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Menck CFM, Galhardo RS, Quinet A. The accurate bypass of pyrimidine dimers by DNA polymerase eta contributes to ultraviolet-induced mutagenesis. Mutat Res 2023; 828:111840. [PMID: 37984186 DOI: 10.1016/j.mrfmmm.2023.111840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/23/2023] [Accepted: 11/02/2023] [Indexed: 11/22/2023]
Abstract
Human xeroderma pigmentosum variant (XP-V) patients are mutated in the POLH gene, responsible for encoding the translesion synthesis (TLS) DNA polymerase eta (Pol eta). These patients suffer from a high frequency of skin tumors. Despite several decades of research, studies on Pol eta still offer an intriguing paradox: How does this error-prone polymerase suppress mutations? This review examines recent evidence suggesting that cyclobutane pyrimidine dimers (CPDs) are instructional for Pol eta. Consequently, it can accurately replicate these lesions, and the mutagenic effects induced by UV radiation stem from the deamination of C-containing CPDs. In this model, the deamination of C (forming a U) within CPDs leads to the correct insertion of an A opposite to the deaminated C (or U)-containing dimers. This intricate process results in C>T transitions, which represent the most prevalent mutations detected in skin cancers. Finally, the delayed replication in XP-V cells amplifies the process of C-deamination in CPDs and increases the burden of C>T mutations prevalent in XP-V tumors through the activity of backup TLS polymerases.
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Affiliation(s)
- C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil.
| | - R S Galhardo
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
| | - A Quinet
- Université Paris Cité, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, F-92265 Fontenay-aux-Roses, France; Université Paris-Saclay, Inserm, CEA, Stabilité Génétique Cellules Souches et Radiations, LRS/iRCM/IBFJ, F-92265 Fontenay-aux-Roses, France
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2
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Florentino PTV, Vitorino FNL, Mendes D, da Cunha JPC, Menck CFM. Trypanosoma cruzi infection changes the chromatin proteome profile of infected human cells. J Proteomics 2023; 272:104773. [PMID: 36414228 DOI: 10.1016/j.jprot.2022.104773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 10/12/2022] [Accepted: 11/01/2022] [Indexed: 11/21/2022]
Abstract
Chagas disease is endemic in 22 Latin American countries, with approximately 8 million individuals infected worldwide and 10,000 deaths yearly. Trypanosoma cruzi presents an intracellular life cycle in mammalian hosts to sustain infection. Parasite infection activates host cell responses, promoting an unbalance in reactive oxygen species (ROS) in the intracellular environment inducing genomic DNA lesions in the host cell during infection. To further understand changes in host cell chromatin induced by parasite infection, we investigated alterations in chromatin caused by infection by performing quantitative proteomic analysis. DNA Damage Repair proteins, such as Poly-ADP-ribose Polymerase 1 (PARP-1) and X-Ray Repair Cross Complementing 6 (XRRC6), were recruited to the chromatin during infection. Also, changes in chromatin remodeling enzymes suggest that parasite infection may shape the epigenome of the host cells. Interestingly, the abundance of oxidative phosphorylation mitochondrial and vesicle-mediated transport proteins increased in the host chromatin at the final stages of infection. In addition, Apoptosis-inducing Factor (AIF) is translocated to the host cell nucleus upon infection, suggesting that cells enter parthanatos type of death. Altogether, this study reveals how parasites interfere with the host cells' responses at the chromatin level leading to significant crosstalk that support and disseminate infection. SIGNIFICANCE: The present study provides novel insights into the effects of Trypanosoma cruzi on the chromatin from the host cell. This manuscript investigated proteomic alterations in chromatin caused by parasite infection at early and late infection phases by performing a quantitative proteomic analysis. In this study, we revealed that parasites interfere with DNA metabolism in the early and late stages of infection. We identified that proteins related to DNA damage repair, oxidative phosphorylation, and vesicle-mediated transport have increased abundance at the host chromatin. Additionally, we have observed that Apoptosis-inducing Factor is translocated to the host cell nucleus upon infection, suggesting that the parasites could lead the cells to enter Parthanatos as a form of programmed cell death. The findings improve our understanding on how the parasites modulate the host cell chromatin to disseminate infection. In this study, we suggest a mechanistic parasite action towards host nucleus that could be used to indicate targets for future treatments.
