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Mashayekhi F, Zeinali E, Ganje C, Fanta M, Li L, Godbout R, Weinfeld M, Ismail IH. CDK-Dependent Phosphorylation Regulates PNKP Function in DNA Replication. J Biol Chem 2024:107880. [PMID: 39395804 DOI: 10.1016/j.jbc.2024.107880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 09/24/2024] [Accepted: 09/27/2024] [Indexed: 10/14/2024] Open
Abstract
Okazaki fragment maturation (OFM) stands as a pivotal DNA metabolic process, crucial for genome integrity and cell viability. Dysregulation of OFM leads to DNA single-strand breaks- accumulation, which is linked to various human diseases such as cancer and neurodegenerative disorders. Recent studies have implicated LIG3-XRCC1 acting in an alternative OFM pathway to the canonical FEN1-LIG1 pathway. Here, we reveal that polynucleotide kinase-phosphatase (PNKP) is another key participant in DNA replication, akin to LIG3-XRCC1. Through functional experiments, we demonstrate PNKP's enrichment at DNA replication forks and its association with PCNA, indicating its involvement in replication processes. Cellular depletion of PNKP mirrors defects observed in OFM-related proteins, highlighting its significance in replication fork dynamics. Additionally, we identify PNKP as a substrate for cyclin-dependent kinase 1/2 (CDK1/2), which phosphorylates PNKP at multiple residues. Mutation analysis of these phosphorylation sites underscores the importance of CDK2-mediated PNKP phosphorylation in DNA replication. Our findings collectively indicate a novel role for PNKP in facilitating Okazaki fragment joining, thus shedding light on its contribution to genome stability maintenance.
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Affiliation(s)
- Fatemeh Mashayekhi
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Elham Zeinali
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Cassandra Ganje
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Mesfin Fanta
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Lei Li
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Roseline Godbout
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Michael Weinfeld
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada
| | - Ismail Hassan Ismail
- Division of Experimental Oncology, Department of Oncology, Faculty of Medicine & Dentistry, University of Alberta, 11560 University Avenue, Edmonton, Alberta, Canada; Biophysics Department, Faculty of Science, Cairo University, 12613 Giza, Egypt.
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2
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P P, Kumari S, Kumar S, Muthuswamy S. Comprehensive exploration on the role of base excision repair genes in modulating immune infiltration in low-grade glioma. Pathol Res Pract 2024; 262:155559. [PMID: 39216321 DOI: 10.1016/j.prp.2024.155559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 08/11/2024] [Accepted: 08/23/2024] [Indexed: 09/04/2024]
Abstract
INTRODUCTION Glioma is a brain tumour occurring in all age groups but common in adults. Despite advances in the understanding of tumours, we cannot improve the survival of the patients and do not have an appropriate biomarker for progression and prognosis prediction. The base excision repair mechanism maintains the integrity of the genome, preventing tumour formation. However, continuous chemical damage to the cells results in mutations that escape the repair mechanism and support tumour growth. The tumour microenvironment in cancer is crucial in determining the tumour growth, development, and response to treatments. The present study explored the significance of Base Excision Repair genes (BER) in modulating the tumour microenvironment. METHODS We used the publically available data sets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to explore the role of the base excision repair gene in the modulating tumour microenvironment. The data was analysed for the expression of base excision repair genes, their correlation with the immune markers, their prognostic potential, and enrichment analysis to understand the pathways they modulate in low-grade glioma (LGG) progression. RESULTS The analysis showed BER genes contribute an integral role in the overall and disease-free survival of LGG. Genes like MUTYH, PNKP, UNG and XRCC1 showed a correlation with the immune infiltration levels and a significant correlation with various immune markers associated with different immune cells, including tumour-associated macrophages. MUTYH, UNG and XRCC1 correlated with IDH1 mutation status, and functional enrichment analysis showed that these genes are enriched in several pathways like Wnt, PD-1 and Integrin signalling. CONCLUSION Our findings suggest that the BER genes MUTYH, PNKP, UNG and XRCC1 can potentially be prognostic biomarkers and highly correlate with the immune cells of the tumour microenvironment.
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Affiliation(s)
- Parthipan P
- Human Molecular Genetics Lab, Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India
| | - Subhadra Kumari
- Human Molecular Genetics Lab, Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India
| | - Santosh Kumar
- RNA Biology Lab, Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India
| | - Srinivasan Muthuswamy
- Human Molecular Genetics Lab, Department of Life Science, National Institute of Technology Rourkela, Odisha 769008, India.
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3
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Su A, Luo D, Li S, Zhang Y, Wang H, Yang L, Yang W, Pang P. An electrochemical biosensor for T4 polynucleotide kinase activity assay based on host-guest recognition between phosphate pillar[5]arene@MWCNTs and thionine. Analyst 2024; 149:1271-1279. [PMID: 38226548 DOI: 10.1039/d3an01863f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
T4 polynucleotide kinase helps with DNA recombination and repair. In this study, an electrochemical biosensor was developed for a T4 polynucleotide kinase activity assay and inhibitor screening based on phosphate pillar[5]arene and multi-walled carbon nanotube nanocomposites. The water-soluble pillar[5]arene was employed as the host to complex thionine guest molecules. The substrate DNA with a 5'-hydroxyl group initially self-assembled on the gold electrode surface through chemical adsorption of the thiol group, which was phosphorylated in the presence of T4 polynucleotide kinase. Titanium dioxide nanoparticles served as a bridge to link phosphorylated DNA and phosphate pillar[5]arene and multi-walled carbon nanotube composite due to strong phosphate-Ti4+-phosphate chemistry. Through supramolecular host-guest recognition, thionine molecules were able to penetrate the pillar[5]arene cavity, resulting in an enhanced electrochemical response signal. The electrochemical signal is proportional to the T4 polynucleotide kinase concentration in the range of 10-5 to 15 U mL-1 with a detection limit of 5 × 10-6 U mL-1. It was also effective in measuring HeLa cell lysate-related T4 polynucleotide kinase activity and inhibitor screening. The proposed method offers a unique sensing platform for kinase activity measurement, holding great potential in nucleotide kinase-target drug development, clinical diagnostics, and inhibitor screening.
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Affiliation(s)
- Aiwen Su
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Dan Luo
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Shixuan Li
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Yanli Zhang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Hongbin Wang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Lijuan Yang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
| | - Wenrong Yang
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC 3217, Australia
| | - Pengfei Pang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming 650504, P. R. China.
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4
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Luo D, Liu Z, Su A, Zhang Y, Wang H, Yang L, Yang W, Pang P. An electrochemical biosensor for detection of T4 polynucleotide kinase activity based on host-guest recognition between phosphate pillar[5]arene and methylene blue. Talanta 2024; 266:124956. [PMID: 37499362 DOI: 10.1016/j.talanta.2023.124956] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 07/12/2023] [Accepted: 07/15/2023] [Indexed: 07/29/2023]
Abstract
T4 polynucleotide kinase (T4 PNK) is an important DNA repair-related enzyme that plays a crucial role in DNA recombination, replication and damage repair. Herein, an electrochemical biosensor was developed for detection of T4 PNK activity and inhibitor screening based on supramolecular host-guest recognition between phosphate pillar (Dumitrache and McKinnon, 2017) [5] arene (PP5) and methylene blue (MB). The water-soluble PP5 employed as the host for complexation of MB guest molecules. The substrate DNA with 5'-hydroxyl group was first self-assembled on the gold electrode surface through the chemical adsorption of the thiol group, which was phosphorylated in the presence of T4 PNK and adenosine triphosphate (ATP). TiO2 served as a bridge to link phosphorylated DNA and PP5 via the robust phosphate-Ti4+-phosphate chemistry. The immobilized PP5 captured the MB on electrode surface via the supramolecular host-guest recognition interaction, resulting in an enhanced electrochemical response signal. The electrochemical signal is proportional to the T4 PNK concentration in the range of 2 × 10-4 to 5 U mL-1 with a detection limit of 1 × 10-4 U mL-1. It was also successfully used for PNK inhibitor screening and PNK activity assay in HeLa cell lysates sample. The proposed strategy provides a novel sensing platform for kinase activity assay and inhibitor screening, holding a great potential in clinical diagnostics, inhibitor screening, and nucleotide kinase-target drug discovery.
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Affiliation(s)
- Dan Luo
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China
| | - Zaiqiong Liu
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China
| | - Aiwen Su
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China
| | - Yanli Zhang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China.
| | - Hongbin Wang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China
| | - Lijuan Yang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China.
| | - Wenrong Yang
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, 3217, Australia
| | - Pengfei Pang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, PR China.
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5
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Thuresson A, Brazina J, Akram T, Albrecht J, Dahl N, Soussi Zander C, Caldecott KW. Novel PNKP mutations associated with reduced DNA single-strand break repair and severe microcephaly, seizures, and developmental delay. Mol Genet Genomic Med 2024; 12:e2295. [PMID: 37916443 PMCID: PMC10767416 DOI: 10.1002/mgg3.2295] [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: 03/16/2023] [Revised: 08/18/2023] [Accepted: 09/19/2023] [Indexed: 11/03/2023] Open
Abstract
BACKGROUND Microcephaly with early-onset seizures (MCSZ) is a neurodevelopmental disorder caused by pathogenic variants in the DNA strand break repair protein, polynucleotide kinase 3'-phosphatase (PNKP). METHODS We have used whole genome sequencing and Sanger sequencing to identify disease-causing variants, followed by a minigene assay, Western blotting, alkaline comet assay, γH2AX, and ADP-ribose immunofluorescence. RESULTS Here, we describe a patient with compound heterozygous variants in PNKP, including a missense variant in the DNA phosphatase domain (T323M) and a novel splice acceptor site variant within the DNA kinase domain that we show leads to exon skipping. We show that primary fibroblasts derived from the patient exhibit greatly reduced levels of PNKP protein and reduced rates of DNA single-strand break repair, confirming that the mutated PNKP alleles are dysfunctional. CONCLUSION The data presented show that the detected compound heterozygous variants result in reduced levels of PNKP protein, which affect the repair of both oxidative and TOP1-induced single-strand breaks, and most likely causes MCSZ in this patient.
