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Kleissl L, Weinmüllner R, Lämmermann I, Dingelmaier-Hovorka R, Jafarmadar M, El Ghalbzouri A, Stary G, Grillari J, Dellago H. PRPF19 modulates morphology and growth behavior in a cell culture model of human skin. FRONTIERS IN AGING 2023; 4:1154005. [PMID: 37214773 PMCID: PMC10196211 DOI: 10.3389/fragi.2023.1154005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 04/11/2023] [Indexed: 05/24/2023]
Abstract
The skin provides one of the most visual aging transformations in humans, and premature aging as a consequence of oxidative stress and DNA damage is a frequently seen effect. Cells of the human skin are continuously exposed to endogenous and exogenous DNA damaging factors, which can cause DNA damage in all phases of the cell cycle. Increased levels of DNA damage and/or defective DNA repair can, therefore, accelerate the aging process and/or lead to age-related diseases like cancer. It is not yet clear if enhanced activity of DNA repair factors could increase the life or health span of human skin cells. In previous studies, we identified and characterized the human senescence evasion factor (SNEV)/pre-mRNA-processing factor (PRPF) 19 as a multitalented protein involved in mRNA splicing, DNA repair pathways and lifespan regulation. Here, we show that overexpression of PRPF19 in human dermal fibroblasts leads to a morphological change, reminiscent of juvenile, papillary fibroblasts, despite simultaneous expression of senescence markers. Moreover, conditioned media of this subpopulation showed a positive effect on keratinocyte repopulation of wounded areas. Taken together, these findings indicate that PRPF19 promotes cell viability and slows down the aging process in human skin.
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Affiliation(s)
- Lisa Kleissl
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Regina Weinmüllner
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
- Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria
| | - Ingo Lämmermann
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
- Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria
| | | | - Mohammad Jafarmadar
- Ludwig Boltzmann Institute for Traumatology in cooperation with AUVA, Vienna, Austria
| | | | - Georg Stary
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
- Department of Dermatology, Medical University of Vienna, Vienna, Austria
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Johannes Grillari
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
- Ludwig Boltzmann Institute for Traumatology in cooperation with AUVA, Vienna, Austria
| | - Hanna Dellago
- Institute of Molecular Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
- Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria
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2
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Harries LW. Dysregulated RNA processing and metabolism: a new hallmark of ageing and provocation for cellular senescence. FEBS J 2023; 290:1221-1234. [PMID: 35460337 DOI: 10.1111/febs.16462] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/28/2022] [Accepted: 04/21/2022] [Indexed: 12/23/2022]
Abstract
The human genome is capable of producing hundreds of thousands of different proteins and non-coding RNAs from <20 000 genes, in a co-ordinated and regulated fashion. This is achieved by a collection of phenomena known as mRNA processing and metabolism, and encompasses events in the life cycle of an RNA from synthesis to degradation. These factors are critical determinants of cellular adaptability and plasticity, which allows the cell to adjust its transcriptomic output in response to its internal and external environment. Evidence is building that dysfunctional RNA processing and metabolism may be a key contributor to the development of cellular senescence. Senescent cells by definition have exited cell cycle, but have gained functional features such as the secretion of the senescence-associated secretory phenotype (SASP), a known driver of chronic disease and perhaps even ageing itself. In this review, I will outline the impact of dysregulated mRNA processing and metabolism on senescence and ageing at the level of genes, cells and systems, and describe the mechanisms by which progressive deterioration in these processes may impact senescence and organismal ageing. Finally, I will present the evidence implicating this important process as a new hallmark of ageing, which could be harnessed in the future to develop new senotherapeutic interventions for chronic disease.
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3
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Prp19 Facilitated p21-Dependent Senescence of Hepatocellular Carcinoma Cells. JOURNAL OF ONCOLOGY 2022; 2022:5705896. [PMID: 35356253 PMCID: PMC8959953 DOI: 10.1155/2022/5705896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 01/19/2022] [Accepted: 02/24/2022] [Indexed: 12/24/2022]
Abstract
Introduction Evidence suggests that the role of senescence in the development of cancer is context-dependent. An orthologue of human pre-mRNA processing factor 19 (Prp19) attenuates the senescence of human endothelial cells. Prp19 has been reported to be involved in the progression of hepatocellular carcinoma (HCC). This work aims to investigate the effect of Prp19 on the senescence of HCC. Materials and Methods Senescence of L02 cells and HCC cells under different stimuli was detected through cell cycle analysis, SA-β-gal staining, and senescence associated secretory phenotype analysis. The relationship between Prp19 and senescence-related proteins was evaluated using real-time RT-PCR, western blot assay, and immunohistochemistry. Subcutaneous xenograft tumors in nude mice were used to evaluate the role of Prp19 on senescence in vivo. Data analysis was carried out using GraphPad Prism 6. Results Prp19 facilitated the senescence of L02 cells and HCC cells under different stresses. Prp19 positively modulated p21 expression in the mRNA level. Downregulation of Prp19 promoted the growth of subcutaneous xenograft tumors generated by HCC cell lines. Conclusions Prp19 may promote senescence of HCC cells via regulating p21 expression.
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Idrissou M, Maréchal A. The PRP19 Ubiquitin Ligase, Standing at the Cross-Roads of mRNA Processing and Genome Stability. Cancers (Basel) 2022; 14:cancers14040878. [PMID: 35205626 PMCID: PMC8869861 DOI: 10.3390/cancers14040878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 02/01/2022] [Accepted: 02/04/2022] [Indexed: 12/07/2022] Open
Abstract
mRNA processing factors are increasingly being recognized as important regulators of genome stability. By preventing and resolving RNA:DNA hybrids that form co-transcriptionally, these proteins help avoid replication-transcription conflicts and thus contribute to genome stability through their normal function in RNA maturation. Some of these factors also have direct roles in the activation of the DNA damage response and in DNA repair. One of the most intriguing cases is that of PRP19, an evolutionarily conserved essential E3 ubiquitin ligase that promotes mRNA splicing, but also participates directly in ATR activation, double-strand break resection and mitosis. Here, we review historical and recent work on PRP19 and its associated proteins, highlighting their multifarious cellular functions as central regulators of spliceosome activity, R-loop homeostasis, DNA damage signaling and repair and cell division. Finally, we discuss open questions that are bound to shed further light on the functions of PRP19-containing complexes in both normal and cancer cells.
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Affiliation(s)
- Mouhamed Idrissou
- Faculty of Sciences, Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada;
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC J1H 5N3, Canada
| | - Alexandre Maréchal
- Faculty of Sciences, Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada;
- Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC J1H 5N3, Canada
- Correspondence:
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5
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He Y, Huang C, Cai K, Liu P, Chen X, Xu YI, Ming Z, Liu Q, Xie Q, Xia X, Sun Y, Luo J, Wei R. PRPF19 promotes tongue cancer growth and chemoradiotherapy resistance. Acta Biochim Biophys Sin (Shanghai) 2021; 53:893-902. [PMID: 33954334 DOI: 10.1093/abbs/gmab059] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Indexed: 12/19/2022] Open
Abstract
Pre-mRNA processing factor 19 (PRPF19) is a multifaceted protein and participates in DNA damage response and pre-mRNA processing. The role of PRPF19 in cancer is unclear. Here, we report that the expression of PRPF19 in human tongue cancer is associated with unfavorable prognosis. Overexpression of PRPF19 promotes while knockdown of PRPF19 inhibits tongue cancer cell migration, proliferation, and tumor growth. Overexpression of PRPF19 increases the resistance of tongue cancer cells to radiation and cisplatin treatment. Furthermore, PRPF19 regulates the expression of solute carrier family 40 member 1 (SLC40A1) and mono-ADP ribosylhydrolase 2 (MACROD2), knockdown of SLC40A1 or MACROD2 decreases the sensitivity of tongue cancer cells to radiation and cisplatin treatment. Thus, our results establish a key role of PRPF19 in tongue cancer growth and chemoradiotherapy resistance, targeting PRPF19 would be an effective therapeutic strategy for tongue cancer, especially for those resistant to chemoradiotherapy.
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Affiliation(s)
- Yihong He
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Changhao Huang
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Kaimei Cai
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Pei Liu
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Xueyan Chen
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Y i Xu
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Zhengnan Ming
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Central South University, Changsha 410008, China
| | - Qingqing Liu
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Qiongxuan Xie
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Xue Xia
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Biochemistry and Molecular Biology, School of Life Sciences, Central South University, Changsha 410008, China
| | - Yangqing Sun
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Junli Luo
- Department of General Surgery and the Hunan Provincial Key Lab of Precision Diagnosis and Treatment for Gastrointestinal Tumor, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Rui Wei
- Department of Oncology, Xiangya Hospital, Central South University, Changsha 410008, China
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6
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Sucularli C, Thomas P, Kocak H, White JS, O'Connor BC, Keegan CE. High-throughput gene expression analysis identifies p53-dependent and -independent pathways contributing to the adrenocortical dysplasia (acd) phenotype. Gene 2018; 679:219-231. [PMID: 30189268 PMCID: PMC6186184 DOI: 10.1016/j.gene.2018.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 08/24/2018] [Accepted: 09/03/2018] [Indexed: 11/18/2022]
Abstract
In mammalian cells TPP1, encoded by the Acd gene, is a key component of the shelterin complex, which is required for telomere length maintenance and telomere protection. In mice, a hypomorphic mutation in Acd causes the adrenocortical dysplasia (acd) phenotype, which includes limb and body axis anomalies, and perinatal lethality. p53 deficiency partially rescues limb and body axis anomalies in acd mutant embryos, but not perinatal lethality, implicating p53-independent mechanisms in the acd phenotype. Loss of function of most shelterin proteins results in early embryonic lethality. Thus, study of the hypomorphic acd allele provides a unique opportunity to understand telomere dysfunction at an organismal level. The aim of this study was to identify transcriptome alterations in acd mutant and acd, p53 double mutant embryos to understand the p53-dependent and -independent factors that contribute to the mutant phenotypes in the context of the whole organism. Genes involved in developmental processes, cell cycle, metabolic pathways, tight junctions, axon guidance and signaling pathways were regulated by p53-driven mechanisms in acd mutant embryos, while genes functioning in immune response, and RNA processing were altered independently of p53 in acd, p53 double mutant embryos. To our best of knowledge, this is the first study revealing detailed transcriptomic alterations, reflecting novel p53-dependent and -independent pathways contributing to the acd phenotype. Our data confirm the importance of cell cycle and DNA repair pathways, and suggest novel links between telomere dysfunction and immune system regulation and the splicing machinery. Given the broad applicability of telomere maintenance in growth, development, and genome stability, our data will also provide a rich resource for others studying telomere maintenance and DNA damage responses in mammalian model systems.
