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Wang C, Huang Y, Yang Y, Li R, Li Y, Qiu H, Wu J, Shi G, Ma W, Songyang Z. ILF3 safeguards telomeres from aberrant homologous recombination as a telomeric R-loop reader. Protein Cell 2024; 15:493-511. [PMID: 37991243 PMCID: PMC11214836 DOI: 10.1093/procel/pwad054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 10/09/2023] [Indexed: 11/23/2023] Open
Abstract
Telomeres are specialized structures at the ends of linear chromosomes that protect genome stability. The telomeric repeat-containing RNA (TERRA) that is transcribed from subtelomeric regions can invade into double-stranded DNA regions and form RNA:DNA hybrid-containing structure called R-loop. In tumor cells, R-loop formation is closely linked to gene expression and the alternative lengthening of telomeres (ALT) pathway. Dysregulated R-loops can cause stalled replication forks and telomere instability. However, how R-loops are recognized and regulated, particularly at telomeres, is not well understood. We discovered that ILF3 selectively associates with telomeric R-loops and safeguards telomeres from abnormal homologous recombination. Knocking out ILF3 results in excessive R-loops at telomeres and triggers telomeric DNA damage responses. In addition, ILF3 deficiency disrupts telomere homeostasis and causes abnormalities in the ALT pathway. Using the proximity-dependent biotin identification (BioID) technology, we mapped the ILF3 interactome and discovered that ILF3 could interact with several DNA/RNA helicases, including DHX9. Importantly, ILF3 may aid in the resolution of telomeric R-loops through its interaction with DHX9. Our findings suggest that ILF3 may function as a reader of telomeric R-loops, helping to prevent abnormal homologous recombination and maintain telomere homeostasis.
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Affiliation(s)
- Chuanle Wang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
- Department of Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
| | - Yan Huang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yue Yang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China
| | - Ruofei Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Yingying Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Hongxin Qiu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Jiali Wu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Guang Shi
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Wenbin Ma
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Zhou Songyang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol and Guangzhou Key Laboratory of Healthy Aging, School of Lifesciences, Sun Yat-sen University, Guangzhou 510275, China
- Department of Oncology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510275, China
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Shepelev N, Dontsova O, Rubtsova M. Post-Transcriptional and Post-Translational Modifications in Telomerase Biogenesis and Recruitment to Telomeres. Int J Mol Sci 2023; 24:5027. [PMID: 36902458 PMCID: PMC10003056 DOI: 10.3390/ijms24055027] [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: 02/02/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Telomere length is associated with the proliferative potential of cells. Telomerase is an enzyme that elongates telomeres throughout the entire lifespan of an organism in stem cells, germ cells, and cells of constantly renewed tissues. It is activated during cellular division, including regeneration and immune responses. The biogenesis of telomerase components and their assembly and functional localization to the telomere is a complex system regulated at multiple levels, where each step must be tuned to the cellular requirements. Any defect in the function or localization of the components of the telomerase biogenesis and functional system will affect the maintenance of telomere length, which is critical to the processes of regeneration, immune response, embryonic development, and cancer progression. An understanding of the regulatory mechanisms of telomerase biogenesis and activity is necessary for the development of approaches toward manipulating telomerase to influence these processes. The present review focuses on the molecular mechanisms involved in the major steps of telomerase regulation and the role of post-transcriptional and post-translational modifications in telomerase biogenesis and function in yeast and vertebrates.