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Affiliation(s)
- Ann‐Charlotte Thuresson
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory UppsalaUppsala UniversityUppsalaSweden
| | - Jan Brazina
- Genome Damage and Stability CentreUniversity of SussexBrightonUK
| | - Talia Akram
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory UppsalaUppsala UniversityUppsalaSweden
- Present address:
Departments of Pediatrics, Neurology and PhysiologyNorthwestern University Feinberg School of Medicine, Ann & Robert H. Lurie Children's Hospital of ChicagoChicagoIllinoisUSA
| | | | - Niklas Dahl
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory UppsalaUppsala UniversityUppsalaSweden
| | - Cecilia Soussi Zander
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory UppsalaUppsala UniversityUppsalaSweden
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Wu Y, Yi J, Su A, Zhang Y, Wang H, Yang L, Yang W, Pang P. An electrochemical biosensor for T4 polynucleotide kinase activity identification according to host-guest recognition among phosphate pillar[5]arene@palladium nanoparticles@reduced graphene oxide nanocomposite and toluidine blue. Mikrochim Acta 2023; 190:394. [PMID: 37715009 DOI: 10.1007/s00604-023-05983-w] [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: 06/11/2023] [Accepted: 09/02/2023] [Indexed: 09/17/2023]
Abstract
T4 polynucleotide kinase (T4 PNK) helps with DNA recombination and repair. In this work, a phosphate pillar[5]arene@palladium nanoparticles@reduced graphene oxide nanocomposite (PP5@PdNPs@rGO)-based electrochemical biosensor was created to identify T4 PNK activities. The PP5 used to complex toluidine blue (TB) guest molecules is water-soluble. With T4 PNK and ATP, the substrate DNA, which included a 5'-hydroxyl group, initially self-assembled over the gold electrode surface by chemical adsorption of the thiol units. Strong phosphate-Zr4+-phosphate chemistry allowed Zr4+ to act as a bridge between phosphorylated DNA and PP5@PdNPs@rGO. Through a supramolecular host-guest recognition connection, TB molecules were able to penetrate the PP5 cavity, where they produced a stronger electrochemical response. With a 5 × 10-7 U mL-1 detection limit, the electrochemical signal is linear in the 10-6 to 1 U mL-1 T4 PNK concentration range. It was also effective in measuring HeLa cell lysate-related PNK activities and screening PNK inhibitors. Nucleotide kinase-target drug development, clinical diagnostics, and screening for inhibitors all stand to benefit greatly from the suggested technology, which offers a unique sensing mechanism for kinase activity measurement.
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Affiliation(s)
- Yongju Wu
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
| | - Jinfei Yi
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
| | - Aiwen Su
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
| | - Yanli Zhang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China.
| | - Hongbin Wang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
| | - Lijuan Yang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
| | - Wenrong Yang
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, 3217, Australia
| | - Pengfei Pang
- Key Laboratory of Environmental Functional Materials of Yunnan Province Education Department, Yunnan Minzu University, Kunming, 650504, People's Republic of China
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7
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Islam A, Chakraborty A, Gambardella S, Campopiano R, Sarker AH, Boldogh I, Hazra T. Functional analysis of a conserved site mutation in the DNA end processing enzyme PNKP leading to ataxia with oculomotor apraxia type 4 in humans. J Biol Chem 2023; 299:104714. [PMID: 37061005 PMCID: PMC10197107 DOI: 10.1016/j.jbc.2023.104714] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/06/2023] [Accepted: 04/07/2023] [Indexed: 04/17/2023] Open
Abstract
Polynucleotide kinase 3'-phosphatase (PNKP), an essential DNA end-processing enzyme in mammals with 3'-phosphatase and 5'-kinase activities, plays a pivotal role in multiple DNA repair pathways. Its functional deficiency has been etiologically linked to various neurological disorders. Recent reports have shown that mutation at a conserved glutamine (Gln) in PNKP leads to late-onset ataxia with oculomotor apraxia type 4 (AOA4) in humans and embryonic lethality in pigs. However, the molecular mechanism underlying such phenotypes remains elusive. Here, we report that the enzymatic activities of the mutant versus WT PNKP are comparable; however, cells expressing mutant PNKP and peripheral blood mononuclear cells (PBMCs) of AOA4 patients showed a significant amount of DNA double-strand break accumulation and consequent activation of the DNA damage response. Further investigation revealed that the nuclear localization of mutant PNKP is severely abrogated, and the mutant proteins remain primarily in the cytoplasm. Western blot analysis of AOA4 patient-derived PBMCs also revealed the presence of mutated PNKP predominantly in the cytoplasm. To understand the molecular determinants, we identified that mutation at a conserved Gln residue impedes the interaction of PNKP with importin alpha but not with importin beta, two highly conserved proteins that mediate the import of proteins from the cytoplasm into the nucleus. Collectively, our data suggest that the absence of PNKP in the nucleus leads to constant activation of the DNA damage response due to persistent accumulation of double-strand breaks in the mutant cells, triggering death of vulnerable brain cells-a potential cause of neurodegeneration in AOA4 patients.
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Affiliation(s)
- Azharul Islam
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Anirban Chakraborty
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA
| | - Stefano Gambardella
- IRCCS Neuromed & Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Rosa Campopiano
- IRCCS Neuromed & Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Altaf H Sarker
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Istvan Boldogh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Tapas Hazra
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas, USA.
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8
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An enzyme-free and label-free electrochemical biosensor for polynucleotide kinase. Talanta 2023. [DOI: 10.1016/j.talanta.2022.124004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Construction of a simple, localized and homogeneous fluorescence detection platform for T4 PNK activity based on tetrahedral DNA nanostructure-mediated primer exchange reaction. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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10
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Zhang Q, Zhang X, Ma F, Zhang CY. Advances in quantum dot-based biosensors for DNA-modifying enzymes assay. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2022.214674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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11
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Jia D, Fan W, Ren W, Liu C. One-step detection of T4 polynucleotide kinase activity based on single particle-confined enzyme reaction and digital particle counting. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Bayram N, Yaman Y, Elli M, Ozdilli K, Nepesov S, Dogan MS, Ayaz A, Anak S. HLA - matched related donor hematopoietic stem cell transplantation in a patient with polynucleotide kinase 3-phosphatase mutation developed acute myeloid leukemia. Pediatr Transplant 2022; 26:e14255. [PMID: 35187769 DOI: 10.1111/petr.14255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 01/27/2022] [Accepted: 02/07/2022] [Indexed: 12/31/2022]
Abstract
BACKGROUND PNPK gene mutations result in DNA repair disorders and have a spectrum of neurodevelopmental manifestations. To date, cancer predisposition has not been described in patients with PNKP mutations. OBSERVATION Here, we report a patient with PNKP mutation, who developed AML at age of five and underwent reduced-intensity HSCT. CONCLUSION Although many DNA repair disorders are known to have increased risk of malignancy, association between PNKP mutations and malignancy is not well-described. This report is the first description of a PNPK mutation patient developing a malignancy and undergoing curative HSCT.
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Affiliation(s)
- Nihan Bayram
- Pediatric Hematology and Oncology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Yontem Yaman
- Pediatric Hematology and Oncology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Murat Elli
- Pediatric Hematology and Oncology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Kursat Ozdilli
- Medical Biology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Serdar Nepesov
- Immunology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Mehmet Sait Dogan
- Pediatric Radiology Department, Istanbul Medipol University, Istanbul, Turkey
| | - Akif Ayaz
- Genetics Department, Istanbul Medipol University, Istanbul, Turkey
| | - Sema Anak
- Pediatric Hematology and Oncology Department, Istanbul Medipol University, Istanbul, Turkey
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Lu H, Guan J, Wang SY, Li GM, Bohr VA, Davis AJ. DNA-PKcs-dependent phosphorylation of RECQL4 promotes NHEJ by stabilizing the NHEJ machinery at DNA double-strand breaks. Nucleic Acids Res 2022; 50:5635-5651. [PMID: 35580045 PMCID: PMC9178012 DOI: 10.1093/nar/gkac375] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 04/25/2022] [Accepted: 05/03/2022] [Indexed: 12/21/2022] Open
Abstract
Non-homologous end joining (NHEJ) is the major pathway that mediates the repair of DNA double-strand breaks (DSBs) generated by ionizing radiation (IR). Previously, the DNA helicase RECQL4 was implicated in promoting NHEJ, but its role in the pathway remains unresolved. In this study, we report that RECQL4 stabilizes the NHEJ machinery at DSBs to promote repair. Specifically, we find that RECQL4 interacts with the NHEJ core factor DNA-PKcs and the interaction is increased following IR. RECQL4 promotes DNA end bridging mediated by DNA-PKcs and Ku70/80 in vitro and the accumulation/retention of NHEJ factors at DSBs in vivo. Moreover, interaction between DNA-PKcs and the other core NHEJ proteins following IR treatment is attenuated in the absence of RECQL4. These data indicate that RECQL4 promotes the stabilization of the NHEJ factors at DSBs to support formation of the NHEJ long-range synaptic complex. In addition, we observed that the kinase activity of DNA-PKcs is required for accumulation of RECQL4 to DSBs and that DNA-PKcs phosphorylates RECQL4 at six serine/threonine residues. Blocking phosphorylation at these sites reduced the recruitment of RECQL4 to DSBs, attenuated the interaction between RECQL4 and NHEJ factors, destabilized interactions between the NHEJ machinery, and resulted in decreased NHEJ. Collectively, these data illustrate reciprocal regulation between RECQL4 and DNA-PKcs in NHEJ.
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Affiliation(s)
- Huiming Lu
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Junhong Guan
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shih-Ya Wang
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Guo-Min Li
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Vilhelm A Bohr
- DNA Repair Section, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Anthony J Davis
- Department of Radiation Oncology, UT Southwestern Medical Center, Dallas, TX 75390, USA
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14
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Ali A, Xiao W, Babar ME, Bi Y. Double-Stranded Break Repair in Mammalian Cells and Precise Genome Editing. Genes (Basel) 2022; 13:genes13050737. [PMID: 35627122 PMCID: PMC9142082 DOI: 10.3390/genes13050737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 12/16/2022] Open
Abstract
In mammalian cells, double-strand breaks (DSBs) are repaired predominantly by error-prone non-homologous end joining (NHEJ), but less prevalently by error-free template-dependent homologous recombination (HR). DSB repair pathway selection is the bedrock for genome editing. NHEJ results in random mutations when repairing DSB, while HR induces high-fidelity sequence-specific variations, but with an undesirable low efficiency. In this review, we first discuss the latest insights into the action mode of NHEJ and HR in a panoramic view. We then propose the future direction of genome editing by virtue of these advancements. We suggest that by switching NHEJ to HR, full fidelity genome editing and robust gene knock-in could be enabled. We also envision that RNA molecules could be repurposed by RNA-templated DSB repair to mediate precise genetic editing.
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Affiliation(s)
- Akhtar Ali
- Key Laboratory of Animal Embryo and Molecular Breeding of Hubei Province, Institute of Animal Science and Veterinary Medicine, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; (A.A.); (W.X.)
- Department of Biotechnology, Virtual University of Pakistan, Lahore 54000, Pakistan
| | - Wei Xiao
- Key Laboratory of Animal Embryo and Molecular Breeding of Hubei Province, Institute of Animal Science and Veterinary Medicine, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; (A.A.); (W.X.)
| | - Masroor Ellahi Babar
- The University of Agriculture Dera Ismail Khan, Dera Ismail Khan 29220, Pakistan;
| | - Yanzhen Bi
- Key Laboratory of Animal Embryo and Molecular Breeding of Hubei Province, Institute of Animal Science and Veterinary Medicine, Hubei Academy of Agricultural Sciences, Wuhan 430064, China; (A.A.); (W.X.)