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Affiliation(s)
- Ceren Sucularli
- Department of Bioinformatics, Institute of Health Sciences, Hacettepe University, 06100 Ankara, Turkey
| | - Peedikayil Thomas
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | - Hande Kocak
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; Department of Medical Biology and Genetics, Istanbul Bilim University, Istanbul, Turkey
| | - James S White
- Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
| | | | - Catherine E Keegan
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA; Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA.
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Yates M, Maréchal A. Ubiquitylation at the Fork: Making and Breaking Chains to Complete DNA Replication. Int J Mol Sci 2018; 19:E2909. [PMID: 30257459 PMCID: PMC6213728 DOI: 10.3390/ijms19102909] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 12/11/2022] Open
Abstract
The complete and accurate replication of the genome is a crucial aspect of cell proliferation that is often perturbed during oncogenesis. Replication stress arising from a variety of obstacles to replication fork progression and processivity is an important contributor to genome destabilization. Accordingly, cells mount a complex response to this stress that allows the stabilization and restart of stalled replication forks and enables the full duplication of the genetic material. This response articulates itself on three important platforms, Replication Protein A/RPA-coated single-stranded DNA, the DNA polymerase processivity clamp PCNA and the FANCD2/I Fanconi Anemia complex. On these platforms, the recruitment, activation and release of a variety of genome maintenance factors is regulated by post-translational modifications including mono- and poly-ubiquitylation. Here, we review recent insights into the control of replication fork stability and restart by the ubiquitin system during replication stress with a particular focus on human cells. We highlight the roles of E3 ubiquitin ligases, ubiquitin readers and deubiquitylases that provide the required flexibility at stalled forks to select the optimal restart pathways and rescue genome stability during stressful conditions.
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Affiliation(s)
- Maïlyn Yates
- Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
| | - Alexandre Maréchal
- Department of Biology, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
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8
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Programming of Cell Resistance to Genotoxic and Oxidative Stress. Biomedicines 2018; 6:biomedicines6010005. [PMID: 29301323 PMCID: PMC5874662 DOI: 10.3390/biomedicines6010005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2017] [Revised: 12/23/2017] [Accepted: 12/31/2017] [Indexed: 12/23/2022] Open
Abstract
Different organisms, cell types, and even similar cell lines can dramatically differ in resistance to genotoxic stress. This testifies to the wide opportunities for genetic and epigenetic regulation of stress resistance. These opportunities could be used to increase the effectiveness of cancer therapy, develop new varieties of plants and animals, and search for new pharmacological targets to enhance human radioresistance, which can be used for manned deep space expeditions. Based on the comparison of transcriptomic studies in cancer cells, in this review, we propose that there is a high diversity of genetic mechanisms of development of genotoxic stress resistance. This review focused on possibilities and limitations of the regulation of the resistance of normal cells and whole organisms to genotoxic and oxidative stress by the overexpressing of stress-response genes. Moreover, the existing experimental data on the effect of such overexpression on the resistance of cells and organisms to various genotoxic agents has been analyzed and systematized. We suggest that the recent advances in the development of multiplex and highly customizable gene overexpression technology that utilizes the mutant Cas9 protein and the abundance of available data on gene functions and their signal networks open new opportunities for research in this field.
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9
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Schosserer M, Grillari J, Breitenbach M. The Dual Role of Cellular Senescence in Developing Tumors and Their Response to Cancer Therapy. Front Oncol 2017; 7:278. [PMID: 29218300 PMCID: PMC5703792 DOI: 10.3389/fonc.2017.00278] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 11/06/2017] [Indexed: 12/11/2022] Open
Abstract
Cellular senescence describes an irreversible growth arrest characterized by distinct morphology, gene expression pattern, and secretory phenotype. The final or intermediate stages of senescence can be reached by different genetic mechanisms and in answer to different external and internal stresses. It has been maintained in the literature but never proven by clearcut experiments that the induction of senescence serves the evolutionary purpose of protecting the individual from development and growth of cancers. This hypothesis was recently scrutinized by new experiments and found to be partly true, but part of the gene activities now known to happen in senescence are also needed for cancer growth, leading to the view that senescence is a double-edged sword in cancer development. In current cancer therapy, cellular senescence is, on the one hand, intended to occur in tumor cells, as thereby the therapeutic outcome is improved, but might, on the other hand, also be induced unintentionally in non-tumor cells, causing inflammation, secondary tumors, and cancer relapse. Importantly, organismic aging leads to accumulation of senescent cells in tissues and organs of aged individuals. Senescent cells can occur transiently, e.g., during embryogenesis or during wound healing, with beneficial effects on tissue homeostasis and regeneration or accumulate chronically in tissues, which detrimentally affects the microenvironment by de- or transdifferentiation of senescent cells and their neighboring stromal cells, loss of tissue specific functionality, and induction of the senescence-associated secretory phenotype, an increased secretory profile consisting of pro-inflammatory and tissue remodeling factors. These factors shape their surroundings toward a pro-carcinogenic microenvironment, which fuels the development of aging-associated cancers together with the accumulation of mutations over time. We are presenting an overview of well-documented stress situations and signals, which induce senescence. Among them, oncogene-induced senescence and stress-induced premature senescence are prominent. New findings about the role of senescence in tumor biology are critically reviewed with respect to new suggestions for cancer therapy leveraging genetic and pharmacological methods to prevent senescence or to selectively kill senescent cells in tumors.
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Affiliation(s)
- Markus Schosserer
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Johannes Grillari
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, Austria.,Christian Doppler Laboratory for Biotechnology of Skin Aging, Vienna, Austria.,Evercyte GmbH, Vienna, Austria
| | - Michael Breitenbach
- Department of Cell Biology, Division of Genetics, University of Salzburg, Salzburg, Austria
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10
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Latorre E, Harries LW. Splicing regulatory factors, ageing and age-related disease. Ageing Res Rev 2017; 36:165-170. [PMID: 28456680 DOI: 10.1016/j.arr.2017.04.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 12/12/2022]
Abstract
Alternative splicing is a co-transcriptional process, which allows for the production of multiple transcripts from a single gene and is emerging as an important control point for gene expression. Alternatively expressed isoforms often have antagonistic function and differential temporal or spatial expression patterns, yielding enormous plasticity and adaptability to cells and increasing their ability to respond to environmental challenge. The regulation of alternative splicing is critical for numerous cellular functions in both pathological and physiological conditions, and deregulated alternative splicing is a key feature of common chronic diseases. Isoform choice is controlled by a battery of splicing regulatory proteins, which include the serine arginine rich (SRSF) proteins and the heterogeneous ribonucleoprotein (hnRNP) classes of genes. These important splicing regulators have been implicated in age-related disease, and in the ageing process itself. This review will outline the important contribution of splicing regulator proteins to ageing and age-related disease.
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11
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Kohlgrüber S, Upadhye A, Dyballa-Rukes N, McNamara CA, Altschmied J. Regulation of Transcription Factors by Reactive Oxygen Species and Nitric Oxide in Vascular Physiology and Pathology. Antioxid Redox Signal 2017; 26:679-699. [PMID: 27841660 PMCID: PMC5421514 DOI: 10.1089/ars.2016.6946] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE Cardiovascular diseases are the main cause of death worldwide and pose an immense economical burden. In most cases, the underlying problem is vascular occlusion by atherosclerotic plaques. Importantly, different cell types of the vascular wall and the immune system play crucial roles in atherosclerosis at different stages of the disease. Furthermore, atherosclerosis and conditions recognized as risk factors are characterized by a reduced availability of the vasoprotective molecule nitric oxide and an increase in reactive oxygen species, so-called oxidative stress. Transcription factors function as intracellular signal integrators and relays and thus, play a central role in cellular responses to changing conditions. Recent Advances: Work on specific transcriptional regulators has uncovered many of their functions and the upstream pathways modulating their activity in response to reactive oxygen and nitrogen species. Here, we have reviewed for a few selected examples how this can contribute not only to protection against atherosclerosis development but also to disease progression and the occurrence of clinical manifestations, such as plaque rupture. CRITICAL ISSUES Transcription factors have pleiotropic outputs and often also divergent functions in different cell types and tissues. Thus, in light of potential severe adverse side effects, a global activation or inhibition of particular transcriptions factors does not seem a feasible therapeutic option. FUTURE DIRECTIONS A further in-depth characterization of the cell- and stage-specific actions and regulation of transcription factors in atherosclerosis with respect to protein-protein interactions and target genes could open up new avenues for prevention or therapeutic interventions in this vascular disease. Antioxid. Redox Signal. 26, 679-699.
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Affiliation(s)
- Stefanie Kohlgrüber
- 1 IUF-Leibniz Research Institute for Environmental Medicine , Düsseldorf, Germany
| | - Aditi Upadhye
- 2 Department of Microbiology, Immunology, Cancer Biology, University of Virginia , Charlottesville, Virginia
| | - Nadine Dyballa-Rukes
- 1 IUF-Leibniz Research Institute for Environmental Medicine , Düsseldorf, Germany
| | - Coleen A McNamara
- 3 Cardiovascular Division, Department of Medicine and Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine , Charlottesville, Virginia
| | - Joachim Altschmied
- 1 IUF-Leibniz Research Institute for Environmental Medicine , Düsseldorf, Germany
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12
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Garschall K, Dellago H, Gáliková M, Schosserer M, Flatt T, Grillari J. Ubiquitous overexpression of the DNA repair factor dPrp19 reduces DNA damage and extends Drosophila life span. NPJ Aging Mech Dis 2017. [PMID: 28649423 PMCID: PMC5445577 DOI: 10.1038/s41514-017-0005-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Mechanisms that ensure and maintain the stability of genetic information are fundamentally important for organismal function and can have a large impact on disease, aging, and life span. While a multi-layered cellular apparatus exists to detect and respond to DNA damage, various insults from environmental and endogenous sources continuously affect DNA integrity. Over time this can lead to the accumulation of somatic mutations, which is thought to be one of the major causes of aging. We have previously found that overexpression of the essential human DNA repair and splicing factor SNEV, also called PRP19 or hPso4, extends replicative life span of cultured human endothelial cells and impedes accumulation of DNA damage. Here, we show that adult-specific overexpression of dPrp19, the D. melanogaster ortholog of human SNEV/PRP19/hPso4, robustly extends life span in female fruit flies. This increase in life span is accompanied by reduced levels of DNA damage and improved resistance to oxidative and genotoxic stress. Our findings suggest that dPrp19 plays an evolutionarily conserved role in aging, life span modulation and stress resistance, and support the notion that superior DNA maintenance is key to longevity. Increasing levels of DNA repair factor Prp19 in fruit flies extends their life span and protects against stress. Prp19 is a protein that is present in a wide range of organisms and enables human endothelial cells to live longer in vitro. In this article, an international team of scientists from Austria, Germany and Switzerland found that higher Prp19 levels also prolong the life span of a whole organism in fruit flies, reduce DNA damage and increase survival when exposed to DNA damaging compounds. In contrast to female flies, males were unaffected. Their findings support the long-held view that repair of DNA damage, one of the hallmarks of aging, is key to longevity. They also provide an intriguing but poorly understood connection between cellular aging and the survival of whole organisms.