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Affiliation(s)
- Nikita Shepelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Olga Dontsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Maria Rubtsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
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Zhou J, Chen F, Yan A, Xia X. Explore the molecular mechanism of angle-closure glaucoma in elderly patients induced telomere shortening of retinal ganglion cells through oxidative stress. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2022; 41:1024-1035. [PMID: 35802889 DOI: 10.1080/15257770.2022.2094947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Senile glaucoma is a common ophthalmological disease in the elderly. It is a disease of visual papillary perfusion caused by elevated intraocular pressure, complicated by visual dysfunction. Glaucoma can cause serious damage to the normal vision of the elderly. Therefore, exploring the related molecular mechanisms of glaucoma is of great significance to the diagnosis and treatment of glaucoma. This is an exploratory study. Establish a mouse model and conduct experimental groupings. After one week of adaptive feeding, the mice were intraperitoneally injected with an anesthetic mixture: ketamine + xylazine. Then the mice were sacrificed by neck dissection, and the eyeball tissues were immediately dissected. HE staining was used to analyze the histopathological characteristics of the retina of each group of mice. MitoSOX fluorescent probe was used to analyze the content of ROS in retinal tissue. The ELISA analysis was used to detect the activation of β-galactosidase for the aging characteristics of retinal ganglion cells in retinal tissues. Immunohistochemistry experiments were used to analyze the expression of telomerase TERT in retinal tissues. Western blot analysis was used to determine the expression of proteins POT1, TERF1, TERF2, and TINF2 in retinal tissues. The HE staining experiment showed that the damage of retinal tissue decreased from group Glaucoma to group Old, group Old to group Young. The experimental results of MitoSOX fluorescent probe show that ROS content is positively correlated with the degree of tissue damage. ELISA analysis results showed that the expression trend of β-galactosidase was the same as the ROS content. The protein expression levels related to telomere protection (TRET, POT1, TREF1, TREF2 and TINF2) all increased from group Glaucoma to group Old, group Old to group Young. The increase in ROS content, the decrease in telomere protection-related protein expression (telomere shortening) induced by ROS, and the increase of the expression of β-galactosidase, are all potential molecular mechanisms for the occurrence of angle-closure glaucoma in elderly patients.
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Affiliation(s)
- Jinzi Zhou
- Department of Ophthalmology, The First People's Hospital of Guiyang, Guiyang, P.R. China
| | - Fenghua Chen
- Department of Ophthalmology, The First People's Hospital of Guiyang, Guiyang, P.R. China
| | - Aimin Yan
- Department of Ophthalmology, The First People's Hospital of Guiyang, Guiyang, P.R. China
| | - Xiaobo Xia
- Department of Ophthalmology, Xiangya Hospital Central South University, Changsha, P.R. China
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Bohnsack KE, Ficner R, Bohnsack MT, Jonas S. Regulation of DEAH-box RNA helicases by G-patch proteins. Biol Chem 2021; 402:561-579. [PMID: 33857358 DOI: 10.1515/hsz-2020-0338] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/09/2020] [Indexed: 12/22/2022]
Abstract
RNA helicases of the DEAH/RHA family form a large and conserved class of enzymes that remodel RNA protein complexes (RNPs) by translocating along the RNA. Driven by ATP hydrolysis, they exert force to dissociate hybridized RNAs, dislocate bound proteins or unwind secondary structure elements in RNAs. The sub-cellular localization of DEAH-helicases and their concomitant association with different pathways in RNA metabolism, such as pre-mRNA splicing or ribosome biogenesis, can be guided by cofactor proteins that specifically recruit and simultaneously activate them. Here we review the mode of action of a large class of DEAH-specific adaptor proteins of the G-patch family. Defined only by their eponymous short glycine-rich motif, which is sufficient for helicase binding and stimulation, this family encompasses an immensely varied array of domain compositions and is linked to an equally diverse set of functions. G-patch proteins are conserved throughout eukaryotes and are even encoded within retroviruses. They are involved in mRNA, rRNA and snoRNA maturation, telomere maintenance and the innate immune response. Only recently was the structural and mechanistic basis for their helicase enhancing activity determined. We summarize the molecular and functional details of G-patch-mediated helicase regulation in their associated pathways and their involvement in human diseases.