- Correspondence: ; Tel.: +86-151-0714-8708
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15
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Jiang B, Murray C, Cole BL, Glover JNM, Chan GK, Deschenes J, Mani RS, Subedi S, Nerva JD, Wang AC, Lockwood CM, Mefford HC, Leary SES, Ojemann JG, Weinfeld M, Ene CI. Mutations of the DNA repair gene PNKP in a patient with microcephaly, seizures, and developmental delay (MCSZ) presenting with a high-grade brain tumor. Sci Rep 2022; 12:5386. [PMID: 35354845 PMCID: PMC8967877 DOI: 10.1038/s41598-022-09097-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 03/04/2022] [Indexed: 11/08/2022] Open
Abstract
Polynucleotide Kinase-Phosphatase (PNKP) is a bifunctional enzyme that possesses both DNA 3'-phosphatase and DNA 5'-kinase activities, which are required for processing termini of single- and double-strand breaks generated by reactive oxygen species (ROS), ionizing radiation and topoisomerase I poisons. Even though PNKP is central to DNA repair, there have been no reports linking PNKP mutations in a Microcephaly, Seizures, and Developmental Delay (MSCZ) patient to cancer. Here, we characterized the biochemical significance of 2 germ-line point mutations in the PNKP gene of a 3-year old male with MSCZ who presented with a high-grade brain tumor (glioblastoma multiforme) within the cerebellum. Functional and biochemical studies demonstrated these PNKP mutations significantly diminished DNA kinase/phosphatase activities, altered its cellular distribution, caused defective repair of DNA single/double stranded breaks, and were associated with a higher propensity for oncogenic transformation. Our findings indicate that specific PNKP mutations may contribute to tumor initiation within susceptible cells in the CNS by limiting DNA damage repair and increasing rates of spontaneous mutations resulting in pediatric glioma associated driver mutations such as ATRX and TP53.
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Affiliation(s)
- Bingcheng Jiang
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Cameron Murray
- Department of Biochemistry, University of Alberta, Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Bonnie L Cole
- Department of Pathology, University of Washington, Seattle, WA, USA
| | - J N Mark Glover
- Department of Biochemistry, University of Alberta, Medical Sciences Building, Edmonton, AB, T6G 2H7, Canada
| | - Gordon K Chan
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Jean Deschenes
- Department of Laboratory Medicine and Pathology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Rajam S Mani
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - Sudip Subedi
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada
| | - John D Nerva
- Department of Neurological Surgery, Tulane University, New Orleans, LA, USA
| | - Anthony C Wang
- Department of Neurological Surgery, University of California Los Angeles, Los Angeles, CA, USA
| | | | - Heather C Mefford
- Division of Genetics Medicine, University of Washington, Seattle, WA, USA
| | - Sarah E S Leary
- Division of Pediatric Hematology/Oncology, Seattle Children's Hospital, Seattle, WA, USA
| | - Jeffery G Ojemann
- Department of Neurological Surgery, University of Washington, Seattle, WA, USA
| | - Michael Weinfeld
- Department of Oncology, University of Alberta, Cross Cancer Institute, 11560 University Ave., Edmonton, AB, T6G 1Z2, Canada.
| | - Chibawanye I Ene
- Department of Neurological Surgery, MD Anderson Cancer Center, Houston, TX, USA.
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16
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Species variations in XRCC1 recruitment strategies for FHA domain-containing proteins. DNA Repair (Amst) 2022; 110:103263. [PMID: 35026705 PMCID: PMC9282668 DOI: 10.1016/j.dnarep.2021.103263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 11/07/2021] [Accepted: 12/21/2021] [Indexed: 02/03/2023]
Abstract
DNA repair scaffolds XRCC1 and XRCC4 utilize a phosphopeptide FHA domain binding motif (FBM) of the form Y-x-x-pS-pT-D-E that supports recruitment of three identified FHA domain-containing DNA repair proteins: polynucleotide kinase/phosphatase (PNKP), aprataxin (APTX), and a third protein, APLF, that functions as a scaffold in support of non-homologous end joining (NHEJ). Mammalian dimeric XRCC4 is able to interact with two of these proteins at any given time, while monomeric XRCC1 binds only one. However, sequence analysis indicates that amphibian and teleost XRCC1 generally contain two FHA binding motifs. X1-FBM1, is similar to the single mammalian XRCC1 FBM and probably functions similarly. X1-FBM2, is more similar to mammalian XRCC4 FBM; it is located closer to the XRCC1 BRCT1 domain and probably is less discriminating among its three likely binding partners. Availability of an additional PNKP or APTX recruitment motif may alleviate the bottleneck that results from using a single FBM motif for recruitment of multiple repair factors. Alternatively, recruitment of APLF by X1-FBM2 may function to rescue a misdirected or unsuccessful SSB repair response by redirecting the damaged DNA to the NHEJ pathway, - a need that results from the ambiguity of the PARP1 signal regarding the nature of the damage. Evaluation of XRCC4 FBMs in acanthomorphs, which account for a majority of the reported teleost sequences, reveals the presence of an additional XRCC4-like paralog, distinct from other previously described members of the XRCC4 superfamily. The FBM is typically absent in acanthomorph XRCC4, but present in the XRCC4-like paralog. Modeling suggests that XRCC4 and its paralog may form homodimers or XRCC4-XRCC4-like heterodimers.
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17
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Tao J, Liu Z, Zhu Z, Zhang Y, Wang H, Pang P, Yang C, Yang W. Electrochemical detection of T4 polynucleotide kinase activity based on magnetic Fe 3O 4@TiO 2 nanoparticles triggered by a rolling circle amplification strategy. Talanta 2022; 241:123272. [PMID: 35121542 DOI: 10.1016/j.talanta.2022.123272] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/24/2022] [Accepted: 01/27/2022] [Indexed: 12/29/2022]
Abstract
An ultrasensitive electrochemical detection of the activity and inhibition of T4 polynucleotide kinase (T4 PNK) was developed by using magnetic Fe3O4@TiO2 core-shell nanoparticles, which was triggered by a rolling circle amplification strategy (Fe3O4@TiO2-RCA). We used Fe3O4@TiO2 as a substrate to anchor a DNA primer. DNA S1 with 5'-OH termini was phosphorylated in the presence of T4 PNK and ATP, which was adsorbed on the surface of Fe3O4@TiO2 NPs and served as the primer for subsequent RCA reactions. After adding circular template DNA S2, RCA was initiated in the presence of phi29 DNA polymerase and dNTPs. Then, Fc-labeled DNA S3 (Fc-S3) was hybridized with RCA. The obtained Fe3O4@TiO2-RCA was adsorbed on the surface of a magnetic gold electrode (MGE) by magnetic enrichment, resulting in an enhanced electrochemical signal. The T4 PNK activity can be monitored by measuring the electrochemical signal generated. This electrochemical assay is sensitive to the activity of T4 PNK with a dynamic linear range of 0.00001-20 U/mL and a low detection limit of 3.0 × 10-6 U/mL. The proposed strategy can be used to screen the T4 PNK inhibitors, so it has great potential in the discovery of nucleotide kinase-target drug and early clinical diagnosis of cancer.
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Affiliation(s)
- Jinpeng Tao
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China
| | - Zaiqiong Liu
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China
| | - Zhenyu Zhu
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China
| | - Yanli Zhang
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China.
| | - Hongbin Wang
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China
| | - Pengfei Pang
- National and Local Joint Engineering Research Center for Green Preparation Technology of Biobased Materials, Yunnan Minzu University, Kunming, 650500, PR China.
| | - Chun Yang
- Shaanxi Geological Survey Center, Xi'an, 710068, PR China
| | - Wenrong Yang
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, 3217, Australia
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18
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Sadat SMA, Wuest M, Paiva IM, Munira S, Sarrami N, Sanaee F, Yang X, Paladino M, Binkhathlan Z, Karimi-Busheri F, Martin GR, Jirik FR, Murray D, Gamper AM, Hall DG, Weinfeld M, Lavasanifar A. Nano-Delivery of a Novel Inhibitor of Polynucleotide Kinase/Phosphatase (PNKP) for Targeted Sensitization of Colorectal Cancer to Radiation-Induced DNA Damage. Front Oncol 2022; 11:772920. [PMID: 35004293 PMCID: PMC8733593 DOI: 10.3389/fonc.2021.772920] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 11/24/2021] [Indexed: 12/29/2022] Open
Abstract
Inhibition of the DNA repair enzyme polynucleotide kinase/phosphatase (PNKP) increases the sensitivity of cancer cells to DNA damage by ionizing radiation (IR). We have developed a novel inhibitor of PNKP, i.e., A83B4C63, as a potential radio-sensitizer for the treatment of solid tumors. Systemic delivery of A83B4C63, however, may sensitize both cancer and normal cells to DNA damaging therapeutics. Preferential delivery of A83B4C63 to solid tumors by nanoparticles (NP) was proposed to reduce potential side effects of this PNKP inhibitor to normal tissue, particularly when combined with DNA damaging therapies. Here, we investigated the radio-sensitizing activity of A83B4C63 encapsulated in NPs (NP/A83) based on methoxy poly(ethylene oxide)-b-poly(α-benzyl carboxylate-ε-caprolactone) (mPEO-b-PBCL) or solubilized with the aid of Cremophor EL: Ethanol (CE/A83) in human HCT116 colorectal cancer (CRC) models. Levels of γ-H2AX were measured and the biodistribution of CE/A83 and NP/A83 administered intravenously was determined in subcutaneous HCT116 CRC xenografts. The radio-sensitization effect of A83B4C63 was measured following fractionated tumor irradiation using an image-guided Small Animal Radiation Research Platform (SARRP), with 24 h pre-administration of CE/A83 and NP/A83 to Luc+/HCT116 bearing mice. Therapeutic effects were analyzed by monitoring tumor growth and functional imaging using Positron Emission Tomography (PET) and [18F]-fluoro-3’-deoxy-3’-L:-fluorothymidine ([18F]FLT) as a radiotracer for cell proliferation. The results showed an increased persistence of DNA damage in cells treated with a combination of CE/A83 or NP/A83 and IR compared to those only exposed to IR. Significantly higher tumor growth delay in mice treated with a combination of IR and NP/A83 than those treated with IR plus CE/A83 was observed. [18F]FLT PET displayed significant functional changes for tumor proliferation for the drug-loaded NP. This observation was attributed to the higher A83B4C63 levels in the tumors for NP/A83-treated mice compared to those treated with CE/A83. Overall, the results demonstrated a potential for A83B4C63-loaded NP as a novel radio-sensitizer for the treatment of CRC.