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Affiliation(s)
- Kathrin Garschall
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - Hanna Dellago
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Vienna, Austria
| | - Martina Gáliková
- Institut für Populationsgenetik, Vetmeduni Vienna, Vienna Austria.,Department of Developmental Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Markus Schosserer
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Vienna, Austria
| | - Thomas Flatt
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.,Institut für Populationsgenetik, Vetmeduni Vienna, Vienna Austria
| | - Johannes Grillari
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Vienna, Austria.,Christian Doppler Laboratory on Biotechnology of Skin Aging, Dept. of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Vienna, Austria.,Evercyte GmbH, Vienna, Austria
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13
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SNEV hPrp19/hPso4 Regulates Adipogenesis of Human Adipose Stromal Cells. Stem Cell Reports 2016; 8:21-29. [PMID: 28041875 PMCID: PMC5233435 DOI: 10.1016/j.stemcr.2016.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 12/01/2016] [Accepted: 12/01/2016] [Indexed: 11/26/2022] Open
Abstract
Aging is accompanied by loss of subcutaneous adipose tissue. This may be due to reduced differentiation capacity or deficiency in DNA damage repair (DDR) factors. Here we investigated the role of SNEVhPrp19/hPso4, which was implicated in DDR and senescence evasion, in adipogenic differentiation of human adipose stromal cells (hASCs). We showed that SNEV is induced during adipogenesis and localized both in the nucleus and in the cytoplasm. Knockdown of SNEV perturbed adipogenic differentiation and led to accumulation of DNA damage in hASCs upon oxidative stress. In addition, we demonstrated that SNEV is required for fat deposition in Caenorhabditis elegans. Consequently, we tested other DDR factors and found that WRN is also required for adipogenesis in both models. These results demonstrate that SNEV regulates adipogenesis in hASCs and indicate that DDR capacity in general might be a pre-requisite for this process. SNEV is required for adipogenic differentiation of human adipose stromal cells SNEV modulates pro- and anti-adipogenic signaling pathways SNEV regulates DNA repair capacity of human adipose stromal cells SNEV modulates organismal fat deposition in Caenorhabditis elegans
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Monteforte R, Beilhack GF, Grausenburger R, Mayerhofer B, Bittner R, Grillari‐Voglauer R, Sibilia M, Dellago H, Tschachler E, Gruber F, Grillari J. SNEV(Prp19/PSO4) deficiency increases PUVA-induced senescence in mouse skin. Exp Dermatol 2016; 25:212-7. [PMID: 26663487 PMCID: PMC4832318 DOI: 10.1111/exd.12910] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2015] [Indexed: 12/14/2022]
Abstract
Senescent cells accumulate during ageing in various tissues and contribute to organismal ageing. However, factors that are involved in the induction of senescence in vivo are still not well understood. SNEV(P) (rp19/) (PSO) (4) is a multifaceted protein, known to be involved in DNA damage repair and senescence, albeit only in vitro. In this study, we used heterozygous SNEV(+/-) mice (SNEV-knockout results in early embryonic lethality) and wild-type littermate controls as a model to elucidate the role of SNEV(P) (rp19/) (PSO) (4) in DNA damage repair and senescence in vivo. We performed PUVA treatment as model system for potently inducing cellular senescence, consisting of 8-methoxypsoralen in combination with UVA on mouse skin to induce DNA damage and premature skin ageing. We show that SNEV(P) (rp19/) (PSO) (4) expression decreases during organismal ageing, while p16, a marker of ageing in vivo, increases. In response to PUVA treatment, we observed in the skin of both SNEV(P) (rp19/) (PSO) (4) and wild-type mice an increase in γ-H2AX levels, a DNA damage marker. In old SNEV(P) (rp19/) (PSO) (4) mice, this increase is accompanied by reduced epidermis thickening and increase in p16 and collagenase levels. Thus, the DNA damage response occurring in the mouse skin upon PUVA treatment is dependent on SNEV(P) (rp19/) (PSO) (4) expression and lower levels of SNEV(P) (rp19/) (PSO) (4) , as in old SNEV(+/-) mice, result in increase in cellular senescence and acceleration of premature skin ageing.
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Affiliation(s)
- Rossella Monteforte
- Department of BiotechnologyUniversity of Natural Resources and Applied Life SciencesViennaAustria
- Christian Doppler Laboratory on Biotechnology of Skin AgingViennaAustria
| | - Georg F. Beilhack
- Division of Nephrology & DialysisInternal Medicine IIIMedical University of ViennaViennaAustria
| | - Reinhard Grausenburger
- Department of BiotechnologyUniversity of Natural Resources and Applied Life SciencesViennaAustria
- Christian Doppler Laboratory on Biotechnology of Skin AgingViennaAustria
| | - Benjamin Mayerhofer
- Neuromuscular Research DepartmentCenter of Anatomy & Cell BiologyMedical University of ViennaViennaAustria
| | - Reginald Bittner
- Neuromuscular Research DepartmentCenter of Anatomy & Cell BiologyMedical University of ViennaViennaAustria
| | - Regina Grillari‐Voglauer
- Department of BiotechnologyUniversity of Natural Resources and Applied Life SciencesViennaAustria
- Evercyte GmbHViennaAustria
| | - Maria Sibilia
- Institute for Cancer ResearchMedical University of ViennaViennaAustria
| | - Hanna Dellago
- Department of BiotechnologyUniversity of Natural Resources and Applied Life SciencesViennaAustria
- Christian Doppler Laboratory on Biotechnology of Skin AgingViennaAustria
| | - Erwin Tschachler
- Department of DermatologyMedical University of ViennaViennaAustria
| | - Florian Gruber
- Christian Doppler Laboratory on Biotechnology of Skin AgingViennaAustria
- Department of DermatologyMedical University of ViennaViennaAustria
| | - Johannes Grillari
- Department of BiotechnologyUniversity of Natural Resources and Applied Life SciencesViennaAustria
- Christian Doppler Laboratory on Biotechnology of Skin AgingViennaAustria
- Evercyte GmbHViennaAustria
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Schosserer M, Grubeck-Loebenstein B, Grillari J. [Principles of biological aging]. Z Gerontol Geriatr 2015; 48:285-94. [PMID: 25700994 DOI: 10.1007/s00391-015-0857-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/12/2015] [Indexed: 12/01/2022]
Abstract
The aging process is the substrate on which aging-associated diseases develop; therefore, the scientific discipline of gerontology aims at understanding this biological aging process, which refers to the progressive increase in the risk of death caused by a loss of body functions. Studies in simple model organisms demonstrate that pharmacological substances, genetic interventions and dietary restriction can slow down the process of aging. The cell culture model of cellular senescence gives researchers the opportunity to conduct studies in a system more closely related to the human organism; therefore, cells from different human tissues are cultured in vitro until they stop proliferating. This permanent growth arrest is called cellular senescence. Recent studies have demonstrated that senescent cells also accumulate in many tissues in vivo and contribute to age-related pathologies.
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Affiliation(s)
- M Schosserer
- Department für Biotechnologie, BOKU - Universität für Bodenkultur Wien, Muthgasse 18, 1190, Wien, Österreich
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Xu W, Huang H, Yu L, Cao L. Meta-analysis of gene expression profiles indicates genes in spliceosome pathway are up-regulated in hepatocellular carcinoma (HCC). Med Oncol 2015; 32:96. [DOI: 10.1007/s12032-014-0425-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 11/29/2014] [Indexed: 11/25/2022]
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The amazing ubiquitin-proteasome system: structural components and implication in aging. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 314:171-237. [PMID: 25619718 DOI: 10.1016/bs.ircmb.2014.09.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Proteome quality control (PQC) is critical for the maintenance of cellular functionality and it is assured by the curating activity of the proteostasis network (PN). PN is constituted of several complex protein machines that under conditions of proteome instability aim to, firstly identify, and then, either rescue or degrade nonnative polypeptides. Central to the PN functionality is the ubiquitin-proteasome system (UPS) which is composed from the ubiquitin-conjugating enzymes and the proteasome; the latter is a sophisticated multi-subunit molecular machine that functions in a bimodal way as it degrades both short-lived ubiquitinated normal proteins and nonfunctional polypeptides. UPS is also involved in PQC of the nucleus, the endoplasmic reticulum and the mitochondria and it also interacts with the other main cellular degradation axis, namely the autophagy-lysosome system. UPS functionality is optimum in the young organism but it is gradually compromised during aging resulting in increasing proteotoxic stress; these effects correlate not only with aging but also with most age-related diseases. Herein, we present a synopsis of the UPS components and of their functional alterations during cellular senescence or in vivo aging. We propose that mild UPS activation in the young organism will, likely, promote antiaging effects and/or suppress age-related diseases.