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Affiliation(s)
- P T V Florentino
- Dept. of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - F N L Vitorino
- Laboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil.
| | - D Mendes
- Dept. of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - J P C da Cunha
- Laboratory of Cell Cycle, Butantan Institute, São Paulo, Brazil; Center of Toxins, Immune Response and Cell Signaling (CeTICS), Butantan Institute, São Paulo, Brazil
| | - C F M Menck
- Dept. of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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3
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Ramos da Silva J, Ramos Moreno AC, Silva Sales N, de Oliveira Silva M, Aps LRMM, Porchia BFMM, Bitencourt Rodrigues K, Cestari Moreno N, Venceslau-Carvalho AA, Menck CFM, de Oliveira Diniz M, de Souza Ferreira LC. A therapeutic DNA vaccine and gemcitabine act synergistically to eradicate HPV-associated tumors in a preclinical model. Oncoimmunology 2021; 10:1949896. [PMID: 34367730 PMCID: PMC8312617 DOI: 10.1080/2162402x.2021.1949896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Although active immunotherapies are effective strategies to induce activation of CD8+ T cells, advanced stage tumors require further improvements for efficient control. Concerning the burden of cancer-related to Human papillomavirus (HPV), particularly the high incidence and mortality of cervical cancer, our group developed an approach based on a DNA vaccine targeting the HPV-16 E7 oncoprotein (pgDE7h). This immunotherapy is capable of inducing an antitumour CD8+ T cell response but show only partial control of tumors in more advanced growth stages. Here, we combined a chemotherapeutic agent (gemcitabine- Gem) with pgDE7h to overcome immunosuppression and improve antitumour responses in a preclinical mouse tumor model. Our results demonstrated that administration of Gem had synergistic antitumor effects when combined with pgDE7h leading to eradication of both early-stages and established tumors. Overall, the antiproliferative effects of Gem observed in vitro and in vivo provided an optimal window for immunotherapy. In addition, the enhanced antitumour responses induced by the combined therapeutic regimen included enhanced frequencies of antigen-presenting cells (APCs), E7-specific IFN-γ-producing CD8+ T cells, and cytotoxic CD8+ T cells and, concomitantly, less pronounced accumulation of immunosuppressive myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs). These findings demonstrated that the combination of Gem and an active immunotherapy strategy show increased effectiveness, leading to a reduced need for multiple drug doses and, therefore, decreased deleterious side effects avoiding resistance and tumor relapses. Altogether, our results provide evidence for a new and feasible chemoimmunotherapeutic strategy that supports future clinical translation.
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Affiliation(s)
- Jamile Ramos da Silva
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Ana Carolina Ramos Moreno
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Natiely Silva Sales
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Mariângela de Oliveira Silva
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Luana R M M Aps
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Bruna F M M Porchia
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil.,Laboratory of Tumor Immunology, Department of Immunology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Karine Bitencourt Rodrigues
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Natália Cestari Moreno
- DNA Repair Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil.,Mitochondrial Genetics Lab. Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Carlos Frederico M Menck
- DNA Repair Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
| | - Mariana de Oliveira Diniz
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil.,Division of Infection and Immunity, University College London, 5 University St, Bloomsbury, London, UK
| | - Luís Carlos de Souza Ferreira
- Vaccine Development Laboratory, Department of Microbiology, Biomedical Sciences Institute, University of São Paulo, São Paulo, Brazil
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4
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Santiago KM, Castro LP, Neto JPD, de Nóbrega AF, Pinto CAL, Ashton-Prolla P, Pinto E Vairo F, de Medeiros PFV, Ribeiro EM, Ribeiro BFR, do Valle FF, Doriqui MJR, Leite CHB, Rocha RM, Moura LMS, Munford V, Galante PAF, Menck CFM, Rogatto SR, Achatz MI. Comprehensive germline mutation analysis and clinical profile in a large cohort of Brazilian xeroderma pigmentosum patients. J Eur Acad Dermatol Venereol 2020; 34:2392-2401. [PMID: 32239545 DOI: 10.1111/jdv.16405] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 03/05/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Xeroderma pigmentosum (XP) patients present a high risk of developing skin cancer and other complications at an early age. This disease is characterized by mutations in the genes related to the DNA repair system. OBJECTIVES To describe the clinical and molecular findings in a cohort of 32 Brazilian individuals who received a clinical diagnosis of XP. METHODS Twenty-seven families were screened for germline variants in eight XP-related genes. RESULTS All patients (N = 32) were diagnosed with bi-allelic germline pathogenic or potentially pathogenic variants, including nine variants previously undescribed. The c.2251-1G>C XPC pathogenic variant, reported as the founder mutation in Comorian and Pakistani patients, was observed in 15 cases in homozygous or compound heterozygous. Seven homozygous patients for POLH/XPV variants developed their symptoms by an average age of 7.7 years. ERCC2/XPD, DDB2/XPE and ERCC5/XPG variants were found in a few patients. Aside from melanoma and non-melanoma skin tumours, a set of patients developed skin sebaceous carcinoma, leiomyosarcoma, angiosarcoma, mucoepidermoid carcinoma, gastric adenocarcinoma and serous ovarian carcinoma. CONCLUSIONS We reported a high frequency of XPC variants in 32 XP Brazilian patients. Nine new variants in XP-related genes, unexpected non-skin cancer lesions and an anticipation of the clinical manifestation in POLH/XPV cases were also described.