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Affiliation(s)
- Sams M A Sadat
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Melinda Wuest
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Igor M Paiva
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Sirazum Munira
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Nasim Sarrami
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Forughalsadat Sanaee
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada
| | - Xiaoyan Yang
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Marco Paladino
- Department of Chemistry, Faculty of Science, University of Alberta, Edmonton, AB, Canada
| | - Ziyad Binkhathlan
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada.,Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Feridoun Karimi-Busheri
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Gary R Martin
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Frank R Jirik
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada.,Department of Medicine, University of Calgary, Calgary, AB, Canada
| | - David Murray
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Armin M Gamper
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Dennis G Hall
- Department of Chemistry, Faculty of Science, University of Alberta, Edmonton, AB, Canada
| | - Michael Weinfeld
- Department of Oncology, Cross Cancer Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Afsaneh Lavasanifar
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, AB, Canada.,Department of Chemical and Material Engineering, University of Alberta, Edmonton, AB, Canada
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19
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Zhao L, Chen Y, Wu X, Li Z, Dong Y, Wang GL. Invoking Cathodic Photoelectrochemistry through a Spontaneously Coordinated Electron Transporter: A Proof of Concept Toward Signal Transduction for Bioanalysis. Anal Chem 2021; 93:17119-17126. [PMID: 34908413 DOI: 10.1021/acs.analchem.1c04750] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Most of the cathodic photoelectrochemical (PEC) bioassays rely on electron accepting molecules for signal stimuli; unfortunately, the performances of which are still undesirable. New signal transduction strategies are still highly expected for the further development of cathodic photoelectrochemistry as a potentially competitive method. This work represents a new concept of invoked cathodic photoelectrochemistry by a spontaneously formed electron transporter for innovative operation of the sensing strategy. Specifically, the hexacyanoferrate(II) in solution easily self-coordinated with CuO nanomaterials and formed electron transporting copper hexacyanoferrate (CuHCF) on the surface, which endowed improved carrier separation for presenting augmented photocurrent readout. Exemplified by the T4 polynucleotide kinase (T4 PNK) and its inhibitors as targets, a homogenous cathodic PEC biosensing platform was achieved with the distinctive merits of label-free, immobilization-free, and split-mode readout. The mechanism revealed here provided a totally different perspective for signal transduction in cathodic photoelectrochemistry. Hopefully, it may stimulate more interests in the design and construction of semiconductor/transporter counterparts for exquisite operation of photocathodic bioanalysis.
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Affiliation(s)
- Lingling Zhao
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Yanru Chen
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Xiuming Wu
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Zaijun Li
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Yuming Dong
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China
| | - Guang-Li Wang
- Key Laboratory of Synthetic and Biological Colloids (Ministry of Education), School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China.,Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
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20
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Ma F, Li CC, Zhang CY. Nucleic acid amplification-integrated single-molecule fluorescence imaging for in vitro and in vivo biosensing. Chem Commun (Camb) 2021; 57:13415-13428. [PMID: 34796887 DOI: 10.1039/d1cc04799j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Single-molecule fluorescence imaging is among the most advanced analytical technologies and has been widely adopted for biosensing due to its distinct advantages of simplicity, rapidity, high sensitivity, low sample consumption, and visualization capability. Recently, a variety of nucleic acid amplification approaches have been developed to provide a straightforward and highly efficient way for amplifying low abundance target signals. The integration of single-molecule fluorescence imaging with nucleic acid amplification has greatly facilitated the construction of various fluorescent biosensors for in vitro and in vivo detection of DNAs, RNAs, enzymes, and live cells with high sensitivity and good selectivity. Herein, we review the advances in the development of fluorescent biosensors by integrating single-molecule fluorescence imaging with nucleic acid amplification based on enzyme (e.g., DNA polymerase, RNA polymerase, exonuclease, and endonuclease)-assisted and enzyme-free (e.g., catalytic hairpin assembly, entropy-driven DNA amplification, ligation chain reaction, and hybridization chain reaction) strategies, and summarize the principles, features, and in vitro and in vivo applications of the emerging biosensors. Moreover, we discuss the remaining challenges and future directions in this area. This review may inspire the development of new signal-amplified single-molecule biosensors and promote their practical applications in fundamental and clinical research.
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Affiliation(s)
- Fei Ma
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China. .,School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189, China.
| | - Chen-Chen Li
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China. .,Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Chun-Yang Zhang
- Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China.
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21
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Zhang L, Fan W, Jia D, Feng Q, Ren W, Liu C. Microchamber-Free Digital Flow Cytometric Analysis of T4 Polynucleotide Kinase Phosphatase Based on Single-Enzyme-to-Single-Bead Space-Confined Reaction. Anal Chem 2021; 93:14828-14836. [PMID: 34713697 DOI: 10.1021/acs.analchem.1c03724] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Digital bioassays have attracted extensive attention in biomedical applications due to their ultrahigh sensitivity. However, traditional digital bioassays require numerous microchambers such as droplets or microwells, which restricts their application scope. Herein, we propose a microchamber-free flow cytometric method for the digital quantification of T4 polynucleotide kinase phosphatase (T4 PNKP) based on an unprecedented phenomenon that each T4 PNKP molecule-catalyzed reaction can be spatially self-confined on a single microbead, which ultimately enables the one-target-to-one-fluorescence-positive microbead digital signal transduction. The digital signal-readout mode can clearly detect T4 PNKP concentrations as low as 1.28 × 10-10 U/μL, making it most sensitive method to date. Significantly, T4 PNKP can be specifically distinguished from other phosphatases and nucleases in complex samples by digitally counting the fluorescence-positive microbeads, which cannot be realized by traditional bulk measurement-based methods. Taking advantage of the novel space-confined enzymatic feature of T4 PNKP, this digital mechanism can use T4 PNKP as the enzyme label to fabricate digital sensing systems toward various biomolecules such as digital enzyme-linked immunosorbent assay (ELISA). Therefore, this work not only enlarges the toolbox for high-sensitivity biomolecule detection but also opens new gates to fabricate next-generation digital assays.
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Affiliation(s)
- Lijun Zhang
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
| | - Wenjiao Fan
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
| | - Dailu Jia
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
| | - Qinya Feng
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
| | - Wei Ren
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
| | - Chenghui Liu
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education; Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province; School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an 710119, Shaanxi Province, P. R. China
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22
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Discovery of potential inhibitors targeting the kinase domain of polynucleotide kinase/phosphatase (PNKP): Homology modeling, virtual screening based on multiple conformations, and molecular dynamics simulation. Comput Biol Chem 2021; 94:107517. [PMID: 34456161 DOI: 10.1016/j.compbiolchem.2021.107517] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/11/2021] [Accepted: 05/16/2021] [Indexed: 12/15/2022]
Abstract
In recent years, the level of interest has been increased in developing the DNA-repair inhibitors, to enhance the cytotoxic effects in the treatment of cancers. Polynucleotide kinase/phosphatase (PNKP) is a critical human DNA repair enzyme that repairs DNA strand breaks by catalyzing the restoration of 5'-phosphate and 3'-hydroxyl termini that are required for subsequent processing by DNA ligases and polymerases. PNKP is the only protein that repairs the 3'-hydroxyl group and 5'-phosphate group, which depicts PNKP as a potential therapeutic target. Besides, PNKP is the only DNA-repair enzyme that contains the 5'-kinase activity, therefore, targeting this kinase domain would motivate the development of novel PNKP-specific inhibitors. However, there are neither crystal structures of human PNKP nor the kinase inhibitors reported so far. Thus, in this present study, a sequential molecular docking-based virtual screening with multiple PNKP conformations integrating homology modeling, molecular dynamics simulation, and binding free energy calculation was developed to discover novel PNKP kinase inhibitors, and the top-scored molecule was finally submitted to molecular dynamics simulation to reveal the binding mechanism between the inhibitor and PNKP. Taken together, the current study could provide some guidance for the molecular docking based-virtual screening of novel PNKP kinase inhibitors.
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23
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Guha S, Bhaumik SR. Transcription-coupled DNA double-strand break repair. DNA Repair (Amst) 2021; 109:103211. [PMID: 34883263 DOI: 10.1016/j.dnarep.2021.103211] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 08/11/2021] [Accepted: 08/11/2021] [Indexed: 12/20/2022]
Abstract
The genomic DNA is constantly under attack by cellular and/or environmental factors. Fortunately, the cell is armed to safeguard its genome by various mechanisms such as nucleotide excision, base excision, mismatch and DNA double-strand break repairs. While these processes maintain the integrity of the genome throughout, DNA repair occurs preferentially faster at the transcriptionally active genes. Such transcription-coupled repair phenomenon plays important roles to maintain active genome integrity, failure of which would interfere with transcription, leading to an altered gene expression (and hence cellular pathologies/diseases). Among the various DNA damages, DNA double-strand breaks are quite toxic to the cells. If DNA double-strand break occurs at the active gene, it would interfere with transcription/gene expression, thus threatening cellular viability. Such DNA double-strand breaks are found to be repaired faster at the active gene in comparison to its inactive state or the inactive gene, thus supporting the existence of a new phenomenon of transcription-coupled DNA double-strand break repair. Here, we describe the advances of this repair process.
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Affiliation(s)
- Shalini Guha
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL, 62901, USA
| | - Sukesh R Bhaumik
- Department of Biochemistry and Molecular Biology, Southern Illinois University School of Medicine, Carbondale, IL, 62901, USA.
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24
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Shin W, Alpaugh W, Hallihan LJ, Sinha S, Crowther E, Martin GR, Scheidl-Yee T, Yang X, Yoon G, Goldsmith T, Berger ND, de Almeida LG, Dufour A, Dobrinski I, Weinfeld M, Jirik FR, Biernaskie J. PNKP is required for maintaining the integrity of progenitor cell populations in adult mice. Life Sci Alliance 2021; 4:4/9/e202000790. [PMID: 34226276 PMCID: PMC8321660 DOI: 10.26508/lsa.202000790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 11/24/2022] Open
Abstract
Knockout of Pnkp in adult mice impairs the growth of hair follicle, spermatogonial, and neural progenitor populations. DNA repair proteins are critical to the maintenance of genomic integrity. Specific types of genotoxic factors, including reactive oxygen species generated during normal cellular metabolism or as a result of exposure to exogenous oxidative agents, frequently leads to “ragged” single-strand DNA breaks. The latter exhibits abnormal free DNA ends containing either a 5′-hydroxyl or 3′-phosphate requiring correction by the dual function enzyme, polynucleotide kinase phosphatase (PNKP), before DNA polymerase and ligation reactions can occur to seal the break. Pnkp gene deletion during early murine development leads to lethality; in contrast, the role of PNKP in adult mice is unknown. To investigate the latter, we used an inducible conditional mutagenesis approach to cause global disruption of the Pnkp gene in adult mice. This resulted in a premature aging-like phenotype, characterized by impaired growth of hair follicles, seminiferous tubules, and neural progenitor cell populations. These results point to an important role for PNKP in maintaining the normal growth and survival of these murine progenitor populations.