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Benjamin AB, Zhou X, Isaac O, Zhao H, Song Y, Chi X, Sun B, Hao L, Zhang L, Liu L, Guan H, Shao S. PRP19 upregulation inhibits cell proliferation in lung adenocarcinomas by p21-mediated induction of cell cycle arrest. Biomed Pharmacother 2014; 68:463-70. [DOI: 10.1016/j.biopha.2014.03.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 03/04/2014] [Indexed: 11/25/2022] Open
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Yin J, Zhang YA, Liu TT, Zhu JM, Shen XZ. DNA damage induces down-regulation of Prp19 via impairing Prp19 stability in hepatocellular carcinoma cells. PLoS One 2014; 9:e89976. [PMID: 24587161 PMCID: PMC3938560 DOI: 10.1371/journal.pone.0089976] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 01/24/2014] [Indexed: 11/18/2022] Open
Abstract
Pre-mRNA processing factor 19 (Prp19) activates pre-mRNA spliceosome and also mediates DNA damage response. Prp19 overexpression in cells with functional p53 leads to decreased apoptosis and increases cell survival after DNA damage. Here we showed that in hepatocellular carcinoma (HCC) cells with inactive p53 or functional p53, Prp19 was down-regulated due to the impaired stability under chemotherapeutic drug treatment. Silencing Prp19 expression enhanced apoptosis of HCC cells with or without chemotherapeutic drug treatment. Furthermore high level of Prp19 may inhibit chemotherapeutic drugs induced apoptosis in hepatocellular carcinoma cells through modulating myeloid leukemia cell differentiation 1 expression. These results indicated that targeting Prp19 may potentiate pro-apoptotic effect of chemotherapeutic agents on HCC.
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Affiliation(s)
- Jie Yin
- Department of Gastroenterology, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Yi-An Zhang
- Department of Gastroenterology, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Tao-Tao Liu
- Department of Gastroenterology, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Ji-Min Zhu
- Department of Gastroenterology, Zhongshan Hospital of Fudan University, Shanghai, China
- * E-mail: (XZS); (JMZ)
| | - Xi-Zhong Shen
- Department of Gastroenterology, Zhongshan Hospital of Fudan University, Shanghai, China
- * E-mail: (XZS); (JMZ)
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Chanarat S, Sträßer K. Splicing and beyond: the many faces of the Prp19 complex. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2126-34. [PMID: 23742842 DOI: 10.1016/j.bbamcr.2013.05.023] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 05/22/2013] [Accepted: 05/24/2013] [Indexed: 12/18/2022]
Abstract
The conserved Prp19 complex (Prp19C) - also known as NineTeen Complex (NTC) - functions in several processes of paramount importance for cellular homeostasis. NTC/Prp19C was discovered as a complex that functions in splicing and more specifically during the catalytic activation of the spliceosome. More recent work revealed that NTC/Prp19C plays a role in transcription elongation in Saccharomyces cerevisiae and in genome maintenance in higher eukaryotes. In addition, mouse PRP19 might ubiquity late proteins targeted for degradation and guide them to the proteasome. Furthermore, NTC/Prp19C has been implicated in lipid droplet biogenesis. In the future, the molecular function of NTC/Prp19C in all of these processes needs to be refined or elucidated. Most of NTC/Prp19C's functions have been shown in only one or few organisms. However, since this complex is highly conserved it is likely that it has the same functions across all species. Moreover, one NTC/Prp19C or different subcomplexes could function in the above-mentioned processes. Intriguingly, NTC/Prp19C might link these different processes to ensure an optimal coordination of cellular processes. Thus, many important questions about the functions of this interesting complex remain to be investigated. In this review we discuss the different functions of NTC/Prp19C focusing on the novel and emerging ones as well as open questions.
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Affiliation(s)
- Sittinan Chanarat
- Department of Molecular Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
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Fang Y, Fu D, Tang W, Cai Y, Ma D, Wang H, Xue R, Liu T, Huang X, Dong L, Wu H, Shen X. Ubiquitin C-terminal Hydrolase 37, a novel predictor for hepatocellular carcinoma recurrence, promotes cell migration and invasion via interacting and deubiquitinating PRP19. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:559-72. [DOI: 10.1016/j.bbamcr.2012.11.020] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 11/11/2012] [Accepted: 11/25/2012] [Indexed: 02/06/2023]
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Löscher M, Schosserer M, Dausse E, Lee K, Ajuh P, Grillari-Voglauer R, Lamond AI, Toulmé JJ, Grillari J. Inhibition of pre-mRNA splicing by a synthetic Blom7α-interacting small RNA. PLoS One 2012; 7:e47497. [PMID: 23144703 PMCID: PMC3483155 DOI: 10.1371/journal.pone.0047497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 09/17/2012] [Indexed: 12/02/2022] Open
Abstract
Originally the novel protein Blom7α was identified as novel pre-mRNA splicing factor that interacts with SNEVPrp19/Pso4, an essential protein involved in extension of human endothelial cell life span, DNA damage repair, the ubiquitin-proteasome system, and pre-mRNA splicing. Blom7α belongs to the heteronuclear ribonucleoprotein K homology (KH) protein family, displaying 2 KH domains, a well conserved and widespread RNA-binding motif. In order to identify specific sequence binding motifs, we here used Systematic Evolution of Ligands by Exponential Enrichment (SELEX) with a synthetic RNA library. Besides sequence motifs like (U/A)1–4 C2–6 (U/A)1–5, we identified an AC-rich RNA-aptamer that we termed AK48 (Aptamer KH-binding 48), binding to Blom7α with high affinity. Addition of AK48 to pre-mRNA splicing reactions in vitro inhibited the formation of mature spliced mRNA and led to a slight accumulation of the H complex of the spliceosome. These results suggest that the RNA binding activity of Blom7α might be required for pre-mRNA splicing catalysis. The inhibition of in-vitro splicing by the small RNA AK48 indicates the potential use of small RNA molecules in targeting the spliceosome complex as a novel target for drug development.
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Affiliation(s)
- Marlies Löscher
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Markus Schosserer
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Eric Dausse
- INSERM U869, European Institute of Chemistry and Biology, Pessac, France
- University of Bordeaux, Bordeaux, France
| | - Kiseok Lee
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Paul Ajuh
- School of Life Sciences, Welcome Trust Biocentre, University of Dundee, Dundee, United Kingdom
| | - Regina Grillari-Voglauer
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
- ACIB, Vienna, Austria
- Evercyte GmbH, Vienna, Austria
| | - Angus I. Lamond
- School of Life Sciences, Welcome Trust Biocentre, University of Dundee, Dundee, United Kingdom
| | - Jean-Jacques Toulmé
- INSERM U869, European Institute of Chemistry and Biology, Pessac, France
- University of Bordeaux, Bordeaux, France
| | - Johannes Grillari
- Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
- Evercyte GmbH, Vienna, Austria
- * E-mail:
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Yin J, Zhu JM, Shen XZ. New insights into pre-mRNA processing factor 19: A multi-faceted protein in humans. Biol Cell 2012; 104:695-705. [DOI: 10.1111/boc.201200011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Accepted: 09/06/2012] [Indexed: 11/27/2022]
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Dellago H, Khan A, Nussbacher M, Gstraunthaler A, Lämmermann I, Schosserer M, Mück C, Anrather D, Scheffold A, Ammerer G, Jansen-Dürr P, Rudolph KL, Voglauer-Grillari R, Grillari J. ATM-dependent phosphorylation of SNEVhPrp19/hPso4 is involved in extending cellular life span and suppression of apoptosis. Aging (Albany NY) 2012; 4:290-304. [PMID: 22529335 PMCID: PMC3371764 DOI: 10.18632/aging.100452] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Defective DNA repair is widely acknowledged to negatively impact on healthy aging, since mutations in DNA repair factors lead to accelerated and premature aging. However, the opposite, namely if improved DNA repair will also increase the life or health span is less clear, and only few studies have tested if overexpression of DNA repair factors modulates life and health span in cells or organisms. Recently, we identified and characterized SNEVhPrp19/hPso4, a protein that plays a role in DNA repair and pre-mRNA splicing, and observed a doubling of the replicative life span upon ectopic overexpression, accompanied by lower basal DNA damage and apoptosis levels as well as an increased resistance to oxidative stress. Here we find that SNEVhPrp19/hPso4 is phosphorylated at S149 in an ataxia telangiectasia mutated protein (ATM)-dependent manner in response to oxidative stress and DNA double strand break inducing agents. By overexpressing wild-type SNEVhPrp19/hPso4 and a phosphorylation-deficient point-mutant, we found that S149 phosphorylation is necessary for mediating the resistance to apoptosis upon oxidative stress and is partially necessary for elongating the cellular life span. Therefore, ATM dependent phosphorylation of SNEVhPrp19/hPso4 upon DNA damage or oxidative stress might represent a novel axis capable of modulating cellular life span.
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Affiliation(s)
- Hanna Dellago
- Department of Biotechnology, University of Natural Resources and Life Sciences Vienna, Vienna, Austria
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HIV-1 induces telomerase activity in monocyte-derived macrophages, possibly safeguarding one of its reservoirs. J Virol 2012; 86:10327-37. [PMID: 22787205 DOI: 10.1128/jvi.01495-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Monocyte-derived macrophages (MDM) are widely distributed in all tissues and organs, including the central nervous system, where they represent the main part of HIV-infected cells. In contrast to activated CD4(+) T lymphocytes, MDM are resistant to cytopathic effects and survive HIV infection for a long period of time. The molecular mechanisms of how HIV is able to persist in macrophages are not fully elucidated yet. In this context, we have studied the effect of in vitro HIV-1 infection on telomerase activity (TA), telomere length, and DNA damage. Infection resulted in a significant induction of TA. This increase was directly proportional to the efficacy of HIV infection and was found in both nuclear and cytoplasmic extracts, while neither UV light-inactivated HIV nor exogenous addition of the viral protein Tat or gp120 affected TA. Furthermore, TA was not modified during monocyte-macrophage differentiation, MDM activation, or infection with vaccinia virus. HIV infection did not affect telomere length. However, HIV-infected MDM showed less DNA damage after oxidative stress than noninfected MDM, and this resistance was also increased by overexpressing telomerase alone. Taken together, our results suggest that HIV induces TA in MDM and that this induction might contribute to cellular protection against oxidative stress, which could be considered a viral strategy to make macrophages better suited as longer-lived, more resistant viral reservoirs. In the light of the clinical development of telomerase inhibitors as anticancer therapeutics, inhibition of TA in HIV-infected macrophages might also represent a novel therapeutic target against viral reservoirs.