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Affiliation(s)
- K M Santiago
- Department of Oncogenetics, A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil.,International Research Center (CIPE), A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil
| | - L P Castro
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, São Paulo, Brazil
| | - J P D Neto
- Department of Skin Cancer, A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil
| | - A F de Nóbrega
- Department of Oncogenetics, A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil.,International Research Center (CIPE), A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil
| | - C A L Pinto
- Department of Pathology, A.C.Camargo Cancer Center, São Paulo, São Paulo, Brazil
| | - P Ashton-Prolla
- Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil.,Department of Genetics, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - F Pinto E Vairo
- Center for Individualized Medicine and Department of Clinical Genomics, Mayo Clinic, Rochester, MN, USA
| | - P F V de Medeiros
- University Hospital Alcides Carneiro, Federal University of Campina Grande, Campina Grande, Paraíba, Brazil
| | - E M Ribeiro
- Associação Cearense de Doenças Genéticas, Fortaleza, Ceará, Brazil
| | - B F R Ribeiro
- Children's Hospital, Secretaria de Estado de Saúde do Acre, Rio Branco, Acre, Brazil
| | - F F do Valle
- Amazonas Federal University, Manaus, Amazonas, Brazil
| | - M J R Doriqui
- Hospital Infantil Dr Juvêncio Mattos, São Luís, Maranhão, Brazil
| | - C H B Leite
- Department of Radiation Oncology, Instituto do Câncer do Ceará, Fortaleza, Ceará, Brazil
| | - R M Rocha
- Gynecology Department, Paulista Medicine School, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
| | - L M S Moura
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, São Paulo, Brazil
| | - V Munford
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, São Paulo, Brazil
| | - P A F Galante
- Molecular Oncology Center, Hospital Sírio-Libanês, São Paulo, São Paulo, Brazil
| | - C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, São Paulo, Brazil
| | - S R Rogatto
- Department of Clinical Genetics, University Hospital, Institute of Regional Health Research, University of Southern Denmark, Vejle, Denmark
| | - M I Achatz
- Centro de Oncologia, Hospital Sírio-Libanês, São Paulo, São Paulo, Brazil
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5
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Castro LP, Sahbatou M, Kehdy FSG, Farias AA, Yurchenko AA, de Souza TA, Rosa RCA, Mendes-Junior CT, Borda V, Munford V, Zanardo ÉA, Chehimi SN, Kulikowski LD, Aquino MM, Leal TP, Tarazona-Santos E, Chaibub SC, Gener B, Calmels N, Laugel V, Sarasin A, Menck CFM. The Iberian legacy into a young genetic xeroderma pigmentosum cluster in central Brazil. Mutat Res 2020; 852:503164. [PMID: 32265042 DOI: 10.1016/j.mrgentox.2020.503164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 02/22/2020] [Accepted: 02/25/2020] [Indexed: 10/24/2022]
Abstract
In central Brazil, in the municipality of Faina (state of Goiás), the small and isolated village of Araras comprises a genetic cluster of xeroderma pigmentosum (XP) patients. The high level of consanguinity and the geographical isolation gave rise to a high frequency of XP patients. Recently, two founder events were identified affecting that community, with two independent mutations at the POLH gene, c.764 + 1 G > A (intron 6) and c.907 C > T; p.Arg303* (exon 8). These deleterious mutations lead to the xeroderma pigmentosum variant syndrome (XP-V). Previous reports identified both mutations in other countries: the intron 6 mutation in six patients (four families) from Northern Spain (Basque Country and Cantabria) and the exon 8 mutation in two patients from different families in Europe, one of them from Kosovo. In order to investigate the ancestry of the XP patients and the age for these mutations at Araras, we generated genotyping information for 22 XP-V patients from Brazil (16), Spain (6) and Kosovo (1). The local genomic ancestry and the shared haplotype segments among the patients showed that the intron 6 mutation at Araras is associated with an Iberian genetic legacy. All patients from Goiás, homozygotes for intron 6 mutation, share with the Spanish patients identical-by-descent (IBD) genomic segments comprising the mutation. The entrance date for the Iberian haplotype at the village was calculated to be approximately 200 years old. This result is in agreement with the historical arrival of Iberian individuals at the Goiás state (BR). Patients from Goiás and the three families from Spain share 1.8 cM (family 14), 1.7 cM (family 15), and a more significant segment of 4.7 cM within family 13. On the other hand, the patients carrying the exon 8 mutation do not share any specific genetic segment, indicating an old genetic distance between them or even no common ancestry.