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Affiliation(s)
- Wisoo Shin
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Whitney Alpaugh
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Laura J Hallihan
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Sarthak Sinha
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Emilie Crowther
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Gary R Martin
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | | | - Xiaoyan Yang
- Department of Oncology, University of Alberta, and Cross Cancer Institute, Edmonton, Canada
| | - Grace Yoon
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Taylor Goldsmith
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Nelson D Berger
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Luiz Gn de Almeida
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Antoine Dufour
- McCaig Institute for Bone and Joint Health, Calgary, Canada.,Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada.,Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada
| | - Ina Dobrinski
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada
| | - Michael Weinfeld
- Department of Oncology, University of Alberta, and Cross Cancer Institute, Edmonton, Canada
| | - Frank R Jirik
- McCaig Institute for Bone and Joint Health, Calgary, Canada .,Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada.,Alberta Children's Hospital Research Institute, Calgary, Canada
| | - Jeff Biernaskie
- Department of Comparative Biology and Experimental Medicine, University of Calgary, Calgary, Canada .,Department of Physiology and Pharmacology, University of Calgary, Calgary, Canada.,Department of Surgery, University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, Calgary, Canada
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25
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Xue C, Greene EC. DNA Repair Pathway Choices in CRISPR-Cas9-Mediated Genome Editing. Trends Genet 2021; 37:639-656. [PMID: 33896583 PMCID: PMC8187289 DOI: 10.1016/j.tig.2021.02.008] [Citation(s) in RCA: 133] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 12/14/2022]
Abstract
Many clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9)-based genome editing technologies take advantage of Cas nucleases to induce DNA double-strand breaks (DSBs) at desired locations within a genome. Further processing of the DSBs by the cellular DSB repair machinery is then necessary to introduce desired mutations, sequence insertions, or gene deletions. Thus, the accuracy and efficiency of genome editing are influenced by the cellular DSB repair pathways. DSBs are themselves highly genotoxic lesions and as such cells have evolved multiple mechanisms for their repair. These repair pathways include homologous recombination (HR), classical nonhomologous end joining (cNHEJ), microhomology-mediated end joining (MMEJ) and single-strand annealing (SSA). In this review, we briefly highlight CRISPR-Cas9 and then describe the mechanisms of DSB repair. Finally, we summarize recent findings of factors that can influence the choice of DNA repair pathway in response to Cas9-induced DSBs.
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Affiliation(s)
- Chaoyou Xue
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Eric C Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
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26
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Hammel M, Tainer JA. X-ray scattering reveals disordered linkers and dynamic interfaces in complexes and mechanisms for DNA double-strand break repair impacting cell and cancer biology. Protein Sci 2021; 30:1735-1756. [PMID: 34056803 PMCID: PMC8376411 DOI: 10.1002/pro.4133] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 05/23/2021] [Accepted: 05/25/2021] [Indexed: 12/17/2022]
Abstract
Evolutionary selection ensures specificity and efficiency in dynamic metastable macromolecular machines that repair DNA damage without releasing toxic and mutagenic intermediates. Here we examine non‐homologous end joining (NHEJ) as the primary conserved DNA double‐strand break (DSB) repair process in human cells. NHEJ has exemplary key roles in networks determining the development, outcome of cancer treatments by DSB‐inducing agents, generation of antibody and T‐cell receptor diversity, and innate immune response for RNA viruses. We determine mechanistic insights into NHEJ structural biochemistry focusing upon advanced small angle X‐ray scattering (SAXS) results combined with X‐ray crystallography (MX) and cryo‐electron microscopy (cryo‐EM). SAXS coupled to atomic structures enables integrated structural biology for objective quantitative assessment of conformational ensembles and assemblies in solution, intra‐molecular distances, structural similarity, functional disorder, conformational switching, and flexibility. Importantly, NHEJ complexes in solution undergo larger allosteric transitions than seen in their cryo‐EM or MX structures. In the long‐range synaptic complex, X‐ray repair cross‐complementing 4 (XRCC4) plus XRCC4‐like‐factor (XLF) form a flexible bridge and linchpin for DNA ends bound to KU heterodimer (Ku70/80) and DNA‐PKcs (DNA‐dependent protein kinase catalytic subunit). Upon binding two DNA ends, auto‐phosphorylation opens DNA‐PKcs dimer licensing NHEJ via concerted conformational transformations of XLF‐XRCC4, XLF–Ku80, and LigIVBRCT–Ku70 interfaces. Integrated structures reveal multifunctional roles for disordered linkers and modular dynamic interfaces promoting DSB end processing and alignment into the short‐range complex for ligation by LigIV. Integrated findings define dynamic assemblies fundamental to designing separation‐of‐function mutants and allosteric inhibitors targeting conformational transitions in multifunctional complexes.
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Affiliation(s)
- Michal Hammel
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - John A Tainer
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, California, USA.,Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Molecular and Cellular Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
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27
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A synthetically lethal nanomedicine delivering novel inhibitors of polynucleotide kinase 3'-phosphatase (PNKP) for targeted therapy of PTEN-deficient colorectal cancer. J Control Release 2021; 334:335-352. [PMID: 33933518 DOI: 10.1016/j.jconrel.2021.04.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 04/24/2021] [Accepted: 04/27/2021] [Indexed: 11/21/2022]
Abstract
Phosphatase and TENsin homolog deleted on chromosome 10 (PTEN) is a major tumor-suppressor protein that is lost in up to 75% of aggressive colorectal cancers (CRC). The co-depletion of PTEN and a DNA repair protein, polynucleotide kinase 3'-phosphatase (PNKP), has been shown to lead to synthetic lethality in several cancer types including CRC. This finding inspired the development of novel PNKP inhibitors as potential new drugs against PTEN-deficient CRC. Here, we report on the in vitro and in vivo evaluation of a nano-encapsulated potent, but poorly water-soluble lead PNKP inhibitor, A83B4C63, as a new targeted therapeutic for PTEN-deficient CRC. Our data confirmed the binding of A83B4C63, as free or nanoparticle (NP) formulation, to intracellular PNKP using the cellular thermal shift assay (CETSA), in vitro and in vivo. Dose escalating toxicity studies in healthy CD-1 mice, based on measurement of animal weight changes and biochemical blood analysis, revealed the safety of both free and nano-encapsulated A83B4C63, at assessed doses of ≤50 mg/kg. Nano-carriers of A83B4C63 effectively inhibited the growth of HCT116/PTEN-/- xenografts in NIH-III nude mice following intravenous (IV) administration, but not that of wild-type HCT116/PTEN+/+ xenografts. This was in contrast to IV administration of A83B4C63 solubilized with the aid of Cremophor EL: Ethanol (CE), which led to similar tumor growth to that of formulation excipients (NP or CE without drug) or 5% dextrose. This observation was attributed to the higher levels of A83B4C63 delivered to tumor tissue by its NP formulation. Our data provide evidence for the success of NPs of A83B4C63, as novel synthetically lethal nano-therapeutics in the treatment of PTEN-deficient CRC. This research also highlights the potential of successful application of nanomedicine in the drug development process.
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28
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Roychoudhury K, Hegde RS. The Eyes Absent Proteins: Unusual HAD Family Tyrosine Phosphatases. Int J Mol Sci 2021; 22:ijms22083925. [PMID: 33920226 PMCID: PMC8069645 DOI: 10.3390/ijms22083925] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/30/2021] [Accepted: 04/03/2021] [Indexed: 01/21/2023] Open
Abstract
Here, we review the haloacid dehalogenase (HAD) class of protein phosphatases, with a particular emphasis on an unusual group of enzymes, the eyes absent (EYA) family. EYA proteins have the unique distinction of being structurally and mechanistically classified as HAD enzymes, yet, unlike other HAD phosphatases, they are protein tyrosine phosphatases (PTPs). Further, the EYA proteins are unique among the 107 classical PTPs in the human genome because they do not use a Cysteine residue as a nucleophile in the dephosphorylation reaction. We will provide an overview of HAD phosphatase structure-function, describe unique features of the EYA family and their tyrosine phosphatase activity, provide a brief summary of the known substrates and cellular functions of the EYA proteins, and speculate about the evolutionary origins of the EYA family of proteins.
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Ghosh D, Raghavan SC. Nonhomologous end joining: new accessory factors fine tune the machinery. Trends Genet 2021; 37:582-599. [PMID: 33785198 DOI: 10.1016/j.tig.2021.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 03/01/2021] [Accepted: 03/04/2021] [Indexed: 01/08/2023]
Abstract
Nonhomologous DNA end joining (NHEJ) is one of the major DNA double-strand break (DSB) repair pathways in eukaryotes. The well-known critical proteins involved in NHEJ include Ku70/80, DNA-PKcs, Artemis, DNA pol λ/μ, DNA ligase IV-XRCC4, and XLF. Recent studies have added a number of new proteins to the NHEJ repertoire namely paralog of XRCC4 and XLF (PAXX), modulator of retroviral infection (MRI)/ cell cycle regulator of NHEJ (CYREN), transactivation response DNA-binding protein (TARDBP) of 43 kDa (TDP-43), intermediate filament family orphan (IFFO1), ERCC excision repair 6 like 2 (ERCC6L2), and RNase H2. PAXX acts as a stabilizing factor for the main NHEJ components. MRI/CYREN seems to play a dual role stimulating NHEJ in the G1 phase of the cell cycle, while inhibiting the pathway in the S and G2 phases. TDP-43 can recruit the ligase IV-XRCC4 complex to the DSB sites and stimulate ligation in neuronal cells. RNase H2 excises out the ribonucleotides inserted during repair by DNA polymerase μ/TdT. This review provides a brief glimpse into how these new partners were discovered and their contribution to the mechanism and regulation of NHEJ.
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Affiliation(s)
- Dipayan Ghosh
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sathees C Raghavan
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India.
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30
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Targeting RNF8 effectively reverses cisplatin and doxorubicin resistance in endometrial cancer. Biochem Biophys Res Commun 2021; 545:89-97. [PMID: 33548629 DOI: 10.1016/j.bbrc.2021.01.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 01/17/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Endometrial cancer (EC) is one of the most frequent gynecological malignancy worldwide. However, resistance to chemotherapy remains one of the major difficulties in the treatment of EC. Thus, there is an urgent requirement to understand mechanisms of chemoresistance and identify novel regimens for patients with EC. We found that protein and mRNA expression levels of RNF8 were significantly increased in both cisplatin and doxorubicin resistant EC cells. Cell survival assay showed that RNF deficiency significantly enhanced the sensitivity of resistant EC cells to cisplatin and doxorubicin (P < 0.01). In addition, chemoresistant EC cells exhibited increased NHEJ efficiency. Knockout of RNF8 in chemoresistant EC cells significantly reduced NHEJ efficiency and prolonged Ku80 retention on DSB. Moreover, cisplatin resistant AN3CA xenograft showed that RNF8 deficiency overcame cisplatin resistance. Our in vitro and in vivo assays provide evidence for RNF8, which is a NHEJ factor, serving as a promising, novel target in EC chemotherapy.
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31
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Structural insights into the role of DNA-PK as a master regulator in NHEJ. GENOME INSTABILITY & DISEASE 2021; 2:195-210. [PMID: 34723130 PMCID: PMC8549938 DOI: 10.1007/s42764-021-00047-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/06/2021] [Accepted: 07/12/2021] [Indexed: 12/26/2022]
Abstract
DNA-dependent protein kinase catalytic subunit DNA-PKcs/PRKDC is the largest serine/threonine protein kinase of the phosphatidyl inositol 3-kinase-like protein kinase (PIKK) family and is the most highly expressed PIKK in human cells. With its DNA-binding partner Ku70/80, DNA-PKcs is required for regulated and efficient repair of ionizing radiation-induced DNA double-strand breaks via the non-homologous end joining (NHEJ) pathway. Loss of DNA-PKcs or other NHEJ factors leads to radiation sensitivity and unrepaired DNA double-strand breaks (DSBs), as well as defects in V(D)J recombination and immune defects. In this review, we highlight the contributions of the late Dr. Carl W. Anderson to the discovery and early characterization of DNA-PK. We furthermore build upon his foundational work to provide recent insights into the structure of NHEJ synaptic complexes, an evolutionarily conserved and functionally important YRPD motif, and the role of DNA-PKcs and its phosphorylation in NHEJ. The combined results identify DNA-PKcs as a master regulator that is activated by its detection of two double-strand DNA ends for a cascade of phosphorylation events that provide specificity and efficiency in assembling the synaptic complex for NHEJ.