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Blanco FJ, Bernabéu C. The Splicing Factor SRSF1 as a Marker for Endothelial Senescence. Front Physiol 2012; 3:54. [PMID: 22470345 PMCID: PMC3314196 DOI: 10.3389/fphys.2012.00054] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 02/26/2012] [Indexed: 01/03/2023] Open
Abstract
Aging is the major risk factor per se for the development of cardiovascular diseases. The senescence of the endothelial cells (ECs) that line the lumen of blood vessels is the cellular basis for these age-dependent vascular pathologies, including atherosclerosis and hypertension. During their lifespan, ECs may reach a stage of senescence by two different pathways; a replicative one derived from their preprogrammed finite number of cell divisions; and one induced by stress stimuli. Also, certain physiological stimuli, such as transforming growth factor-β, are able to modulate cellular senescence. Currently, the cellular aging process is being widely studied to identify novel molecular markers whose changes correlate with senescence. This review focuses on the regulation of alternative splicing mediated by the serine-arginine splicing factor 1 (SRSF1, or ASF/SF2) during endothelial senescence, a process that is associated with a differential subcellular localization of SRSF1, which typically exhibits a scattered distribution throughout the cytoplasm. Based on its senescence-dependent involvement in alternative splicing, we postulate that SRSF1 is a key marker of EC senescence, regulating the expression of alternative isoforms of target genes such as endoglin (ENG), vascular endothelial growth factor A (VEGFA), tissue factor (T3), or lamin A (LMNA) that integrate in a common molecular senescence program.
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Affiliation(s)
- Francisco Javier Blanco
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas and Centro de Investigación Biomédica en Red de Enfermedades Raras Madrid, Spain
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Ungvári I, Hullám G, Antal P, Kiszel PS, Gézsi A, Hadadi É, Virág V, Hajós G, Millinghoffer A, Nagy A, Kiss A, Semsei ÁF, Temesi G, Melegh B, Kisfali P, Széll M, Bikov A, Gálffy G, Tamási L, Falus A, Szalai C. Evaluation of a partial genome screening of two asthma susceptibility regions using bayesian network based bayesian multilevel analysis of relevance. PLoS One 2012; 7:e33573. [PMID: 22432035 PMCID: PMC3303848 DOI: 10.1371/journal.pone.0033573] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 02/15/2012] [Indexed: 01/18/2023] Open
Abstract
Genetic studies indicate high number of potential factors related to asthma. Based on earlier linkage analyses we selected the 11q13 and 14q22 asthma susceptibility regions, for which we designed a partial genome screening study using 145 SNPs in 1201 individuals (436 asthmatic children and 765 controls). The results were evaluated with traditional frequentist methods and we applied a new statistical method, called bayesian network based bayesian multilevel analysis of relevance (BN-BMLA). This method uses bayesian network representation to provide detailed characterization of the relevance of factors, such as joint significance, the type of dependency, and multi-target aspects. We estimated posteriors for these relations within the bayesian statistical framework, in order to estimate the posteriors whether a variable is directly relevant or its association is only mediated.With frequentist methods one SNP (rs3751464 in the FRMD6 gene) provided evidence for an association with asthma (OR = 1.43(1.2-1.8); p = 3×10(-4)). The possible role of the FRMD6 gene in asthma was also confirmed in an animal model and human asthmatics.In the BN-BMLA analysis altogether 5 SNPs in 4 genes were found relevant in connection with asthma phenotype: PRPF19 on chromosome 11, and FRMD6, PTGER2 and PTGDR on chromosome 14. In a subsequent step a partial dataset containing rhinitis and further clinical parameters was used, which allowed the analysis of relevance of SNPs for asthma and multiple targets. These analyses suggested that SNPs in the AHNAK and MS4A2 genes were indirectly associated with asthma. This paper indicates that BN-BMLA explores the relevant factors more comprehensively than traditional statistical methods and extends the scope of strong relevance based methods to include partial relevance, global characterization of relevance and multi-target relevance.
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Affiliation(s)
- Ildikó Ungvári
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Gábor Hullám
- Department of Measurement and Information Systems, University of Technology and Economics, Budapest, Hungary
| | - Péter Antal
- Department of Measurement and Information Systems, University of Technology and Economics, Budapest, Hungary
| | - Petra Sz. Kiszel
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - András Gézsi
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Éva Hadadi
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Viktor Virág
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
| | - Gergely Hajós
- Department of Measurement and Information Systems, University of Technology and Economics, Budapest, Hungary
| | - András Millinghoffer
- Department of Measurement and Information Systems, University of Technology and Economics, Budapest, Hungary
| | | | - András Kiss
- Heim Pal Children Hospital, Budapest, Hungary
| | - Ágnes F. Semsei
- Inflammation Biology and Immunogenomics Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary
| | | | - Béla Melegh
- Department of Medical Genetics, University of Pécs, Pécs, Hungary
| | - Péter Kisfali
- Department of Medical Genetics, University of Pécs, Pécs, Hungary
| | - Márta Széll
- Dermatological Research Group, Hungarian Academy of Sciences, Szeged, Hungary
| | - András Bikov
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Gabriella Gálffy
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - Lilla Tamási
- Department of Pulmonology, Semmelweis University, Budapest, Hungary
| | - András Falus
- Department of Genetics, Cell and Immunobiology, Semmelweis University, Budapest, Hungary
- Inflammation Biology and Immunogenomics Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary
| | - Csaba Szalai
- Heim Pal Children Hospital, Budapest, Hungary
- Inflammation Biology and Immunogenomics Research Group, Hungarian Academy of Sciences, Semmelweis University, Budapest, Hungary
- Csertex Research Laboratory, Budapest, Hungary
- * E-mail:
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Koncz C, deJong F, Villacorta N, Szakonyi D, Koncz Z. The spliceosome-activating complex: molecular mechanisms underlying the function of a pleiotropic regulator. FRONTIERS IN PLANT SCIENCE 2012; 3:9. [PMID: 22639636 PMCID: PMC3355604 DOI: 10.3389/fpls.2012.00009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/09/2012] [Indexed: 05/18/2023]
Abstract
Correct interpretation of the coding capacity of RNA polymerase II transcribed eukaryotic genes is determined by the recognition and removal of intronic sequences of pre-mRNAs by the spliceosome. Our current knowledge on dynamic assembly and subunit interactions of the spliceosome mostly derived from the characterization of yeast, Drosophila, and human spliceosomal complexes formed on model pre-mRNA templates in cell extracts. In addition to sequential structural rearrangements catalyzed by ATP-dependent DExH/D-box RNA helicases, catalytic activation of the spliceosome is critically dependent on its association with the NineTeen Complex (NTC) named after its core E3 ubiquitin ligase subunit PRP19. NTC, isolated recently from Arabidopsis, occurs in a complex with the essential RNA helicase and GTPase subunits of the U5 small nuclear RNA particle that are required for both transesterification reactions of splicing. A compilation of mass spectrometry data available on the composition of NTC and spliceosome complexes purified from different organisms indicates that about half of their conserved homologs are encoded by duplicated genes in Arabidopsis. Thus, while mutations of single genes encoding essential spliceosome and NTC components lead to cell death in other organisms, differential regulation of some of their functionally redundant Arabidopsis homologs permits the isolation of partial loss of function mutations. Non-lethal pleiotropic defects of these mutations provide a unique means for studying the roles of NTC in co-transcriptional assembly of the spliceosome and its crosstalk with DNA repair and cell death signaling pathways.
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Affiliation(s)
- Csaba Koncz
- Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding ResearchCologne, Germany
- Institute of Plant Biology, Biological Research Center of Hungarian Academy of SciencesSzeged, Hungary
- *Correspondence: Csaba Koncz, Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, D-59829 Cologne, Germany. e-mail:
| | - Femke deJong
- Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding ResearchCologne, Germany
| | - Nicolas Villacorta
- Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding ResearchCologne, Germany
| | - Dóra Szakonyi
- Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding ResearchCologne, Germany
| | - Zsuzsa Koncz
- Department of Plant Developmental Biology, Max-Planck Institute for Plant Breeding ResearchCologne, Germany
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Abstract
AbstractRecent work in plant immunity has shown that MOS4, a known intermediate in R protein mediated resistance, is a core member of the nuclear MOS4-associated complex (MAC). This complex is highly conserved in eukaryotes, as orthologous complexes known as the CDC5L-SNEVPrp19-Pso4 complex and the Nineteen complex (NTC) were previously identified in human and yeast, respectively. The involvement of these complexes in pre-mRNA splicing and spliceosome assembly suggests that the MAC probably has a similar function in plants. Double mutants of any two MAC components are lethal, whereas single mutants of the MAC core components mos4, Atcdc5, mac3, and prl1 are all viable and display pleiotropic defects. This suggests that while the MAC is required for some essential biological function such as splicing, individual MAC components are not crucial for complex functionality and likely have regulatory roles in other biological processes such as plant immunity and flowering time control. Future studies on MAC components in Arabidopsis will provide further insight into the regulatory mechanisms of the MAC on specific biological processes.
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31
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Blanco FJ, Bernabeu C. Alternative splicing factor or splicing factor-2 plays a key role in intron retention of the endoglin gene during endothelial senescence. Aging Cell 2011; 10:896-907. [PMID: 21668763 DOI: 10.1111/j.1474-9726.2011.00727.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Alternative splicing involving intron retention plays a key role in the regulation of gene expression. We previously reported that the alternatively spliced short isoform of endoglin (S-endoglin) is induced during the aging or senescence of endothelial cells by a mechanism of intron retention. In this work, we demonstrate that the alternative splicing factor or splicing factor-2 (ASF/SF2) is involved in the synthesis of endoglin. Overexpression of ASF/SF2 in endothelial cells switched the balance between the two endoglin isoforms, favoring the synthesis of S-endoglin. Using a minigene reporter vector and RNA immunoprecipitation experiments, it was shown that ASF/SF2 interacts with the nucleotide sequence of the endoglin minigene, suggesting the direct involvement of ASF/SF2. Accordingly, the sequence recognized by ASF/SF2 in the endoglin gene was identified inside the retained intron near the consensus branch point. Finally, the ASF/SF2 subcellular localization during endothelial senescence showed a preferential scattered distribution throughout the cytoplasm, where it interferes with the activity of the minor spliceosome, leading to an increased expression of S-endoglin mRNA. In summary, we report for the first time the molecular mechanisms by which ASF/SF2 regulates the alternative splicing of endoglin in senescent endothelial cells, as well as the involvement of ASF/SF2 in the minor spliceosome.