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Affiliation(s)
- Katherine E Bohnsack
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Ralf Ficner
- Department of Molecular Structural Biology, Institute of Microbiology and Genetics, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany.,Göttingen Centre for Molecular Biosciences, Georg-August University, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| | - Markus T Bohnsack
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany.,Göttingen Centre for Molecular Biosciences, Georg-August University, Justus-von-Liebig-Weg 11, D-37077 Göttingen, Germany
| | - Stefanie Jonas
- Department of Biology, Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, CH-8093 Zurich, Switzerland
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Schrumpfová PP, Fajkus J. Composition and Function of Telomerase-A Polymerase Associated with the Origin of Eukaryotes. Biomolecules 2020; 10:biom10101425. [PMID: 33050064 PMCID: PMC7658794 DOI: 10.3390/biom10101425] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 12/19/2022] Open
Abstract
The canonical DNA polymerases involved in the replication of the genome are unable to fully replicate the physical ends of linear chromosomes, called telomeres. Chromosomal termini thus become shortened in each cell cycle. The maintenance of telomeres requires telomerase—a specific RNA-dependent DNA polymerase enzyme complex that carries its own RNA template and adds telomeric repeats to the ends of chromosomes using a reverse transcription mechanism. Both core subunits of telomerase—its catalytic telomerase reverse transcriptase (TERT) subunit and telomerase RNA (TR) component—were identified in quick succession in Tetrahymena more than 30 years ago. Since then, both telomerase subunits have been described in various organisms including yeasts, mammals, birds, reptiles and fish. Despite the fact that telomerase activity in plants was described 25 years ago and the TERT subunit four years later, a genuine plant TR has only recently been identified by our group. In this review, we focus on the structure, composition and function of telomerases. In addition, we discuss the origin and phylogenetic divergence of this unique RNA-dependent DNA polymerase as a witness of early eukaryotic evolution. Specifically, we discuss the latest information regarding the recently discovered TR component in plants, its conservation and its structural features.
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Affiliation(s)
- Petra Procházková Schrumpfová
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic;
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic
- Correspondence:
| | - Jiří Fajkus
- Laboratory of Functional Genomics and Proteomics, National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kotlářská 2, CZ-61137 Brno, Czech Republic;
- Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-62500 Brno, Czech Republic
- The Czech Academy of Sciences, Institute of Biophysics, Královopolská 135, 612 65 Brno, Czech Republic
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Telomerase Biogenesis and Activities from the Perspective of Its Direct Interacting Partners. Cancers (Basel) 2020; 12:cancers12061679. [PMID: 32599885 PMCID: PMC7352425 DOI: 10.3390/cancers12061679] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/20/2020] [Accepted: 06/22/2020] [Indexed: 12/15/2022] Open
Abstract
Telomerase reverse transcriptase (TERT)—the catalytic subunit of telomerase—is reactivated in up to 90% of all human cancers. TERT is observed in heterogenous populations of protein complexes, which are dynamically regulated in a cell type- and cell cycle-specific manner. Over the past two decades, in vitro protein–protein interaction detection methods have discovered a number of endogenous TERT binding partners in human cells that are responsible for the biogenesis and functionalization of the telomerase holoenzyme, including the processes of TERT trafficking between subcellular compartments, assembly into telomerase, and catalytic action at telomeres. Additionally, TERT have been found to interact with protein species with no known telomeric functions, suggesting that these complexes may contribute to non-canonical activities of TERT. Here, we survey TERT direct binding partners and discuss their contributions to TERT biogenesis and functions. The goal is to review the comprehensive spectrum of TERT pro-malignant activities, both telomeric and non-telomeric, which may explain the prevalence of its upregulation in cancer.