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32
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Bermúdez-Guzmán L, Jimenez-Huezo G, Arguedas A, Leal A. Mutational survivorship bias: The case of PNKP. PLoS One 2020; 15:e0237682. [PMID: 33332469 PMCID: PMC7746193 DOI: 10.1371/journal.pone.0237682] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 11/23/2020] [Indexed: 01/21/2023] Open
Abstract
The molecular function of a protein relies on its structure. Understanding how variants alter structure and function in multidomain proteins is key to elucidate the generation of a pathological phenotype. However, one may fall into the logical bias of assessing protein damage only based on the variants that are visible (survivorship bias), which can lead to partial conclusions. This is the case of PNKP, an important nuclear and mitochondrial DNA repair enzyme with both kinase and phosphatase function. Most variants in PNKP are confined to the kinase domain, leading to a pathological spectrum of three apparently distinct clinical entities. Since proteins and domains may have a different tolerability to variation, we evaluated whether variants in PNKP are under survivorship bias. Here, we provide the evidence that supports a higher tolerance in the kinase domain even when all variants reported are deleterious. Instead, the phosphatase domain is less tolerant due to its lower variant rates, a higher degree of sequence conservation, lower dN/dS ratios, and the presence of more disease-propensity hotspots. Together, our results support previous experimental evidence that demonstrated that the phosphatase domain is functionally more necessary and relevant for DNA repair, especially in the context of the development of the central nervous system. Finally, we propose the term "Wald’s domain" for future studies analyzing the possible survivorship bias in multidomain proteins.
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Affiliation(s)
- Luis Bermúdez-Guzmán
- Section of Genetics and Biotechnology, School of Biology, University de Costa Rica, San Pedro, San José, Costa Rica
| | - Gabriel Jimenez-Huezo
- Section of Genetics and Biotechnology, School of Biology, University de Costa Rica, San Pedro, San José, Costa Rica
| | - Andrés Arguedas
- School of Statistics, University de Costa Rica, San Pedro, San José, Costa Rica
| | - Alejandro Leal
- Section of Genetics and Biotechnology, School of Biology, University de Costa Rica, San Pedro, San José, Costa Rica
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33
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Dong W, Li L, Teng X, Yang X, Si S, Chai J. End Processing Factor APLF Promotes NHEJ Efficiency and Contributes to TMZ- and Ionizing Radiation-Resistance in Glioblastoma Cells. Onco Targets Ther 2020; 13:10593-10605. [PMID: 33116637 PMCID: PMC7584509 DOI: 10.2147/ott.s254292] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/02/2020] [Indexed: 11/23/2022] Open
Abstract
Purpose Glioblastoma (GBM) is the most commonly diagnosed primary brain tumor in adults. Despite a variety of advances in the understanding of GBM cancer biology during recent decades, very few of them were applied into treatment, and the survival rate of GBM patients has not been improved majorly due to the low chemosensitivity to temozolomide (TMZ) or low radiosensitivity. Therefore, it is urgent to elucidate mechanisms of TMZ- and IR-resistance and develop novel therapeutic strategies to improve GBM treatment. Methods TMZ- and IR-resistant cell lines were acquired by continuous exposing parental GBM cells to TMZ or IR for 3 months. Cell viability was determined by using Sulforhodamine B (SRB) assay. Protein and mRNA expression were examined by Western blotting assay and quantitative polymerase chain reaction (qPCR) assay, respectively. Homologous recombination (HR) and nonhomologous end joining (NHEJ) efficiency were measured by HR and NHEJ reporter assay. Cell apoptosis was determined by Caspase3/7 activity. Autophagy was analyzed using CYTO-ID® Autophagy detection kit. Tumor growth was examined by U87 xenograft mice model. Results DNA repair efficiency of non-homologous end joining (NHEJ) pathway is significantly increased in TMZ- and IR-resistant GBM cells. Importantly, APLF, which is one of the DNA end processing factors in NHEJ, is upregulated in TMZ- and IR-resistant GBM cells and patients. APLF deficiency significantly decreases NHEJ efficiency and improves cell sensitivity to TMZ and IR both in vitro and in vivo. Conclusion Our study provides evidence for APLF serving as a promising, novel target in GBM chemo- and radio-therapy.
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Affiliation(s)
- Wei Dong
- Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academic Sciences, Jinan, Shandong, People's Republic of China
| | - Lanlan Li
- Binzhou Medical University Hospital, Binzhou, Shandong, People's Republic of China
| | - Xuepeng Teng
- Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academic Sciences, Jinan, Shandong, People's Republic of China
| | - Xinhua Yang
- Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academic Sciences, Jinan, Shandong, People's Republic of China
| | - Shujing Si
- Department of Oncology, Gaoqing People's Hospital, Zibo, Shandong, People's Republic of China
| | - Jie Chai
- Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academic Sciences, Jinan, Shandong, People's Republic of China
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34
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Lin M, Wan H, Zhang J, Wang Q, Hu X, Xia F. Electrochemical DNA Sensors Based on MoS 2-AuNPs for Polynucleotide Kinase Activity and Inhibition Assay. ACS APPLIED MATERIALS & INTERFACES 2020; 12:45814-45821. [PMID: 32877162 DOI: 10.1021/acsami.0c13385] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The determination of T4 polynucleotide kinase (PNK) activity and the screening of PNK inhibitors are critical to disease diagnosis and drug discovery. Numerous electrochemical strategies have been developed for the sensitive measurement of PNK activity and inhibition. However, they often suffer from additional labels and multiple steps of the detection process for the electrochemical readout. Herein, we have demonstrated an electrochemical DNA (E-DNA) sensor for the one-step detection of PNK with "signal-on" readout with no need for additional labels. In our design, the highly switchable double-stranded DNA (dsDNA) probes are immobilized on the gold nanoparticle-decorated molybdenum disulfide nanomaterial (MoS2-AuNPs), which possesses large surface area and high conductivity for elevating the signal gain in the PNK detection. This signal-on E-DNA sensor integrated with MoS2-AuNPs exhibits a much higher sensitivity than that without MoS2-AuNPs, showing a detection limit of 2.18 × 10-4 U/mL. Furthermore, this assay shows high selectivity, with the ability to discriminate PNK from other enzymes and proteins, and can be utilized to screen inhibitors. The proposed sensor is easy to operate with one-step readout and robust for PNK detection in the biological matrix and shows great potential for point-of-care in clinical diagnostics and drug screening.
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Affiliation(s)
- Meihua Lin
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Hao Wan
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Jian Zhang
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Quan Wang
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Xinyu Hu
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
| | - Fan Xia
- Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China
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35
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Mao J, Chen X, Xu H, Xu X. DNAzyme-driven DNA walker biosensor for amplified electrochemical detection of T4 polynucleotide kinase activity and inhibition. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114470] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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36
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Tsukada K, Matsumoto Y, Shimada M. Linker region is required for efficient nuclear localization of polynucleotide kinase phosphatase. PLoS One 2020; 15:e0239404. [PMID: 32970693 PMCID: PMC7514006 DOI: 10.1371/journal.pone.0239404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 09/05/2020] [Indexed: 01/10/2023] Open
Abstract
Polynucleotide kinase phosphatase (PNKP) is a DNA repair factor with dual enzymatic functions, i.e., phosphorylation of 5’-end and dephosphorylation of 3’-end, which are prerequisites for DNA ligation and, thus, is involved in multiple DNA repair pathways, i.e., base excision repair, single-strand break repair and double-strand break repair through non-homologous end joining. Mutations in PNKP gene causes inherited diseases, such as microcephaly and seizure (MCSZ) by neural developmental failure and ataxia with oculomotor apraxia 4 (AOA4) and Charcot-Marie-Tooth disease 2B2 (CMT2B2) by neurodegeneration. PNKP consists of the Forkhead-associated (FHA) domain, linker region, phosphatase domain and kinase domain. Although the functional importance of PNKP interaction with XRCC1 and XRCC4 through the FHA domain and that of phosphatase and kinase enzyme activities have been well established, little is known about the function of linker region. In this study, we identified a functional putative nuclear localization signal (NLS) of PNKP located in the linker region, and showed that lysine 138 (K138), arginine 139 (R139) and arginine 141 (R141) residues therein are critically important for nuclear localization. Furthermore, double mutant of K138A and R35A, the latter of which mutates arginine 35, central amino acid of FHA domain, showed additive effect on nuclear localization, indicating that the FHA domain as well as the NLS is important for PNKP nuclear localization. Thus, this study revealed two distinct mechanisms regulating nuclear localization and subnuclear distribution of PNKP. These findings would contribute to deeper understanding of a variety of DNA repair pathway, i.e., base excision repair, single-strand break repair and double-strand break repair.
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Affiliation(s)
- Kaima Tsukada
- Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, Japan
| | - Yoshihisa Matsumoto
- Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, Japan
| | - Mikio Shimada
- Laboratory for Advanced Nuclear Energy, Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, Japan
- * E-mail:
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37
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Kalasova I, Hailstone R, Bublitz J, Bogantes J, Hofmann W, Leal A, Hanzlikova H, Caldecott KW. Pathological mutations in PNKP trigger defects in DNA single-strand break repair but not DNA double-strand break repair. Nucleic Acids Res 2020; 48:6672-6684. [PMID: 32504494 PMCID: PMC7337934 DOI: 10.1093/nar/gkaa489] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/30/2020] [Accepted: 06/04/2020] [Indexed: 12/20/2022] Open
Abstract
Hereditary mutations in polynucleotide kinase-phosphatase (PNKP) result in a spectrum of neurological pathologies ranging from neurodevelopmental dysfunction in microcephaly with early onset seizures (MCSZ) to neurodegeneration in ataxia oculomotor apraxia-4 (AOA4) and Charcot-Marie-Tooth disease (CMT2B2). Consistent with this, PNKP is implicated in the repair of both DNA single-strand breaks (SSBs) and DNA double-strand breaks (DSBs); lesions that can trigger neurodegeneration and neurodevelopmental dysfunction, respectively. Surprisingly, however, we did not detect a significant defect in DSB repair (DSBR) in primary fibroblasts from PNKP patients spanning the spectrum of PNKP-mutated pathologies. In contrast, the rate of SSB repair (SSBR) is markedly reduced. Moreover, we show that the restoration of SSBR in patient fibroblasts collectively requires both the DNA kinase and DNA phosphatase activities of PNKP, and the fork-head associated (FHA) domain that interacts with the SSBR protein, XRCC1. Notably, however, the two enzymatic activities of PNKP appear to affect different aspects of disease pathology, with reduced DNA phosphatase activity correlating with neurodevelopmental dysfunction and reduced DNA kinase activity correlating with neurodegeneration. In summary, these data implicate reduced rates of SSBR, not DSBR, as the source of both neurodevelopmental and neurodegenerative pathology in PNKP-mutated disease, and the extent and nature of this reduction as the primary determinant of disease severity.