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MESH Headings
- Alternative Splicing
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Base Sequence
- Blotting, Western
- Cellular Senescence
- Conserved Sequence
- Cytoplasm/genetics
- Cytoplasm/metabolism
- Endoglin
- Genetic Vectors/genetics
- Genetic Vectors/metabolism
- HEK293 Cells
- Human Umbilical Vein Endothelial Cells
- Humans
- Immunoprecipitation/methods
- Introns
- Microscopy, Fluorescence
- Mutagenesis, Site-Directed
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Alignment
- Sequence Analysis, DNA
- Serine-Arginine Splicing Factors
- Spliceosomes/genetics
- Spliceosomes/metabolism
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Affiliation(s)
- Francisco J Blanco
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, and Centro de Investigación Biomédica en Red de Enfermedades Raras, c/Ramiro de Maeztu 9, Madrid, Spain.
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32
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Dellago H, Löscher M, Ajuh P, Ryder U, Kaisermayer C, Grillari-Voglauer R, Fortschegger K, Gross S, Gstraunthaler A, Borth N, Eisenhaber F, Lamond AI, Grillari J. Exo70, a subunit of the exocyst complex, interacts with SNEV(hPrp19/hPso4) and is involved in pre-mRNA splicing. Biochem J 2011; 438:81-91. [PMID: 21639856 PMCID: PMC3708444 DOI: 10.1042/bj20110183] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The Cdc5L (cell division cycle 5-like) complex is a spliceosomal subcomplex that also plays a role in DNA repair. The complex contains the splicing factor hPrp19, also known as SNEV or hPso4, which is involved in cellular life-span regulation and proteasomal breakdown. In a recent large-scale proteomics analysis for proteins associated with this complex, proteins involved in transcription, cell-cycle regulation, DNA repair, the ubiquitin-proteasome system, chromatin remodelling, cellular aging, the cytoskeleton and trafficking, including four members of the exocyst complex, were identified. In the present paper we report that Exo70 interacts directly with SNEV(hPrp19/hPso4) and shuttles to the nucleus, where it associates with the spliceosome. We mapped the interaction site to the N-terminal 100 amino acids of Exo70, which interfere with pre-mRNA splicing in vitro. Furthermore, Exo70 influences the splicing of a model substrate as well as of its own pre-mRNA in vivo. In addition, we found that Exo70 is alternatively spliced in a cell-type- and cell-age- dependent way. These results suggest a novel and unexpected role of Exo70 in nuclear mRNA splicing, where it might signal membrane events to the splicing apparatus.
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Affiliation(s)
- Hanna Dellago
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Marlies Löscher
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Paul Ajuh
- Department of Gene Expression and Regulation, University of Dundee, Dundee, Scotland, U.K
| | - Ursula Ryder
- Department of Gene Expression and Regulation, University of Dundee, Dundee, Scotland, U.K
| | - Christian Kaisermayer
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | | | - Klaus Fortschegger
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Stefan Gross
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Anna Gstraunthaler
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Nicole Borth
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Frank Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, Singapore 138671
- Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, Singapore 117597
- School of Computater Engineering (SCE), Nanyang Technological University (NTU), 50 Nanyang Drive, Singapore 637553
| | - Angus I. Lamond
- Department of Gene Expression and Regulation, University of Dundee, Dundee, Scotland, U.K
| | - Johannes Grillari
- Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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Proteomic understanding of intracellular responses of recombinant Chinese hamster ovary cells cultivated in serum-free medium supplemented with hydrolysates. Appl Microbiol Biotechnol 2011; 89:1917-28. [PMID: 21286710 DOI: 10.1007/s00253-011-3106-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 12/30/2010] [Accepted: 01/06/2011] [Indexed: 12/11/2022]
Abstract
In order to understand the intracellular responses in recombinant CHO (rCHO) cells producing antibody in serum-free medium (SFM) supplemented with optimized hydrolysates mixtures, yielding the highest specific growth rate (μ, SFM#S1) or the highest specific antibody productivity (q(Ab,) SFM#S2), differentially expressed proteins in rCHO cells are measured by two-dimensional gel electrophoresis combined with nano-LC-ESI-Q-TOF tandem MS. The comparative proteomic analysis with basal SFM without hydrolysates revealed that the addition of hydrolysate mixtures significantly altered the profiles of CHO proteome. In SFM#S1, the expression of metabolism-related proteins, cytoskeleton-associated proteins, and proliferation-related proteins was up-regulated. On the other hand, the expression of anti-proliferative proteins and pro-apoptotic protein was down-regulated. In SFM#S2, the expression of various chaperone proteins and proliferation-linked proteins was altered. 2D-Western blot analysis of differentially expressed proteins confirmed the proteomic results. Taken together, identification of differentially expressed proteins in CHO cells by a proteomic approach can provide insights into understanding the effect of hydrolysates on intracellular events and clues to find candidate genes for cell engineering to maximize the protein production in rCHO cells.
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Grillari J, Grillari-Voglauer R, Jansen-Dürr P. Post-translational modification of cellular proteins by ubiquitin and ubiquitin-like molecules: role in cellular senescence and aging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 694:172-96. [PMID: 20886764 DOI: 10.1007/978-1-4419-7002-2_13] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ubiquitination ofendogenous proteins is one of the key regulatory steps that guides protein degradation through regulation of proteasome activity. During the last years evidence has accumulated that proteasome activity is decreased during the aging process in various model systems and that these changes might be causally related to aging and age-associated diseases. Since in most instances ubiquitination is the primary event in target selection, the system ofubiquitination and deubiquitination might be of similar importance. Furthermore, ubiquitination and proteasomal degradation are not completely congruent, since ubiquitination confers also functions different from targeting proteins for degradation. Depending on mono- and polyubiquitination and on how ubiquitin chains are linked together, post-translational modifications of cellular proteins by covalent attachment of ubiquitin and ubiquitin-like proteins are involved in transcriptional regulation, receptor internalization, DNA repair, stabilization of protein complexes and autophagy. Here, we summarize the current knowledge regarding the ubiquitinome and the underlying ubiquitin ligases and deubiquitinating enzymes in replicative senescence, tissue aging as well as in segmental progeroid syndromes and discuss potential causes and consequences for aging.
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Affiliation(s)
- Johannes Grillari
- Institute of Applied Microbiology, Department of Biotechnology, University for Natural Resources and Applied Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria.
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35
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Hogg R, McGrail JC, O'Keefe RT. The function of the NineTeen Complex (NTC) in regulating spliceosome conformations and fidelity during pre-mRNA splicing. Biochem Soc Trans 2010; 38:1110-5. [PMID: 20659013 PMCID: PMC4234902 DOI: 10.1042/bst0381110] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The NineTeen Complex (NTC) of proteins associates with the spliceosome during pre-mRNA splicing and is essential for both steps of intron removal. The NTC and other NTC-associated proteins are recruited to the spliceosome where they participate in regulating the formation and progression of essential spliceosome conformations required for the two steps of splicing. It is now clear that the NTC is an integral component of active spliceosomes from yeast to humans and provides essential support for the spliceosomal snRNPs (small nuclear ribonucleoproteins). In the present article, we discuss the identification and characterization of the yeast NTC and review recent work in yeast that supports the essential role for this complex in the regulation and fidelity of splicing.
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Affiliation(s)
- Rebecca Hogg
- Faculty of Life Sciences, Michael Smith Building, The University of Manchester, Manchester M13 9PT, UK
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36
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Azizi-Semrad U, Grillari J, Grubeck-Loebenstein B, Pietschmann P. Biogerontology in Austria. Biogerontology 2010; 12:3-10. [PMID: 20195756 DOI: 10.1007/s10522-010-9267-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Accepted: 02/17/2010] [Indexed: 10/19/2022]
Abstract
In Austria significant progress in the field of biogerontology has been achieved in the past years. Biogerontological research is performed in academic and extramural institutions. The Institute for Biomedical Aging Research of the Austrian Academy of Science at Innsbruck is the largest institution dealing with biogerontology in Austria. Moreover, gerontologic research is performed at the Universities of Salzburg and Graz, the Medical Universities of Vienna, Innsbruck and Graz, the University of Veterinary Medicine (Vienna) and the University of Natural Resources and Applied Life Sciences (Vienna). This article describes the work of selected research groups involved in biogerontology in a geographic arrangement.
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Affiliation(s)
- Ursula Azizi-Semrad
- Department of Pathophysiology, Medical University of Vienna, Vienna, Austria
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37
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Grillari J, Löscher M, Denegri M, Lee K, Fortschegger K, Eisenhaber F, Ajuh P, Lamond AI, Katinger H, Grillari-Voglauer R. Blom7alpha is a novel heterogeneous nuclear ribonucleoprotein K homology domain protein involved in pre-mRNA splicing that interacts with SNEVPrp19-Pso4. J Biol Chem 2009; 284:29193-204. [PMID: 19641227 PMCID: PMC2781463 DOI: 10.1074/jbc.m109.036632] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 07/28/2009] [Indexed: 02/05/2023] Open
Abstract
The removal of introns from pre-mRNA is performed by the spliceosome that stepwise assembles on the pre-mRNA before performing two catalytic steps. The spliceosome-associated CDC5L-SNEV(Prp19-Pso4) complex is implicated in activation of the second catalytic step of pre-mRNA splicing, and one of its members, SNEV(Prp19-Pso4), is also implicated in spliceosome assembly. To identify interaction partners of SNEVPrp19-Pso4, we have performed yeast two-hybrid screenings. Among the putative binding partners was a so far uncharacterized protein carrying two heterogeneous nuclear ribonucleoprotein K homology domains that we termed Blom7alpha. Blom7alpha is expressed in all tissues tested, and at least three splice variants exist. After confirming direct and physical interaction of SNEV and Blom7alpha, we investigated if it plays a functional role during pre-mRNA splicing. Indeed, Blom7alpha co-localizes and co-precipitates with splicing factors and pre-mRNA and is present in affinity-purified spliceosomes. More importantly, addition of Blom7alpha to HeLa nuclear extracts increased splicing activity in a dose-dependent manner. Furthermore, we tested if Blom7alpha influences splice site selection using two different minigene constructs. Indeed, both 5'- as well as 3'-site selection was altered upon Blom7alpha overexpression. Thus we suggest that Blom7alpha is a novel splicing factor of the K homology domain family that might be implicated in alternative splicing by helping to position the CDC5L-SNEV(Prp19-Pso4) complex at the splice sites.