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Affiliation(s)
- L P Castro
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - M Sahbatou
- Foundation Jean Dausset - CEPH, Paris, France
| | - F S G Kehdy
- Leprosy Laboratory, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - A A Farias
- Human Genome and Stem-Cell Center, Institute of Biosciences, University of São Paulo (USP), Sao Paulo, Brazil; Department of Genetics and Evolutionary Biology, Biosciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - A A Yurchenko
- Inserm U981, Gustave Roussy Cancer Campus, Université Paris Saclay, Villejuif, France
| | - T A de Souza
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - R C A Rosa
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - C T Mendes-Junior
- Department of Chemistry, Forensic and Genomics Research Laboratory, Faculty of Philosophy, Sciences and Letters, University of São Paulo, Ribeirão Preto, Brazil
| | - V Borda
- National Laboratory for Scientific Computation (LNCC), Petropolis, Rio de Janeiro, Brazil
| | - V Munford
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - É A Zanardo
- Cytogenomics Laboratory, Department of Pathology, School of Medicine, University of São Paulo (FMUSP), São Paulo, Brazil
| | - S N Chehimi
- Cytogenomics Laboratory, Department of Pathology, School of Medicine, University of São Paulo (FMUSP), São Paulo, Brazil
| | - L D Kulikowski
- Cytogenomics Laboratory, Department of Pathology, School of Medicine, University of São Paulo (FMUSP), São Paulo, Brazil
| | - M M Aquino
- Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - T P Leal
- Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - E Tarazona-Santos
- Department of Genetics, Ecology and Evolution, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - S C Chaibub
- General Hospital of Goiania, Goiania, Brazil
| | - B Gener
- Osakidetza Basque Health Service, Cruces University Hospital. Department of Genetics, Bizkaia, Spain; Biocruces Bizkaia Health Research Institute, Bizkaia, Spain
| | - N Calmels
- Laboratory of Medical Genetics, Institute of Medical Genetics of Alsace (IGMA), Strasbourg, France
| | - V Laugel
- Laboratory of Medical Genetics, Institute of Medical Genetics of Alsace (IGMA), Strasbourg, France
| | - A Sarasin
- UMR8200 CNRS, Gustave Roussy Institute, University Paris-Saclay, Villejuif, France
| | - C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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Mazzonetto PC, Ariza CB, Ocanha SG, de Souza TA, Ko GM, Menck CFM, Massironi SMG, Porcionatto MA. Mutation in NADPH oxidase 3 (NOX3) impairs SHH signaling and increases cerebellar neural stem/progenitor cell proliferation. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1502-1515. [PMID: 30853403 DOI: 10.1016/j.bbadis.2019.02.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 01/03/2023]
Abstract
Abnormalities in cerebellar structure and function may cause ataxia, a neurological dysfunction of motor coordination. In the course of the present study, we characterized a mutant mouse lineage with an ataxia-like phenotype. We localized the mutation on chromosome 17 and mapped it to position 1534 of the Nox3 gene, resulting in p.Asn64Tyr change. The primary defect observed in Nox3eqlb mice was increased proliferation of cerebellar granule cell precursors (GCPs). cDNA microarray comparing Nox3eqlb and BALB/c neonatal cerebellum revealed changes in the expression of genes involved in the control of cell proliferation. Nox3eqlb GCPs and NSC produce higher amounts of reactive oxygen species (ROS) and upregulate the expression of SHH target genes, such as Gli1-3 and Ccnd1 (CyclinD1). We hypothesize that this new mutation is responsible for an increase in proliferation via stimulation of the SHH pathway. We suggest this mutant mouse lineage as a new model to investigate the role of ROS in neuronal precursor cell proliferation.
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Affiliation(s)
- P C Mazzonetto
- Department of Biochemistry, Laboratory of Neurobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), Brazil
| | - C B Ariza
- Department of Biochemistry, Laboratory of Neurobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), Brazil; Department of General Pathology, Center of Biological Sciences, Universidade Estadual de Londrina (UEL), Brazil
| | - S G Ocanha
- Department of Biochemistry, Laboratory of Neurobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), Brazil
| | - T A de Souza
- Department of Microbiology, Institute of Biomedical Sciences, Universidade de São Paulo (USP), Brazil
| | - G M Ko
- Department of Biochemistry, Laboratory of Neurobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), Brazil
| | - C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, Universidade de São Paulo (USP), Brazil
| | - S M G Massironi
- Department of Immunology, Institute of Biomedical Sciences, Universidade de São Paulo (USP), Brazil
| | - M A Porcionatto
- Department of Biochemistry, Laboratory of Neurobiology, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP), Brazil.