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Ho ST, Jin R, Cheung DHC, Huang JJ, Shaw PC. The PinX1/NPM interaction associates with hTERT in early-S phase and facilitates telomerase activation. Cell Biosci 2019; 9:47. [PMID: 31210926 PMCID: PMC6567508 DOI: 10.1186/s13578-019-0306-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 05/23/2019] [Indexed: 01/26/2023] Open
Abstract
Background Telomere maintenance is an important factor in tumorigenesis. PinX1 is a potent telomerase regulator which also involves in telomerase loading to telomeres. Nucleophosmin (NPM) can partially attenuate PinX1 inhibition of telomerase activity and NPM loading to hTERT requires PinX1. However, the role of the PinX1/NPM interaction in telomerase activity is not fully understood. Method The long-term effects of PinX1 and NPM down-regulation on telomere length were investigated by TRF assay. The localization of the PinX1/NPM association and the NPM/PinX1/hTERT complex formation were examined by immunofluorescence studies. Results Concurrent long-term down-regulation of PinX1 and NPM led to a substantial decrease in telomere length. The interaction with PinX1 was crucial in NPM localization in the nucleolus during the S phase. PinX1 and NPM associated throughout S phase and the NPM/PinX1/hTERT complex formation peaked during the early-S phase. The PinX1/NPM interaction was shown to localize away from Cajal Bodies at the start of S phase. Conclusion PinX1/NPM interaction is important in telomerase regulation during catalysis. NPM is recruited to hTERT by PinX1 and is required in the proposed telomerase modulating unit to activate telomerase when telomere extension occurs during S phase. Electronic supplementary material The online version of this article (10.1186/s13578-019-0306-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sai-Tim Ho
- 1Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China
| | - Rui Jin
- 2Laboratory of Tumor and Molecular Biology, Beijing Institute of Biotechnology, Beijing, China
| | - Derek Hang-Cheong Cheung
- 1Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China
| | - Jun-Jian Huang
- 2Laboratory of Tumor and Molecular Biology, Beijing Institute of Biotechnology, Beijing, China
| | - Pang-Chui Shaw
- 1Centre for Protein Science and Crystallography, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T, Hong Kong, China
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Electrochemical determination of the activity and inhibition of telomerase based on the interaction of DNA with molybdate. Mikrochim Acta 2019; 186:96. [PMID: 30631950 DOI: 10.1007/s00604-018-3223-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 12/29/2018] [Indexed: 01/19/2023]
Abstract
An ultrasensitive electrochemical sensor is described for the determination of the activity of telomerase. It is based on a DNA-generated current that is due to the reaction of the phosphate groups on DNA with molybdate to form a redox-active molybdophosphate. A telomerase substrate primer was first immobilized on a gold electrode. In the presence of telomerase and deoxyribonucleoside triphosphates (dNTPs), the primer can be extended with repetitive nucleotide sequences (TTAGGG). The subsequent reaction of the sensor with molybdate results in the enhancement of electrochemical current intensity due to an increased amount of nucleotides on the electrode. Sensitivity can be further improved by introducing a hairpin probe that partially hybridizes with the repetitive TTAGGG sequence and further enhances the amount of DNA on the electrode. The biosensor, best operated at 0.2 V (vs. Ag/AgCl) shows a linear response to telomerase activity from 1×102 to 107 Hela cells mL-1. The assay was applied to the detection of telomerase activity in HeLa cancer cells treated with the anticancer drug epigallocatechin gallate, and the results indicate that it holds great potential in anticancer drug screening. Graphical abstract Schematic presentation of an ultrasensitive electrochemical sensor for the determination of telomerase activity based on DNA generated electrochemical current. dNTPs in the scheme represents deoxyribonucleoside triphosphates.
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Viviescas MA, Cano MIN, Segatto M. Chaperones and Their Role in Telomerase Ribonucleoprotein Biogenesis and Telomere Maintenance. CURR PROTEOMICS 2018. [DOI: 10.2174/1570164615666180713103133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Telomere length maintenance is important for genome stability and cell division. In most
eukaryotes, telomeres are maintained by the telomerase ribonucleoprotein (RNP) complex, minimally
composed of the Telomerase Reverse Transcriptase (TERT) and the telomerase RNA (TER) components.
In addition to TERT and TER, other protein subunits are part of the complex and are involved in
telomerase regulation, assembly, disassembly, and degradation. Among them are some molecular
chaperones such as Hsp90 and its co-chaperone p23 which are found associated with the telomerase
RNP complex in humans, yeast and probably in protozoa. Hsp90 and p23 are necessary for the telomerase
RNP assembly and enzyme activity. In budding yeast, the Hsp90 homolog (Hsp82) is also responsible
for the association and dissociation of telomerase from the telomeric DNA by its direct interaction
with a telomere end-binding protein (Cdc13), responsible for regulating telomerase access to telomeres.