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Affiliation(s)
- Johannes Grillari
- Institute of Applied Microbiology, University of Natural Resources and Applied Life Sciences, Vienna A-1190, Austria.
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38
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Abstract
The free radical theory of aging proposes that ROS (reactive oxygen species) are major driving forces of aging, and are also critically involved in cellular senescence. Besides the mitochondrial respiratory chain, alternative sources of ROS have been described that might contribute to cellular senescence. Noxs (NADPH oxidases) are well-known sources of superoxide, which contribute to the antimicrobial capabilities of macrophages, a process involving the prototypical member of the family referred to as Nox2. However, in recent years non-phagocytic homologues of Nox2 have been identified that are involved in processes other than the host defence. Superoxide anions produced by these enzymes are believed to play a major role in signalling by MAPKs (mitogen-activated protein kinases) and stress-activated kinases, but could also contribute to cellular senescence, which is known to involve oxygen radicals. In HUVECs (human umbilical vein endothelial cells), Nox4 is predominantly expressed, but its role in replicative senescence of HUVECs remains to be elucidated. Using shRNA (small-hairpin RNA)-mediated knockdown of Nox4, implicating lentiviral vectors, we addressed the question of whether lifelong depletion of Nox4 in HUVECs would influence the senescent phenotype. We found a significant extension of the replicative lifespan of HUVECs upon knockdown of Nox4. Surprisingly, mean telomere length was significantly reduced in Nox4-depleted cells. Nox4 depletion had no discernable influence on the activity of MAPKs and stress-activated kinases, but reduced the degree of oxidative DNA damage. These results suggest that Nox4 activity increases oxidative damage in HUVECs, leading to loss of replicative potential, which is at least partly independent of telomere attrition.
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Yano K, Shibata S, Chen WL, Sato S, Kaneko T, Jurkiewicz A, Sandal N, Banba M, Imaizumi-Anraku H, Kojima T, Ohtomo R, Szczyglowski K, Stougaard J, Tabata S, Hayashi M, Kouchi H, Umehara Y. CERBERUS, a novel U-box protein containing WD-40 repeats, is required for formation of the infection thread and nodule development in the legume-Rhizobium symbiosis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 60:168-80. [PMID: 19508425 DOI: 10.1111/j.1365-313x.2009.03943.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Endosymbiotic infection of legume plants by Rhizobium bacteria is initiated through infection threads (ITs) which are initiated within and penetrate from root hairs and deliver the endosymbionts into nodule cells. Despite recent progress in understanding the mutual recognition and early symbiotic signaling cascades in host legumes, the molecular mechanisms underlying bacterial infection processes and successive nodule organogenesis are still poorly understood. We isolated a novel symbiotic mutant of Lotus japonicus, cerberus, which shows defects in IT formation and nodule organogenesis. Map-based cloning of the causal gene allowed us to identify the CERBERUS gene, which encodes a novel protein containing a U-box domain and WD-40 repeats. CERBERUS expression was detected in the roots and nodules, and was enhanced after inoculation of Mesorhizobium loti. Strong expression was detected in developing nodule primordia and the infected zone of mature nodules. In cerberus mutants, Rhizobium colonized curled root hair tips, but hardly penetrated into root hair cells. The occasional ITs that were formed inside the root hair cells were mostly arrested within the epidermal cell layer. Nodule organogenesis was aborted prematurely, resulting in the formation of a large number of small bumps which contained no endosymbiotic bacteria. These phenotypic and genetic analyses, together with comparisons with other legume mutants with defects in IT formation, indicate that CERBERUS plays a critical role in the very early steps of IT formation as well as in growth and differentiation of nodules.
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Affiliation(s)
- Koji Yano
- National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan
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Tominaga K, Tominaga E, Ausserlechner MJ, Pereira-Smith OM. The cell senescence inducing gene product MORF4 is regulated by degradation via the ubiquitin/proteasome pathway. Exp Cell Res 2009; 316:92-102. [PMID: 19769966 DOI: 10.1016/j.yexcr.2009.09.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 09/07/2009] [Accepted: 09/15/2009] [Indexed: 12/22/2022]
Abstract
After undergoing several rounds of divisions normal human fibroblasts enter a terminally non-dividing state referred to as cellular or replicative senescence. We cloned MORF4 (mortality factor on human chromosome 4), as a cellular senescence inducing gene that caused immortal cells assigned to complementation group B for indefinite division to stop dividing. To facilitate analyses of this gene, which is toxic to cells at low levels, we obtained stable clones of HeLa cells expressing a tetracycline-induced MORF4 construct that could be induced by doxycycline in a dose-dependent manner. MORF4 induction resulted in reduced colony formation after 14 days of culture, as previously observed. We determined that MORF4 protein was unstable and that addition of the proteasome inhibitor MG132 resulted in the accumulation of the protein. Following removal of MG132 the protein was rapidly degraded. Subcellular fractionation following MG132 treatment demonstrated that the protein accumulates primarily in the cytoplasm with some amounts present in the nucleus. It is therefore possible that MORF4 protein, which escapes degradation in the cytoplasm, is transported to the nucleus where it is functional. The results suggest that levels of MORF4 in cells must be tightly controlled and one mechanism involves stability of the protein.
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Affiliation(s)
- Kaoru Tominaga
- Sam and Ann Barshop Institute for Longevity and Aging Studies UTHSCSA, STCBM, San Antonio, TX 78245, USA.
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Schraml E, Fuchs R, Kotzbeck P, Grillari J, Schauenstein K. Acute adrenergic stress inhibits proliferation of murine hematopoietic progenitor cells via p38/MAPK signaling. Stem Cells Dev 2009; 18:215-27. [PMID: 18444787 DOI: 10.1089/scd.2008.0072] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Acute adrenergic stress is a cause of hematopoietic failure that accompanies severe injury. Although the communication between neuronal and immune system is well documented and catecholamines are known as important regulators of homeostasis, the molecular mechanisms of hematopoietic failure are not well understood. To study the influence of adrenergic stress on hematopoietic progenitor cells (HPCs), which recently have been found to express adrenergic receptors, Lin(-),Sca(+), cells were isolated and treated with alpha- and beta-adrenergic agonists in vitro. Indeed, this stimulation resulted in significantly decreased colony formation capacity using granulocyte/macrophage colony-forming unit assays. This decline was dependent on the formation of reactive oxygen species (ROS) and activation of the p38/mitogen-activated protein kinase (MAPK) pathway, since the addition of antioxidants or a p38 inhibitor restored CFU formation. DNA damage by adrenergically induced ROS, however, does not seem to account for the reduction of colonies. Thus, catecholamine/p38/MAPK is identified as a key signal transduction pathway in HPCs besides those dependent on Wnt, Notch, and sonic hedgehog. Furthermore, a well-known target of p38 signaling, p16 is transcriptionally activated after adrenergic stimulation, suggesting that cell cycle arrest might importantly contribute to hematopoietic failure and immune dysfunctions after severe injury. Since increased levels of catecholamines are also observed in other conditions, such as during aging which is linked with decline of immune functions, adrenergic stress might as well contribute to the lowered immune defence in the elderly.
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Affiliation(s)
- Elisabeth Schraml
- Institute of Pathophysiology and Immunology, Center of Molecular Medicine, Medical University of Graz, Graz, Austria.
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42
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Zeng LR, Park CH, Venu RC, Gough J, Wang GL. Classification, expression pattern, and E3 ligase activity assay of rice U-box-containing proteins. MOLECULAR PLANT 2008; 1:800-15. [PMID: 19825583 DOI: 10.1093/mp/ssn044] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Ubiquitin ligases play a central role in determining the specificity of the ubiquitination system by selecting a myriad of appropriate candidate proteins for modification. The U-box is a recently identified, ubiquitin ligase activity-related protein domain that shows greater presence in plants than in other organisms. In this study, we identified 77 putative U-box proteins from the rice genome using a battery of whole genome analysis algorithms. Most of the U-box protein genes are expressed, as supported by the identification of their corresponding expressed sequence tags (ESTs), full-length cDNAs, or massively parallel signature sequencing (MPSS) tags. Using the same algorithms, we identified 61 U-box proteins from the Arabidopsis genome. The rice and Arabidopsis U-box proteins were classified into nine major classes based on their domain compositions. Comparison between rice and Arabidopsis U-box proteins indicates that the majority of rice and Arabidopsis U-box proteins have the same domain organizations. The inferred phylogeny established the homology between rice and Arabidopsis U-box/ARM proteins. Cell death assay using the rice protoplast system suggests that one rice U-box gene, OsPUB51, might act as a negative regulator of cell death signaling. In addition, the selected U-box proteins were found to be functional E3 ubiquitin ligases. The identification and analysis of rice U-box proteins hereby at the genomic level will help functionally characterize this class of E3 ubiquitin ligase in the future.
