP149], protein phosphatase 5 [PP5], and inhibitor 2). The elevated expression of some of these polypeptides was confirmed by immunoblotting and immunohistochemistry, whereas elevated expression of others could not be confirmed, illustrating the importance of confirmatory studies. This study describes a novel technique that identifies proteins dysregulated in MCL.
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Affiliation(s)
- Irene M Ghobrial
- Division of Hematology, Department of Internal Medicine, Mayo Clinic, Rochester, MN 55905, USA
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Zhao J, Jin SB, Wieslander L. CRM1 and Ran are present but a NES-CRM1-RanGTP complex is not required in Balbiani ring mRNP particles from the gene to the cytoplasm. J Cell Sci 2004; 117:1553-66. [PMID: 15020682 DOI: 10.1242/jcs.00992] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Messenger RNA is formed from precursors known as pre-mRNA. These precursors associate with proteins to form pre-mRNA-protein (pre-mRNP) complexes. Processing machines cap, splice and polyadenylate the pre-mRNP and in this way build the mRNP. These processing machines also affect the export of the mRNP complexes from the nucleus to the cytoplasm. Export to the cytoplasm takes place through a structure in the nuclear membrane called the nuclear pore complex (NPC). Export involves adapter proteins in the mRNP and receptor proteins that bind to the adapter proteins and to components of the NPC. We show that the export receptor chromosomal region maintenance protein 1 (CRM1), belonging to a family of proteins known as importin-beta-like proteins, binds to gene-specific Balbiani ring (BR) pre-mRNP while transcription takes place. We also show that the GTPase known as Ran binds to BR pre-mRNP, and that it binds mainly in the interchromatin. However, we also show using leptomycin B treatment that a NES-CRM1-RanGTP complex is not essential for export, even though both CRM1 and Ran accompany the BR mRNP through the NPC. Our results therefore suggest that several export receptors associate with BR mRNP and that these receptors have redundant functions in the nuclear export of BR mRNP.
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Affiliation(s)
- Jian Zhao
- Department of Molecular Biology and Functional Genomics, Stockholm University, SE-106 91 Stockholm, Sweden
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Cushman I, Stenoien D, Moore MS. The dynamic association of RCC1 with chromatin is modulated by Ran-dependent nuclear transport. Mol Biol Cell 2003; 15:245-55. [PMID: 14565978 PMCID: PMC307544 DOI: 10.1091/mbc.e03-06-0409] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Regulator of chromosome condensation (RCC1) binding to chromatin is highly dynamic, as determined by fluorescence recovery after photobleaching analysis of GFP-RCC1 in stably transfected tsBN2 cells. Microinjection of wild-type or Q69L Ran markedly slowed the mobility of GFP-RCC1, whereas T24N Ran (defective in nucleotide loading) decreased it further still. We found significant alterations in the mobility of intranuclear GFP-RCC1 after treatment with agents that disrupt different Ran-dependent nuclear export pathways. Leptomycin B, which inhibits Crm1/RanGTP-dependent nuclear export, significantly increased the mobility of RCC1 as did high levels of actinomycin D (to inhibit RNA polymerases I, II, and III) or alpha-amanitin (to inhibit RNA polymerases II and III) as well as energy depletion. Inhibition of just mRNA transcription, however, had no affect on GFP-RCC1 mobility consistent with mRNA export being a Ran-independent process. In permeabilized cells, cytosol and GTP were required for the efficient release of GFP-RCC1 from chromatin. Recombinant Ran would not substitute for cytosol, and high levels of supplemental Ran inhibited the cytosol-stimulated release. Thus, RCC1 release from chromatin in vitro requires a factor(s) distinct from, or in addition to, Ran and seems linked in vivo to the availability of Ran-dependent transport cargo.
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Affiliation(s)
- Ian Cushman
- Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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Nagata T, Takahashi Y, Ishii Y, Asai S, Nishida Y, Murata A, Koshinaga T, Fukuzawa M, Hamazaki M, Asami K, Ito E, Ikeda H, Takamatsu H, Koike K, Kikuta A, Kuroiwa M, Watanabe A, Kosaka Y, Fujita H, Miyake M, Mugishima H. Transcriptional profiling in hepatoblastomas using high-density oligonucleotide DNA array. CANCER GENETICS AND CYTOGENETICS 2003; 145:152-60. [PMID: 12935928 DOI: 10.1016/s0165-4608(03)00065-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Hepatoblastoma is a common hepatic tumor in children. Although evidence regarding cytogenetic and molecular genetic alterations in hepatoblastomas has been reported, the molecular events affecting the biologic characteristics of this tumor, including alterations of the gene expression profile, are largely unknown. To identify genes differentially expressed between nondiseased liver (NDL) and hepatoblastoma tumor (HBT), we analyzed the gene expression profile in 14 NDL and 16 HBT samples using a high-density oligonucleotide DNA array. Using Mann-Whitney U test followed by the k-nearest neighbor algorithm, we identified 26 genes (predictor genes) that were able to assign unknown samples derived from NDL and HBT to either the NDL group or HBT group with 100% accuracy. Using a cross-validation approach, we confirmed that the k-nearest neighbor algorithm assigned the particular samples derived from NDL and HBT to either the NDL or HBT group with 93.3% (28/30 samples) accuracy. In the 26 predictor genes, we found alteration of the expression of genes regulating cell division (NAP1L1, STMN1, CCNG2, and CDC7L1) and tumor cell growth (IGF2 and IGFBP4) in HBT. Four predictor genes (ETV3, TPR, CD34, and NR1I3) were also found to be mapped to the chromosomal region 1q21 approximately q32, which has been reported to be frequently involved in the development of hepatoblastoma. The findings obtained in this study suggest that alteration of the expression of some genes regulating cell division and tumor cell growth may be characteristics of the gene expression profile in HBT, and that alteration of the expression of the four predictor genes mapped to chromosomal region 1q21 approximately q32 may also contribute to the differences in gene expression profile between NDL and HBT.
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Affiliation(s)
- Toshihito Nagata
- Department of Advanced Medicine, Nihon University, School of Medicine, 30-1 Oyaguchikami-cho, Itabashi-ku, Tokyo 173-8610, Japan.
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