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7
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Munford V, Castro LP, Souto R, Lerner LK, Vilar JB, Quayle C, Asif H, Schuch AP, de Souza TA, Ienne S, Alves FIA, Moura LMS, Galante PAF, Camargo AA, Liboredo R, Pena SDJ, Sarasin A, Chaibub SC, Menck CFM. A genetic cluster of patients with variant xeroderma pigmentosum with two different founder mutations. Br J Dermatol 2017; 176:1270-1278. [PMID: 27664908 DOI: 10.1111/bjd.15084] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2016] [Indexed: 01/04/2023]
Abstract
BACKGROUND Xeroderma pigmentosum (XP) is a rare human syndrome associated with hypersensitivity to sunlight and a high frequency of skin tumours at an early age. We identified a community in the state of Goias (central Brazil), a sunny and tropical region, with a high incidence of XP (17 patients among approximately 1000 inhabitants). OBJECTIVES To identify gene mutations in the affected community and map the distribution of the affected alleles, correlating the mutations with clinical phenotypes. METHODS Functional analyses of DNA repair capacity and cell-cycle responses after ultraviolet exposure were investigated in cells from local patients with XP, allowing the identification of the mutated gene, which was then sequenced to locate the mutations. A specific assay was designed for mapping the distribution of these mutations in the community. RESULTS Skin primary fibroblasts showed normal DNA damage removal but abnormal DNA synthesis after ultraviolet irradiation and deficient expression of the Polη protein, which is encoded by POLH. We detected two different POLH mutations: one at the splice donor site of intron 6 (c.764 +1 G>A), and the other in exon 8 (c.907 C>T, p.Arg303X). The mutation at intron 6 is novel, whereas the mutation at exon 8 has been previously described in Europe. Thus, these mutations were likely brought to the community long ago, suggesting two founder effects for this rare disease. CONCLUSIONS This work describes a genetic cluster involving POLH, and, particularly unexpected, with two independent founder mutations, including one that likely originated in Europe.
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Affiliation(s)
- V Munford
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - L P Castro
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - R Souto
- Secretariat of Health, Goiania, GO, Brazil
| | - L K Lerner
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - J B Vilar
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - C Quayle
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - H Asif
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - A P Schuch
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.,Department of Biochemistry and Molecular Biology, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - T A de Souza
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - S Ienne
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - F I A Alves
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - L M S Moura
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - P A F Galante
- Molecular Oncology Center, Hospital Sírio-Libanês, São Paulo, SP, Brazil
| | - A A Camargo
- Molecular Oncology Center, Hospital Sírio-Libanês, São Paulo, SP, Brazil
| | - R Liboredo
- Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - S D J Pena
- Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - A Sarasin
- UMR 8200 CNRS, Institut Gustave Roussy and University Paris-Saclay, Villejuif, France
| | - S C Chaibub
- General Hospital of Goiania, Goiania, GO, Brazil
| | - C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
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8
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Gomes LR, Vessoni AT, Menck CFM. Three-dimensional microenvironment confers enhanced sensitivity to doxorubicin by reducing p53-dependent induction of autophagy. Oncogene 2015; 34:5329-40. [PMID: 25619836 DOI: 10.1038/onc.2014.461] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 12/02/2014] [Accepted: 12/19/2014] [Indexed: 12/19/2022]
Abstract
Preclinical studies of anticancer drugs are typically performed using cancer cell lines maintained in two-dimensional (2D) cultures, ignoring the influences of the extracellular matrix (ECM) and three-dimensional (3D) microenvironment. In this study, we evaluated the microenvironmental control of human breast cancer cells responses to doxorubicin (DOXO) using the 3D laminin-rich ECM (3D lrECM) cell culture model. Under 3D culture conditions, MCF-7 cells displayed drastic morphological alterations, a decrease in proliferation and elevated sensitivity to DOXO. Interestingly, the chemotherapy-mediated activation of autophagy was compromised in the 3D matrix, suggesting an association between the increased cytotoxicity of DOXO and hindered autophagy induction. Indeed, while chloroquine or ATG5 knockdown potentiated DOXO-induced cell death under the 2D culture conditions, the autophagy inducer rapamycin improved the resistance of 3D-cultured cells to this drug. Moreover, in the monolayer-cultured cells, DOXO treatment led to increases in p53 and DRAM-1 expression, which is a p53-dependent activator of autophagy that functions in response to DNA damage. Conversely, p53 and DRAM-1 expression was impaired in 3D-cultured cells. The knockdown of p53 by shRNA blocked DRAM-1 activation, impaired autophagy induction and sensitized only those cells maintained under 2D conditions to DOXO. In addition, 2D-cultured MDA-MB-231 cells (a p53-mutated breast cancer cell line) not only showed increased sensitivity to DOXO compared with MCF-7 cells but also failed to induce DRAM-1 expression or autophagy. Similar to p53 silencing, DRAM-1 knockdown potentiated DOXO cytotoxicity only in 2D-cultured cells. These results suggest that the 3D tissue microenvironment controls tumor cell sensitivity to DOXO treatment by preventing p53-DRAM-autophagy axis activation.