In addition, AAA+ ATPases, such as Pontin and Reptin, which are also considered chaperone-
like proteins, associate with the human telomerase complex by the direct interaction of Pontin with
TERT and dyskerin. They are probably responsible for telomerase RNP assembly since their depletion
impairs the accumulation of the complex. Moreover, various RNA chaperones, are also pivotal in the
assembly and migration of the mature telomerase complex and complex intermediates. In this review,
we will focus on the importance of molecular chaperones for telomerase RNP biogenesis and how they
impact telomere length maintenance and cellular homeostasis.
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Affiliation(s)
- Maria Alejandra Viviescas
- Genetics Department, Biosciences Institute, Sao Paulo State University (UNESP), Botucatu, SP, Brazil
| | | | - Marcela Segatto
- Genetics Department, Biosciences Institute, Sao Paulo State University (UNESP), Botucatu, SP, Brazil
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Su D, Huang X, Dong C, Ren J. Quantitative Determination of Telomerase Activity by Combining Fluorescence Correlation Spectroscopy with Telomerase Repeat Amplification Protocol. Anal Chem 2017; 90:1006-1013. [PMID: 29211436 DOI: 10.1021/acs.analchem.7b04256] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Telomerase is a key enzyme for maintaining the telomere length and is regarded as a versatile cancer biomarker and a potential drug target due to its important role in cancer and aging. It is necessary to develop a sensitive and reliable method for detection of telomerase activity due to its very low level in cells. In this Article, we propose an ultrasensitive and robust method for quantitative determination of telomerase activity by combining single molecule fluorescence correlation spectroscopy (FCS) with telomerase repeat amplification protocol (TRAP). The principle of this new method (FCS-TRAP) is based on measurement of the change in characteristic diffusion time and molecule number of TRAP products by FCS. The characteristic diffusion time is related to the length of TRAP products, and the molecule number represents the concentration of TRAP products. We optimized the conditions of TRAP procedure and FCS measurements. We observed that the telomerase activities are positively correlated to characteristic diffusion time and molecule number of TRAP products at optimal conditions. This method was successfully used for determination of telomerase activity of different cells, and detection of a single cell was realized. Meanwhile, this method was used to evaluate the inhibition efficiency of inhibitors, and the IC50 values obtained were in good agreement with the references. Compared to current TRAP methods, this method shows reliable quantification, ultrahigh sensitivity, and short detection time and is without separation. We believe that the FCS-TRAP method has a potential application in clinical diagnosis and screening of telomerase inhibitors.
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Affiliation(s)
- Di Su
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Xiangyi Huang
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Chaoqing Dong
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai, 200240, P. R. China
| | - Jicun Ren
- School of Chemistry & Chemical Engineering, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University , 800 Dongchuan Road, Shanghai, 200240, P. R. China
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11
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Zhang QH, Yin RX, Huang F, Yang DZ, Lin WX, Pan SL. Association between the PINX1 and NAT2 polymorphisms and serum lipid levels. Oncotarget 2017; 8:114081-114094. [PMID: 29371971 PMCID: PMC5768388 DOI: 10.18632/oncotarget.23123] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/29/2017] [Indexed: 02/07/2023] Open
Abstract
Jing nationality is a relatively conservative and isolated minority in China. Little is known about the association of the PIN2/TERF1-interacting telomerase inhibitor 1 (PINX1) and N-acetyltransferase 2 (NAT2) single nucleotide polymorphisms (SNPs) and serum lipid levels in the Chinese populations. This study aimed to clarify the association of 6 SNPs of the PINX1 and NAT2 and serum lipid levels in two Chinese populations. Genotyping of the SNPs was performed in 1236 Han subjects and 1248 Jing participants. Allelic and genotypic frequencies of these variants (except NAT2 rs1799931) were different between the two ethnic groups. The minor allele carriers had higher triglyceride (TG, rs11776767, rs1495743 and rs1799930), low-density lipoprotein cholesterol (rs6601530) levels and the apolipoprotein (Apo)A1/ApoB ratio (rs1495743) in Han nationality; and higher total cholesterol (rs1961456), TG (rs11776767, rs6601530 and rs1495743) and lower ApoA1 (rs6601530 and rs1799931) levels in Jing minority than the minor allele non-carriers. The SNPs were not statistically independent by the multiple-locus linkage disequilibrium analyses. The integrative haplotypes and gene-by-gene (G × G) interactions on serum lipid traits were also observed in the two populations. Association analysis based on haplotypes and G × G interactions might be powerful than single-locus tests. Differences in serum lipid profiles between the two populations might partially be attributed to these SNPs, their haplotypes and G × G interactions.