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Affiliation(s)
- Ilona Kalasova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Richard Hailstone
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Janin Bublitz
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Jovel Bogantes
- Servicio de Cirugía Reconstructiva, Hospital Rafael Ángel Calderón Guardia, Caja Costarricense de Seguro Social, San José, Costa Rica
| | - Winfried Hofmann
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Alejandro Leal
- Section of Genetics and Biotechnology, School of Biology, University of Costa Rica, San José, Costa Rica
| | - Hana Hanzlikova
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
| | - Keith W Caldecott
- Department of Genome Dynamics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton BN1 9RQ, UK
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38
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Aleksandrov R, Hristova R, Stoynov S, Gospodinov A. The Chromatin Response to Double-Strand DNA Breaks and Their Repair. Cells 2020; 9:cells9081853. [PMID: 32784607 PMCID: PMC7464352 DOI: 10.3390/cells9081853] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023] Open
Abstract
Cellular DNA is constantly being damaged by numerous internal and external mutagenic factors. Probably the most severe type of insults DNA could suffer are the double-strand DNA breaks (DSBs). They sever both DNA strands and compromise genomic stability, causing deleterious chromosomal aberrations that are implicated in numerous maladies, including cancer. Not surprisingly, cells have evolved several DSB repair pathways encompassing hundreds of different DNA repair proteins to cope with this challenge. In eukaryotic cells, DSB repair is fulfilled in the immensely complex environment of the chromatin. The chromatin is not just a passive background that accommodates the multitude of DNA repair proteins, but it is a highly dynamic and active participant in the repair process. Chromatin alterations, such as changing patterns of histone modifications shaped by numerous histone-modifying enzymes and chromatin remodeling, are pivotal for proficient DSB repair. Dynamic chromatin changes ensure accessibility to the damaged region, recruit DNA repair proteins, and regulate their association and activity, contributing to DSB repair pathway choice and coordination. Given the paramount importance of DSB repair in tumorigenesis and cancer progression, DSB repair has turned into an attractive target for the development of novel anticancer therapies, some of which have already entered the clinic.
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Ubiquitylation-Mediated Fine-Tuning of DNA Double-Strand Break Repair. Cancers (Basel) 2020; 12:cancers12061617. [PMID: 32570875 PMCID: PMC7352447 DOI: 10.3390/cancers12061617] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/15/2020] [Accepted: 06/17/2020] [Indexed: 01/04/2023] Open
Abstract
The proper function of DNA repair is indispensable for eukaryotic cells since accumulation of DNA damages leads to genome instability and is a major cause of oncogenesis. Ubiquitylation and deubiquitylation play a pivotal role in the precise regulation of DNA repair pathways by coordinating the recruitment and removal of repair proteins at the damaged site. Here, we summarize the most important post-translational modifications (PTMs) involved in DNA double-strand break repair. Although we highlight the most relevant PTMs, we focus principally on ubiquitylation-related processes since these are the most robust regulatory pathways among those of DNA repair.
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40
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Marcilla Vázquez C, Carrascosa Romero MDC, Martínez Gutiérrez A, Baquero Cano M, Alfaro Ponce B, Dabad Moreno MJ. A Novel c.968C > T homozygous Mutation in the Polynucleotide Kinase 3' - Phosphatase Gene Related to the Syndrome of Microcephaly, Seizures, and Developmental Delay. J Pediatr Genet 2020; 10:164-172. [PMID: 34040816 DOI: 10.1055/s-0040-1710540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 04/12/2020] [Indexed: 10/24/2022]
Abstract
Microcephaly is defined by a head circumference that is at least two standard deviations below the mean for age and sex of the general population in a specific race. Primary microcephaly may occur as an isolated inborn error, which may damage to the central nervous system or as part of the congenital abnormalities associated with genetic syndrome, affecting multiple organ systems. One of the syndromic forms consists of microcephaly, seizures, and developmental delay caused by biallelic mutations in the gene that encode polynucleotide kinase 3' - phosphatase protein (PNKP). In this article, we reported a newborn male who presented with microcephaly, severe developmental delay, and early-onset refractories seizures, caused by a novel homozygous mutation of the PNKP gene.
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41
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Pillon MC, Stanley RE. Nonradioactive Assay to Measure Polynucleotide Phosphorylation of Small Nucleotide Substrates. J Vis Exp 2020. [PMID: 32449708 DOI: 10.3791/61258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Polynucleotide kinases (PNKs) are enzymes that catalyze the phosphorylation of the 5' hydroxyl end of DNA and RNA oligonucleotides. The activity of PNKs can be quantified using direct or indirect approaches. Presented here is a direct, in vitro approach to measure PNK activity that relies on a fluorescently-labeled oligonucleotide substrate and polyacrylamide gel electrophoresis. This approach provides resolution of the phosphorylated products while avoiding the use of radiolabeled substrates. The protocol details how to set up the phosphorylation reaction, prepare and run large polyacrylamide gels, and quantify the reaction products. The most technically challenging part of this assay is pouring and running the large polyacrylamide gels; thus, important details to overcome common difficulties are provided. This protocol was optimized for Grc3, a PNK that assembles into an obligate pre-ribosomal RNA processing complex with its binding partner, the Las1 nuclease. However, this protocol can be adapted to measure the activity of other PNK enzymes. Moreover, this assay can also be modified to determine the effects of different components of the reaction, such as the nucleoside triphosphate, metal ions, and oligonucleotides.
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Affiliation(s)
- Monica C Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health
| | - Robin E Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, Department of Health and Human Services, National Institutes of Health;
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42
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Gándola YB, Fontana C, Bojorge MA, Luschnat TT, Moretton MA, Chiapetta DA, Verstraeten SV, González L. Concentration-dependent effects of sodium cholate and deoxycholate bile salts on breast cancer cells proliferation and survival. Mol Biol Rep 2020; 47:3521-3539. [PMID: 32297292 DOI: 10.1007/s11033-020-05442-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/06/2020] [Indexed: 11/24/2022]
Abstract
Bile acids (BAs) are bioactive molecules that have potential therapeutic interest and their derived salts are used in several pharmaceutical systems. BAs have been associated with tumorigenesis of several tissues including the mammary tissue. Therefore, it is crucial to characterize their effects on cancer cells. The objective of this work was to analyse the molecular and cellular effects of the bile salts sodium cholate and sodium deoxycholate on epithelial breast cancer cell lines. Bile salts (BSs) effects over breast cancer cells viability and proliferation were assessed by MTS and BrdU assays, respectively. Activation of cell signaling mediators was determined by immunobloting. Microscopy was used to analyze cell migration, and cellular and nuclear morphology. Interference of membrane fluidity was studied by generalized polarization and fluorescence anisotropy. BSs preparations were characterized by transmission electron microscopy and dynamic light scattering. Sodium cholate and sodium deoxycholate had dual effects on cell viability, increasing it at the lower concentrations assessed and decreasing it at the highest ones. The increase of cell viability was associated with the promotion of AKT phosphorylation and cyclin D1 expression. High concentrations of bile salts induced apoptosis as well as sustained activation of p38 and AKT. In addition, they affected cell membrane fluidity but not significant effects on cell migration were observed. In conclusion, bile salts have concentration-dependent effects on breast cancer cells, promoting cell proliferation at physiological levels and being cytotoxic at supraphysiological ones. Their effects were associated with the activation of kinases involved in cell signalling.
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Affiliation(s)
- Yamila B Gándola
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Camila Fontana
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Mariana A Bojorge
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Tania T Luschnat
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Marcela A Moretton
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Facultad de Farmacia y Bioquímica, Departamento de Tecnología Farmacéutica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Diego A Chiapetta
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Facultad de Farmacia y Bioquímica, Departamento de Tecnología Farmacéutica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Sandra V Verstraeten
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina
| | - Lorena González
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Instituto de Química y Fisicoquímica Biológicas (IQUIFIB), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina. .,Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956 (1113), Buenos Aires, Argentina.
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43
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Saito M, Sato A, Nagata S, Tamaki S, Tomita M, Suzuki H, Kanai A. Large-Scale Molecular Evolutionary Analysis Uncovers a Variety of Polynucleotide Kinase Clp1 Family Proteins in the Three Domains of Life. Genome Biol Evol 2020; 11:2713-2726. [PMID: 31513263 PMCID: PMC6777427 DOI: 10.1093/gbe/evz195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2019] [Indexed: 01/13/2023] Open
Abstract
Clp1, a polyribonucleotide 5′-hydroxyl kinase in eukaryotes, is involved in pretRNA splicing and mRNA 3′-end formation. Enzymes similar in amino acid sequence to Clp1, Nol9, and Grc3, are present in some eukaryotes and are involved in prerRNA processing. However, our knowledge of how these Clp1 family proteins evolved and diversified is limited. We conducted a large-scale molecular evolutionary analysis of the Clp1 family proteins in all living organisms for which protein sequences are available in public databases. The phylogenetic distribution and frequencies of the Clp1 family proteins were investigated in complete genomes of Bacteria, Archaea and Eukarya. In total, 3,557 Clp1 family proteins were detected in the three domains of life, Bacteria, Archaea, and Eukarya. Many were from Archaea and Eukarya, but a few were found in restricted, phylogenetically diverse bacterial species. The domain structures of the Clp1 family proteins also differed among the three domains of life. Although the proteins were, on average, 555 amino acids long (range, 196–2,728), 122 large proteins with >1,000 amino acids were detected in eukaryotes. These novel proteins contain the conserved Clp1 polynucleotide kinase domain and various other functional domains. Of these proteins, >80% were from Fungi or Protostomia. The polyribonucleotide kinase activity of Thermus scotoductus Clp1 (Ts-Clp1) was characterized experimentally. Ts-Clp1 preferentially phosphorylates single-stranded RNA oligonucleotides (Km value for ATP, 2.5 µM), or single-stranded DNA at higher enzyme concentrations. We propose a comprehensive assessment of the diversification of the Clp1 family proteins and the molecular evolution of their functional domains.