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Affiliation(s)
- L R Gomes
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - A T Vessoni
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - C F M Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
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9
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Ortolan TG, Menck CFM. UVB-induced cell death signaling is associated with G1-S progression and transcription inhibition in primary human fibroblasts. PLoS One 2013; 8:e76936. [PMID: 24155908 PMCID: PMC3796564 DOI: 10.1371/journal.pone.0076936] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 09/04/2013] [Indexed: 11/19/2022] Open
Abstract
DNA damage induced by ultraviolet (UV) radiation can be removed by nucleotide excision repair through two sub-pathways, one general (GGR) and the other specific for transcribed DNA (TCR), and the processing of unrepaired lesions trigger signals that may lead to cell death. These signals involve the tumor suppressor p53 protein, a central regulator of cell responses to DNA damage, and the E3 ubiquitin ligase Mdm2, that forms a feedback regulatory loop with p53. The involvement of cell cycle and transcription on the signaling to apoptosis was investigated in UVB-irradiated synchronized, DNA repair proficient, CS-B (TCR-deficient) and XP-C (GGR-deficient) primary human fibroblasts. Cells were irradiated in the G1 phase of the cell cycle, with two doses with equivalent levels of apoptosis (low and high), defined for each cell line. In the three cell lines, the low doses of UVB caused only a transient delay in progression to the S phase, whereas the high doses induced permanent cell cycle arrest. However, while accumulation of Mdm2 correlated well with the recovery from transcription inhibition at the low doses for normal and CS-B fibroblasts, for XP-C cells this protein was shown to be accumulated even at UVB doses that induced high levels of apoptosis. Thus, UVB-induced accumulation of Mdm2 is critical for counteracting p53 activation and apoptosis avoidance, but its effect is limited due to transcription inhibition. However, in the case of XP-C cells, an excess of unrepaired DNA damage would be sufficient to block S phase progression, which would signal to apoptosis, independent of Mdm2 accumulation. The data clearly discriminate DNA damage signals that lead to cell death, depending on the presence of UVB-induced DNA damage in replicating or transcribing regions.
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Affiliation(s)
- Tatiana Grohmann Ortolan
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, SP, Brazil
| | - Carlos Frederico M. Menck
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, Sao Paulo, SP, Brazil
- * E-mail:
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10
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Roos WP, Batista LFZ, Naumann SC, Wick W, Weller M, Menck CFM, Kaina B. Apoptosis in malignant glioma cells triggered by the temozolomide-induced DNA lesion O6-methylguanine. Oncogene 2006; 26:186-97. [PMID: 16819506 DOI: 10.1038/sj.onc.1209785] [Citation(s) in RCA: 376] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Methylating drugs such as temozolomide (TMZ) are widely used in the treatment of brain tumours (malignant gliomas). The mechanism of TMZ-induced glioma cell death is unknown. Here, we show that malignant glioma cells undergo apoptosis following treatment with the methylating agents N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and TMZ. Cell death determined by colony formation and apoptosis following methylation is greatly stimulated by p53. Transfection experiments with O(6)-methylguanine-DNA methyltransferase (MGMT) and depletion of MGMT by O(6)-benzylguanine showed that, in gliomas, the apoptotic signal originates from O(6)-methylguanine (O(6)MeG) and that repair of O(6)MeG by MGMT prevents apoptosis. We further demonstrate that O(6)MeG-triggered apoptosis requires Fas/CD95/Apo-1 receptor activation in p53 non-mutated glioma cells, whereas in p53 mutated gliomas the same DNA lesion triggers the mitochondrial apoptotic pathway. This occurs less effectively via Bcl-2 degradation and caspase-9, -2, -7 and -3 activation. O(6)MeG-triggered apoptosis in gliomas is a late response (occurring >120 h after treatment) that requires extensive cell proliferation. Stimulation of cell cycle progression by the Pasteurella multocida toxin promoted apoptosis whereas serum starvation attenuated it. O(6)MeG-induced apoptosis in glioma cells was preceded by the formation of DNA double-strand breaks (DSBs), as measured by gammaH2AX formation. Glioma cells mutated in DNA-PK(cs), which is involved in non-homologous end-joining, were more sensitive to TMZ-induced apoptosis, supporting the involvement of DSBs as a downstream apoptosis triggering lesion. Overall, the data demonstrate that cell death induced by TMZ in gliomas is due to apoptosis and that determinants of sensitivity of gliomas to TMZ are MGMT, p53, proliferation rate and DSB repair.