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Affiliation(s)
- Qing-Hui Zhang
- Department of Cardiology, Institute of Cardiovascular Diseases, The First Affiliated Hospital, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
| | - Rui-Xing Yin
- Department of Cardiology, Institute of Cardiovascular Diseases, The First Affiliated Hospital, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
| | - Feng Huang
- Department of Cardiology, Institute of Cardiovascular Diseases, The First Affiliated Hospital, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
| | - De-Zhai Yang
- Department of Molecular Genetics, Medical Scientific Research Center, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
| | - Wei-Xiong Lin
- Department of Molecular Genetics, Medical Scientific Research Center, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
| | - Shang-Ling Pan
- Department of Pathophysiology, School of Premedical Sciences, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
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Huang WJ, Li M, Jin XH, Huang XJ, Zhao W, Tian XP. Genetic profile and biological implication of PIN2/TRF1-interacting telomerase inhibitor 1 (PinX1) in human cancers: an analysis using The Cancer Genome Atlas. Oncotarget 2017; 8:67241-67253. [PMID: 28978030 PMCID: PMC5620170 DOI: 10.18632/oncotarget.18589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 05/03/2017] [Indexed: 12/15/2022] Open
Abstract
Pin2/TRF1-interacting telomere inhibitor 1 (PinX1) was originally identified as a telomerase inhibitor, involved in maintaining telomerase activity, telomere length, and chromosomal stability. However, research has shown that PinX1 can have opposing molecular status in its expression patterns in several other tumor types. We thus investigated the genetic profile and biological implication of PinX1 in several human cancers using the cBioportal database. Our results showed that PinX1 deletion accounted for the most alterations, with the frequency of its deletion regularly occurring in pathological types of carcinosarcoma and adenocarcinoma. We found few instances of PinX1 gene mutations and 3D structural analysis demonstrated that these mutation sites were always located within telomerase inhibitor domains. Furthermore, our analysis of several human cancers from the cBioportal database revealed more frequent PinX1 homozygous depletion and PinX1 heterozygous deficiency, but both more infrequent PinX1 gain and rare instances of PinX1 amplification. The status of PinX1 genetic alterations was correlated with prognosis and may be tumor-type specific. As such, its biological function in tumorigenesis and later prognosis is complicated and may involve co-worked with NEIL2, R3HCC1, POLR3D, GTF2E2, and INTS10. In addition, we observed that PinX1 interacts with TERT, DKC1, PTGES3, and HSP90AA1. PinX1 mRNA expression was decreased in most selected cancer tissues, which could promote tumor growth and enhance tumorigenicity. Collectively, our data reveal PinX1 expression patterns and potential mechanisms in various human cancers. Further work will be needed to comprehensively examine its role in tumor genesis and progression.
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Affiliation(s)
- Wei-Juan Huang
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China.,Department of Pharmacology, Jinan University, Guangzhou, China
| | - Mei Li
- Department of Pathology, Cancer Center, Sun Yat-Sen University, Guangzhou, China
| | - Xiao-Han Jin
- The State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
| | - Xiao-Jia Huang
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Wei Zhao
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China
| | - Xiao-Peng Tian
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China.,The State Key Laboratory of Oncology in South China, Sun Yat-Sen University Cancer Center, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China
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