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Affiliation(s)
- Motofumi Saito
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.,Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Japan
| | - Asako Sato
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan
| | - Shohei Nagata
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.,Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Japan
| | - Satoshi Tamaki
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan
| | - Masaru Tomita
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.,Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Japan.,Faculty of Environment and Information Studies, Keio University, Fujisawa, Japan
| | - Haruo Suzuki
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.,Faculty of Environment and Information Studies, Keio University, Fujisawa, Japan
| | - Akio Kanai
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Japan.,Systems Biology Program, Graduate School of Media and Governance, Keio University, Fujisawa, Japan.,Faculty of Environment and Information Studies, Keio University, Fujisawa, Japan
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A nanoplatform based on metal-organic frameworks and coupled exonuclease reaction for the fluorimetric determination of T4 polynucleotide kinase activity and inhibition. Mikrochim Acta 2020; 187:243. [PMID: 32206934 DOI: 10.1007/s00604-020-4194-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/25/2020] [Indexed: 10/24/2022]
Abstract
A nanoplatform based on metal-organic frameworks (MOFs) and lambda exonuclease (λ exo) for the fluorimetric determination of T4 polynucleotide kinase (T4 PNK) activity and inhibition is described. Fe-MIL-88 was selected as the nanomaterial because of its significant preferential binding ability to single-stranded DNA (ssDNA) over double-stranded DNA (dsDNA) and its quenching property. The synthesized Fe-MIL-88 was characterized by transmission electron microscope, scanning electron microscope, and X-ray photoelectron spectroscopy. In the presence of T4 PNK, FAM-labeled dsDNA (FAM-dsDNA) is phosphorylated on its 5'-terminal. λ exo then recognizes and cleaves the phosphorylated strand yielding FAM-labeled ssDNA (FAM-ssDNA). The fluorescence of the produced FAM-ssDNA is quenched due to Fe-MIL-88's absorbing on FAM-ssDNA. On the contrary, in the absence of T4 PNK, the phosphorylation and cleavage processes cannot take place. Therefore, the fluorescence of FAM-dsDNA still remains. The fluorescence intensity is detected at the maximum emission wavelength of 524 nm using the maximum excitation wavelength of 488 nm. The assay of T4 PNK based on the fluorescence quenching of FAM-ssDNA achieves a linear relationship in the range 0.01-5.0 U mL-1 with a detection limit of 0.0089 U mL-1 in buffer. The assay exhibits excellent performance for T4 PNK activity determination in a complex biological matrix. The results also reveal the ability of the assay for T4 PNK inhibitor screening. Graphical abstract Schematic presentation of a nanoplatform based on Fe-MIL-88 and coupled exonuclease reaction for the fluorimetric determination of T4 polynucleotide kinase activity. FAM-ssDNA, FAM-labeled single-stranded DNA; cDNA, complementary DNA; λ exo, lambda exonuclease;T4 PNK, T4 polynucleotide kinase.
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45
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Campopiano R, Ferese R, Buttari F, Femiano C, Centonze D, Fornai F, Biagioni F, Chiaravalloti MA, Magnani M, Giardina E, Ruzzo A, Gambardella S. A Novel Homozygous Variant in the Fork-Head-Associated Domain of Polynucleotide Kinase Phosphatase in a Patient Affected by Late-Onset Ataxia With Oculomotor Apraxia Type 4. Front Neurol 2020; 10:1331. [PMID: 32010037 PMCID: PMC6974581 DOI: 10.3389/fneur.2019.01331] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 12/02/2019] [Indexed: 11/13/2022] Open
Abstract
Ataxia with oculomotor apraxia (AOA) is a clinical syndrome featuring a group of genetic diseases including at least four separate autosomal-recessive cerebellar ataxias. All these disorders are due to altered genes involved in DNA repair. AOA type 4 (AOA4) is caused by mutations in DNA repair factor polynucleotide kinase phosphatase (PNKP), which encodes for a DNA processing enzyme also involved in other syndromes featured by microcephaly or neurodegeneration. To date, only a few AOA4 patients have been reported worldwide. All these patients are homozygous or compound heterozygous carriers for mutations in the kinase domain of PNKP. In this report, we describe a 56 years old patient affected by AOA4 characterized by ataxia, polyneuropathy, oculomotor apraxia, and cognitive impairment with the absence of dystonia. The disease is characterized by a very late onset (50 years) when compared with other AOA4 patients described so far (median age of onset at 4 years). In this proband, Clinical Exome Analysis through Next Generation Sequencing (NGS) consisting of 4,800 genes, identified the PNKP homozygous mutation p.Gln50Glu. This variant, classified as a likely pathogenic variant according to American College of Medical Genetics (ACMG) guidelines, does not involve the kinase domain but falls in the fork-head-associated (FHA) domain. So far, mutations in such a domain were reported to associate only with a pure seizure syndrome without the classic AOA4 features. Therefore, this is the first report of patients carrying a mutation of the FHA domain within the PNKP gene which expresses the clinical phenotype known as the AOA4 syndrome and the lack of any seizure activity. Further studies are required to investigate specifically the significance of various mutations within the FHA domain, and it would be worth to correlate these variants with the age of onset of the AOA4 syndrome.
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Affiliation(s)
| | | | | | | | - Diego Centonze
- IRCCS Neuromed, Pozzilli, Italy.,Dipartimento di Medicina dei Sistemi, Università di Roma Tor Vergata, Rome, Italy
| | - Francesco Fornai
- IRCCS Neuromed, Pozzilli, Italy.,Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | | | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Emiliano Giardina
- Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Rome, Italy.,Molecular Genetics Laboratory UILDM, Santa Lucia Foundation, Rome, Italy
| | - Anna Ruzzo
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
| | - Stefano Gambardella
- IRCCS Neuromed, Pozzilli, Italy.,Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
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46
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Jin T, Zhang J, Zhao Y, Huang X, Tan C, Sun S, Tan Y. Magnetic bead-gold nanoparticle hybrids probe based on optically countable gold nanoparticles with dark-field microscope for T4 polynucleotide kinase activity assay. Biosens Bioelectron 2020; 150:111936. [DOI: 10.1016/j.bios.2019.111936] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 11/12/2019] [Accepted: 11/27/2019] [Indexed: 12/12/2022]
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47
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Du YC, Wang SY, Li XY, Wang YX, Tang AN, Kong DM. Terminal deoxynucleotidyl transferase-activated nicking enzyme amplification reaction for specific and sensitive detection of DNA methyltransferase and polynucleotide kinase. Biosens Bioelectron 2019; 145:111700. [DOI: 10.1016/j.bios.2019.111700] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 08/28/2019] [Accepted: 09/11/2019] [Indexed: 12/19/2022]
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48
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Li C, Wong JTY. DNA Damage Response Pathways in Dinoflagellates. Microorganisms 2019; 7:E191. [PMID: 31284474 PMCID: PMC6680887 DOI: 10.3390/microorganisms7070191] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/29/2019] [Accepted: 07/01/2019] [Indexed: 12/17/2022] Open
Abstract
Dinoflagellates are a general group of phytoplankton, ubiquitous in aquatic environments. Most dinoflagellates are non-obligate autotrophs, subjected to potential physical and chemical DNA-damaging agents, including UV irradiation, in the euphotic zone. Delay of cell cycles by irradiation, as part of DNA damage responses (DDRs), could potentially lead to growth inhibition, contributing to major errors in the estimation of primary productivity and interpretations of photo-inhibition. Their liquid crystalline chromosomes (LCCs) have large amount of abnormal bases, restricted placement of coding sequences at the chromosomes periphery, and tandem repeat-encoded genes. These chromosome characteristics, their large genome sizes, as well as the lack of architectural nucleosomes, likely contribute to possible differential responses to DNA damage agents. In this study, we sought potential dinoflagellate orthologues of eukaryotic DNA damage repair pathways, and the linking pathway with cell-cycle control in three dinoflagellate species. It appeared that major orthologues in photoreactivation, base excision repair, nucleotide excision repair, mismatch repair, double-strand break repair and homologous recombination repair are well represented in dinoflagellate genomes. Future studies should address possible differential DNA damage responses of dinoflagellates over other planktonic groups, especially in relation to possible shift of life-cycle transitions in responses to UV irradiation. This may have a potential role in the persistence of dinoflagellate red tides with the advent of climatic change.
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Affiliation(s)
- Chongping Li
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China.
- Division of Life Science, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China.
| | - Joseph Tin Yum Wong
- Division of Life Science, The Hong Kong University of Science and Technology, Clearwater Bay, Kowloon, Hong Kong, China.
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49
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Kopa P, Macieja A, Galita G, Witczak ZJ, Poplawski T. DNA Double Strand Breaks Repair Inhibitors: Relevance as Potential New Anticancer Therapeutics. Curr Med Chem 2019; 26:1483-1493. [PMID: 29446719 DOI: 10.2174/0929867325666180214113154] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/19/2022]
Abstract
DNA double-strand breaks are considered one of the most lethal forms of DNA damage. Many effective anticancer therapeutic approaches used chemical and physical methods to generate DNA double-strand breaks in the cancer cells. They include: IR and drugs which mimetic its action, topoisomerase poisons, some alkylating agents or drugs which affected DNA replication process. On the other hand, cancer cells are mostly characterized by highly effective systems of DNA damage repair. There are two main DNA repair pathways used to fix double-strand breaks: NHEJ and HRR. Their activity leads to a decreased effect of chemotherapy. Targeting directly or indirectly the DNA double-strand breaks response by inhibitors seems to be an exciting option for anticancer therapy and is a part of novel trends that arise after the clinical success of PARP inhibitors. These trends will provide great opportunities for the development of DNA repair inhibitors as new potential anticancer drugs. The main objective of this article is to address these new promising advances.
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Affiliation(s)
- Paulina Kopa
- Department of Immunopathology, Faculty of Biomedical Sciences and Postgraduate Training, Medical University of Lodz, Lodz 90-752, Poland
| | - Anna Macieja
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz 90-236, Poland
| | - Grzegorz Galita
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz 90-236, Poland
| | - Zbigniew J Witczak
- Department of Pharmaceutical Sciences, Nesbitt School of Pharmacy, Wilkes University, Wilkes-Barre, PA 18766, United States
| | - Tomasz Poplawski
- Department of Molecular Genetics, Faculty of Biology and Environmental Protection, University of Lodz, Lodz 90-236, Poland
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50
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Bermúdez-Guzmán L, Leal A. DNA repair deficiency in neuropathogenesis: when all roads lead to mitochondria. Transl Neurodegener 2019; 8:14. [PMID: 31110700 PMCID: PMC6511134 DOI: 10.1186/s40035-019-0156-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/24/2019] [Indexed: 12/18/2022] Open
Abstract
Mutations in DNA repair enzymes can cause two neurological clinical manifestations: a developmental impairment and a degenerative disease. Polynucleotide kinase 3'-phosphatase (PNKP) is an enzyme that is actively involved in DNA repair in both single and double strand break repair systems. Mutations in this protein or others in the same pathway are responsible for a complex group of diseases with a broad clinical spectrum. Besides, mitochondrial dysfunction also has been consolidated as a hallmark of brain degeneration. Here we provide evidence that supports a shared role between mitochondrial dysfunction and DNA repair defects in the pathogenesis of the nervous system. As models, we analyze PNKP-related disorders, focusing on Charcot-Marie-Tooth disease and ataxia. A better understanding of the molecular dynamics of this relationship could provide improved diagnosis and treatment for neurological diseases.
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Affiliation(s)
- Luis Bermúdez-Guzmán
- Section of Genetics and Biotechnology, School of Biology, Universidad de Costa Rica, San José, 11501 Costa Rica
| | - Alejandro Leal
- Section of Genetics and Biotechnology, School of Biology, Universidad de Costa Rica, San José, 11501 Costa Rica
- Neuroscience Research Center, Universidad de Costa Rica, San José, Costa Rica
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