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Affiliation(s)
- W P Roos
- Department of Toxicology, University of Mainz, Mainz, Germany
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11
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Nascimento ALTO, Ko AI, Martins EAL, Monteiro-Vitorello CB, Ho PL, Haake DA, Verjovski-Almeida S, Hartskeerl RA, Marques MV, Oliveira MC, Menck CFM, Leite LCC, Carrer H, Coutinho LL, Degrave WM, Dellagostin OA, El-Dorry H, Ferro ES, Ferro MIT, Furlan LR, Gamberini M, Giglioti EA, Góes-Neto A, Goldman GH, Goldman MHS, Harakava R, Jerônimo SMB, Junqueira-de-Azevedo ILM, Kimura ET, Kuramae EE, Lemos EGM, Lemos MVF, Marino CL, Nunes LR, de Oliveira RC, Pereira GG, Reis MS, Schriefer A, Siqueira WJ, Sommer P, Tsai SM, Simpson AJG, Ferro JA, Camargo LEA, Kitajima JP, Setubal JC, Van Sluys MA. Comparative genomics of two Leptospira interrogans serovars reveals novel insights into physiology and pathogenesis. J Bacteriol 2004; 186:2164-72. [PMID: 15028702 PMCID: PMC374407 DOI: 10.1128/jb.186.7.2164-2172.2004] [Citation(s) in RCA: 312] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in accidental hosts, including humans. Complete genome sequencing of Leptospira interrogans serovar Copenhageni and comparative analysis with the available Leptospira interrogans serovar Lai genome reveal that despite overall genetic similarity there are significant structural differences, including a large chromosomal inversion and extensive variation in the number and distribution of insertion sequence elements. Genome sequence analysis elucidates many of the novel aspects of leptospiral physiology relating to energy metabolism, oxygen tolerance, two-component signal transduction systems, and mechanisms of pathogenesis. A broad array of transcriptional regulation proteins and two new families of afimbrial adhesins which contribute to host tissue colonization in the early steps of infection were identified. Differences in genes involved in the biosynthesis of lipopolysaccharide O side chains between the Copenhageni and Lai serovars were identified, offering an important starting point for the elucidation of the organism's complex polysaccharide surface antigens. Differences in adhesins and in lipopolysaccharide might be associated with the adaptation of serovars Copenhageni and Lai to different animal hosts. Hundreds of genes encoding surface-exposed lipoproteins and transmembrane outer membrane proteins were identified as candidates for development of vaccines for the prevention of leptospirosis.
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Affiliation(s)
- A L T O Nascimento
- Centro de Biotecnologia, Instituto Butantan, Universidade de São Paulo, São Paulo, Brazil.
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12
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Chiganças V, Batista LFZ, Brumatti G, Amarante-Mendes GP, Yasui A, Menck CFM. Photorepair of RNA polymerase arrest and apoptosis after ultraviolet irradiation in normal and XPB deficient rodent cells. Cell Death Differ 2002; 9:1099-107. [PMID: 12232798 DOI: 10.1038/sj.cdd.4401072] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2002] [Revised: 03/01/2002] [Accepted: 05/03/2002] [Indexed: 11/08/2022] Open
Abstract
Cyclobutane pyrimidine dimers (CPDs) are directly involved in signaling for UV-induced apoptosis in mammalian cells. Failure to remove these lesions, specially those located at actively expressing genes, is critical, as cells defective in transcription coupled repair have increased apoptotic levels. Thus, the blockage of RNA synthesis by lesions is an important candidate event triggering off active cell death. In this work, wild-type and XPB mutated Chinese hamster ovary (CHO) cells expressing a marsupial photolyase, that removes specifically CPDs from the damaged DNA, were generated, in order to investigate the importance of this lesion in both RNA transcription blockage and apoptotic induction. Photorepair strongly recovers RNA synthesis in wild-type CHO cell line, although the resumption of transcription is decreased in XPB deficient cells. This recovery is accompanied by the prevention of cells entering into apoptosis. These results demonstrate that marsupial photolyase has access to CPDs blocking RNA synthesis in vivo, and this may be affected by the presence of a mutated XPB protein.
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Affiliation(s)
- V Chiganças
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo 05508-900, SP, Brazil
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13
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Magalhaes GS, Muotri AR, Marchetto MCN, Menck CFM, Ventura AM. An adenovirus vector containing the suicide gene thymidine kinase for a broad application in cancer gene therapy. Mem Inst Oswaldo Cruz 2002; 97:547-52. [PMID: 12118289 DOI: 10.1590/s0074-02762002000400018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Treatment of cancer using gene therapy is based on adding a property to the cell leading to its elimination. One possibility is the use of suicide genes that code for enzymes that transform a pro-drug into a cytotoxic product. The most extensively used is the herpes simplex virus thymidine kinase (TK) gene, followed by administration of the antiviral drug ganciclovir (GCV). The choice of the promoter to drive the transcription of a transgene is one of the determinants of a given transfer vector usefulness, as different promoters show different efficiencies depending on the target cell type. In the experiments presented here, we report the construction of a recombinant adenovirus carrying TK gene (Ad-TK) driven by three strong promoters (P CMV IE, SV40 and EN1) and its effectiveness in two cell types. Human HeLa and mouse CCR2 tumor cells were transduced with Ad-TK and efficiently killed after addition of GCV. We could detect two sizes of transcripts of TK gene, one derived from the close together P CMV IE/SV40 promoters and the other from the 1.5 Kb downstream EN1 promoter. The relative amounts of these transcripts were different in each cell type thus indicating a higher flexibility of this system.