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Affiliation(s)
- Li-Rong Zeng
- Department of Plant Pathology, The Ohio State University, Columbus, OH 43210, USA
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43
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Schraml E, Voglauer R, Fortschegger K, Sibilia M, Stelzer I, Grillari J, Schauenstein K. Haploinsufficiency of SNEV Causes Defects of Hematopoietic Stem Cells Functions. Stem Cells Dev 2008; 17:355-66. [DOI: 10.1089/scd.2007.0107] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Elisabeth Schraml
- Institute of Pathophysiology and Immunology, Center of Molecular Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Regina Voglauer
- Institute of Applied Microbiology, BOKU-University of Natural Resources and Applied Life Sciences Vienna, 1190 Vienna, Austria
| | - Klaus Fortschegger
- Institute of Applied Microbiology, BOKU-University of Natural Resources and Applied Life Sciences Vienna, 1190 Vienna, Austria
| | - Maria Sibilia
- Department of Dermatology, Division of Immunology, Allergy and Infectious Diseases, Medical University of Vienna, 1090 Vienna, Austria
- Competence Center for Biomolecular Therapeutics, 1090 Vienna, Austria
| | - Ingeborg Stelzer
- Institute of Pathophysiology and Immunology, Center of Molecular Medicine, Medical University of Graz, 8010 Graz, Austria
| | - Johannes Grillari
- Institute of Applied Microbiology, BOKU-University of Natural Resources and Applied Life Sciences Vienna, 1190 Vienna, Austria
| | - Konrad Schauenstein
- Institute of Pathophysiology and Immunology, Center of Molecular Medicine, Medical University of Graz, 8010 Graz, Austria
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Low telomerase activity: possible role in the progression of human medullary thyroid carcinoma. Eur J Cancer 2008; 44:866-75. [PMID: 18296042 DOI: 10.1016/j.ejca.2007.12.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 12/17/2007] [Accepted: 12/20/2007] [Indexed: 11/22/2022]
Abstract
Maintenance of telomere length has been reported to be an absolute requirement for unlimited growth of human tumour cells and in about 85% of cases, this is achieved by reactivation of telomerase, the enzyme that elongates telomeres. Only in rare cases, like in human medullary thyroid carcinomas (MTC), telomerase activity (TA) is low or undetectable; however, this does not limit tumours to become clinically significant. Here, we report that very low TA (below 5% of HEK293) observed in MTC cell strains derived from different patients, although not sufficient for immortalising the cells, is necessary for prolonging their replicative life span. Telomere erosion led to induction of a crisis period after long-term in vitro cultivation, which was reached earlier when treating the cells with MST-312, a telomerase inhibitor at non-toxic concentrations. Crisis was bypassed either by ectopic hTERT introduction or by infrequent spontaneous immortalisation, the latter of which was always associated with telomerase reactivation and changes of the cellular phenotype. While confirming the high importance of telomerase for tumour development, these data draw attention to the relevance of low TA: although insufficient for telomere stabilisation, it allows MTC cells to reach more population doublings, increasing both cell numbers as well as the risk of accumulating mutations and thus might support the development of clinically significant MTC.
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Grillari J, Katinger H, Voglauer R. Contributions of DNA interstrand cross-links to aging of cells and organisms. Nucleic Acids Res 2007; 35:7566-76. [PMID: 18083760 PMCID: PMC2190700 DOI: 10.1093/nar/gkm1065] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 11/11/2007] [Accepted: 11/11/2007] [Indexed: 01/05/2023] Open
Abstract
Impaired DNA damage repair, especially deficient transcription-coupled nucleotide excision repair, leads to segmental progeroid syndromes in human patients as well as in rodent models. Furthermore, DNA double-strand break signalling has been pinpointed as a key inducer of cellular senescence. Several recent findings suggest that another DNA repair pathway, interstrand cross-link (ICL) repair, might also contribute to cell and organism aging. Therefore, we summarize and discuss here that (i) systemic administration of anti-cancer chemotherapeutics, in many cases DNA cross-linking drugs, induces premature progeroid frailty in long-term survivors; (ii) that ICL-inducing 8-methoxy-psoralen/UVA phototherapy leads to signs of premature skin aging as prominent long-term side effect and (iii) that mutated factors involved in ICL repair like ERCC1/XPF, the Fanconi anaemia proteins, WRN and SNEV lead to reduced replicative life span in vitro and segmental progeroid syndromes in vivo. However, since ICL-inducing drugs cause damage different from ICL and since all currently known ICL repair factors work in more than one pathway, further work will be needed to dissect the actual contribution of ICL damage to aging.
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Affiliation(s)
- Johannes Grillari
- Institute of Applied Microbiology, Department of Biotechnology, BOKU - University of Natural Resources and Applied Life Sciences, Vienna, Muthgasse 18 1190 Vienna, Austria.
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Sihn CR, Cho SY, Lee JH, Lee TR, Kim SH. Mouse homologue of yeast Prp19 interacts with mouse SUG1, the regulatory subunit of 26S proteasome. Biochem Biophys Res Commun 2007; 356:175-80. [PMID: 17349974 DOI: 10.1016/j.bbrc.2007.02.134] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Accepted: 02/20/2007] [Indexed: 11/28/2022]
Abstract
Yeast Prp19 has been shown to involve in pre-mRNA splicing and DNA repair as well as being an ubiquitin ligase. Mammalian homologue of yeast Prp19 also plays on similar functional activities in cells. In the present study, we isolated mouse SUG1 (mSUG1) as binding partner of mouse Prp19 (mPrp19) by the yeast two-hybrid system. We confirmed the interaction of mPrp9 with mSUG1 by GST pull-down assay and co-immunoprecipitation assay. The N-terminus of mPrp19 including U-box domain was associated with the C-terminus of mSUG1. Although, mSUG1 is a regulatory subunit of 26S proteasome, mPrp19 was not degraded in the proteasome-dependent pathway. Interestingly, GFP-mPrp19 fusion protein was co-localized with mSUG1 protein in cytoplasm as the formation of the speckle-like structures in the presence of a proteasome inhibitor MG132. In addition, the activity of proteasome was increased in cells transfected with mPrp19. Taken together, these results suggest that mPrp19 involves the regulation of protein turnover and may transport its substrates to 26S proteasome through mSUG1 protein.
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Affiliation(s)
- Choong-Ryoul Sihn
- Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea
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Fortschegger K, Wagner B, Voglauer R, Katinger H, Sibilia M, Grillari J. Early embryonic lethality of mice lacking the essential protein SNEV. Mol Cell Biol 2007; 27:3123-30. [PMID: 17283042 PMCID: PMC1899945 DOI: 10.1128/mcb.01188-06] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SNEV (Prp19, Pso4, NMP200) is a nuclear matrix protein known to be involved in pre-mRNA splicing, ubiquitylation, and DNA repair. In human umbilical vein endothelial cells, SNEV overexpression delayed the onset of replicative senescence. Here we analyzed the function of the mouse SNEV gene in vivo by employing homologous recombination in mice and conclude that SNEV is indispensable for early mouse development. Mutant preimplantation embryos initiated blastocyst formation but died shortly thereafter. Outgrowth of SNEV-null blastocysts showed a lack of proliferation of cells of the inner cell mass, which subsequently underwent cell death. While SNEV-heterozygous mice showed no overt phenotype, heterozygous mouse embryonic fibroblast cell lines with reduced SNEV levels displayed a decreased proliferative potential in vitro. Our experiments demonstrate that the SNEV protein is essential, functionally nonredundant, and indispensable for mouse development.
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Lu X, Legerski RJ. The Prp19/Pso4 core complex undergoes ubiquitylation and structural alterations in response to DNA damage. Biochem Biophys Res Commun 2007; 354:968-74. [PMID: 17276391 PMCID: PMC1810354 DOI: 10.1016/j.bbrc.2007.01.097] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Accepted: 01/17/2007] [Indexed: 11/17/2022]
Abstract
Prp19/Pso4, a U-box containing E3 ligase, has a demonstrated role in pre-mRNA splicing, but has also been implicated in both yeast and mammalian cells as having a direct role in DNA damage processing. In this report, we provide further evidence in support of this latter assertion. We show that hPrp19 forms an ubiquitylated oligomeric species that is resistant to disruption by SDS gel electrophoresis under nonreducing conditions suggesting that is mediated by a thiolester between ubiquitin and a cysteine residue in Prp19. The level of this species is significantly enhanced upon treatment of cells with DNA damaging agents, and its association with chromatin is increased. In addition, hPrp19 is known to form a stable core complex with Cdc5L, Plrg1, and Spf27; however, ubiquitylated hPrp19 fails to interact with either Cdc5L or Plrg1 indicating that DNA damage can induce profound alterations to the hPrp19 core complex. Finally, we show that overexpression of hPrp19 in human cells provides a pro-survival affect in that it reduces the levels of apoptosis observed after exposure of cells to DNA damage.
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Grillari J, Katinger H, Voglauer R. Aging and the ubiquitinome: traditional and non-traditional functions of ubiquitin in aging cells and tissues. Exp Gerontol 2006; 41:1067-79. [PMID: 17052881 DOI: 10.1016/j.exger.2006.07.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2006] [Revised: 07/13/2006] [Accepted: 07/18/2006] [Indexed: 01/01/2023]
Abstract
Ubiquitination of endogenous proteins is one of the key regulatory steps of protein degradation followed by regulation of proteasome activity. During the last years evidence has increased that proteasome activity is decreased during the aging process in various model systems and that these changes might be causally related to aging and aging associated diseases. Since in most instances ubiquitination is the primary event in target selection, the system of ubiquitination and deubiquitination might be of similar importance. Furthermore, ubiquitination and proteasomal degradation are not completely congruent, since ubiquitination also confers functions different from giving "the kiss of death" to proteins. Depending on mono- and polyubiquitination and on how ubiquitin chains are linked together, ubiquitination is involved in transcriptional regulation, receptor internalization, DNA repair, and stabilization of protein complexes. This review is therefore the first to summarize the current knowledge regarding the ubiquitinome and the underlying ubiquitin ligases and deubiquitinating enzymes in replicative senescence, tissue aging as well as in segmental progeroid syndromes and to discuss potential causes and consequences for aging.
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Affiliation(s)
- Johannes Grillari
- Department of Biotechnology, Institute of Applied Microbiology, University of Natural Resources and Applied Life Sciences, Vienna Muthgasse 18, A-1190 Vienna, Austria.
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Abstract
The wear and tear processes that are thought to contribute to human ageing may play an important role in the development of vascular diseases. One such process is cellular senescence. In endothelial cells the senescent phenotype can be induced by a number of factors, including telomere damage, oxidative stress and sustained mitogenic stimulation. Several lines of evidence indicate that endothelial cell senescence maybe relevant to vascular disease. In this chapter we examine the causes, mechanisms and regulation of endothelial cell senescence as they emerge from studies in cell culture. We also describe the senescent phenotype and discuss its pathophysiological implications. We review the evidence for the occurrence of endothelial cell senescence in vivo and examine findings in animal models of ageing and human genetic disorders that argue for and against a role of endothelial cell senescence in age-related vascular pathology. Finally, we address the particular case of endothelial progenitor cell senescence and discuss the relevance of this phenomenon for angiogenesis and vascular repair.
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Affiliation(s)
- J D Erusalimsky
- Cardiff School of Health Sciences, University of Wales Institute Cardiff, Llandaff Campus, Western Avenue, Cardiff CF5 2YB, UK.
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