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Affiliation(s)
- G S Magalhaes
- Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, 05508-900, Brasil
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14
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da Silva ACR, Ferro JA, Reinach FC, Farah CS, Furlan LR, Quaggio RB, Monteiro-Vitorello CB, Van Sluys MA, Almeida NF, Alves LMC, do Amaral AM, Bertolini MC, Camargo LEA, Camarotte G, Cannavan F, Cardozo J, Chambergo F, Ciapina LP, Cicarelli RMB, Coutinho LL, Cursino-Santos JR, El-Dorry H, Faria JB, Ferreira AJS, Ferreira RCC, Ferro MIT, Formighieri EF, Franco MC, Greggio CC, Gruber A, Katsuyama AM, Kishi LT, Leite RP, Lemos EGM, Lemos MVF, Locali EC, Machado MA, Madeira AMBN, Martinez-Rossi NM, Martins EC, Meidanis J, Menck CFM, Miyaki CY, Moon DH, Moreira LM, Novo MTM, Okura VK, Oliveira MC, Oliveira VR, Pereira HA, Rossi A, Sena JAD, Silva C, de Souza RF, Spinola LAF, Takita MA, Tamura RE, Teixeira EC, Tezza RID, Trindade dos Santos M, Truffi D, Tsai SM, White FF, Setubal JC, Kitajima JP. Comparison of the genomes of two Xanthomonas pathogens with differing host specificities. Nature 2002; 417:459-63. [PMID: 12024217 DOI: 10.1038/417459a] [Citation(s) in RCA: 782] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The genus Xanthomonas is a diverse and economically important group of bacterial phytopathogens, belonging to the gamma-subdivision of the Proteobacteria. Xanthomonas axonopodis pv. citri (Xac) causes citrus canker, which affects most commercial citrus cultivars, resulting in significant losses worldwide. Symptoms include canker lesions, leading to abscission of fruit and leaves and general tree decline. Xanthomonas campestris pv. campestris (Xcc) causes black rot, which affects crucifers such as Brassica and Arabidopsis. Symptoms include marginal leaf chlorosis and darkening of vascular tissue, accompanied by extensive wilting and necrosis. Xanthomonas campestris pv. campestris is grown commercially to produce the exopolysaccharide xanthan gum, which is used as a viscosifying and stabilizing agent in many industries. Here we report and compare the complete genome sequences of Xac and Xcc. Their distinct disease phenotypes and host ranges belie a high degree of similarity at the genomic level. More than 80% of genes are shared, and gene order is conserved along most of their respective chromosomes. We identified several groups of strain-specific genes, and on the basis of these groups we propose mechanisms that may explain the differing host specificities and pathogenic processes.
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Affiliation(s)
- A C R da Silva
- Departamento de Bioquímica, Instituto de Química, Av. Prof. Lineu Prestes 748, São Paulo, SP, Brazil
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15
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Van Sluys MA, Monteiro-Vitorello CB, Camargo LEA, Menck CFM, Da Silva ACR, Ferro JA, Oliveira MC, Setubal JC, Kitajima JP, Simpson AJ. Comparative genomic analysis of plant-associated bacteria. Annu Rev Phytopathol 2002; 40:169-189. [PMID: 12147758 DOI: 10.1146/annurev.phyto.40.030402.090559] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This review deals with a comparative analysis of seven genome sequences from plant-associated bacteria. These are the genomes of Agrobacterium tumefaciens, Mesorhizobium loti, Sinorhizobium meliloti, Xanthomonas campestris pv campestris, Xanthomonas axonopodis pv citri, Xylella fastidiosa, and Ralstonia solanacearum. Genome structure and the metabolism pathways available highlight the compromise between the genome size and lifestyle. Despite the recognized importance of the type III secretion system in controlling host compatibility, its presence is not universal in all necrogenic pathogens. Hemolysins, hemagglutinins, and some adhesins, previously reported only for mammalian pathogens, are present in most organisms discussed. Different numbers and combinations of cell wall degrading enzymes and genes to overcome the oxidative burst generally induced by the plant host are characterized in these genomes. A total of 19 genes not involved in housekeeping functions were found common to all these bacteria.
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Affiliation(s)
- M A Van Sluys
- Depto de Botânica, Instituto de Biociências, Universidade de São Paulo, Brazil.
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