Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis

Detalhes bibliográficos
Autor(a) principal: Ferreira, Ludmila R.p. [UNIFESP]
Data de Publicação: 2008
Outros Autores: Dossin, Fernando De M. [UNIFESP], Ramos, Thiago Cesar Prata [UNIFESP], Freymüller-Haapalainen, Edna [UNIFESP], Schenkman, Sergio [UNIFESP]
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UNIFESP
dARK ID: ark:/48912/001300000b3k8
DOI: 10.1590/S0001-37652008000100011
Texto Completo: http://dx.doi.org/10.1590/S0001-37652008000100011
http://repositorio.unifesp.br/handle/11600/4271
Resumo: The differentiation of proliferating epimastigote forms of Trypanosoma cruzi , the protozoan parasite that causes Chagas disease, into the infective and non-proliferating metacyclic forms can be reproduced in the laboratory by incubating the cells in a chemically-defined medium that mimics the urine of the insect vector. Epimastigotes have a spherical nucleus, a flagellum protruding from the middle of the protozoan cell, and a disk-shaped kinetoplast - an organelle that corresponds to the mitochondrial DNA. Metacyclic trypomastigotes have an elongated shape with the flagellum protruding from the posterior portion of the cell and associated with a spherical kinetoplast. Here we describe the morphological events of this transformation and characterize a novel intermediate stage by three-dimensional reconstruction of electron microscope serial sections. This new intermediate stage is characterized by a kinetoplast compressing an already elongated nucleus, indicating that metacyclogenesis involves active movements of the flagellar structure relative to the cell body. As transcription occurs more intensely in proliferating epimastigotes than in metacyclics, we also examined the presence of RNA polymerase II and measured transcriptional activity during the differentiation process. Both the presence of the enzyme and transcriptional activity remain unchanged during all steps of metacyclogenesis. RNA polymerase II levels and transcriptional activity only decrease after metacyclics are formed. We suggest that transcription is required during the epimastigote-to-metacyclic trypomastigote differentiation process, until the kinetoplast and flagellum reach the posterior position of the parasites in the infective form.
id UFSP_f5c282ca02d48a767542e9adfa19dc31
oai_identifier_str oai:repositorio.unifesp.br/:11600/4271
network_acronym_str UFSP
network_name_str Repositório Institucional da UNIFESP
repository_id_str 3465
spelling Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesisTrypanosoma cruzimetacyclogenesistranscriptionRNA polymerase IITrypanosoma cruzimetaciclogênesetranscriçãoRNA polimerase IIThe differentiation of proliferating epimastigote forms of Trypanosoma cruzi , the protozoan parasite that causes Chagas disease, into the infective and non-proliferating metacyclic forms can be reproduced in the laboratory by incubating the cells in a chemically-defined medium that mimics the urine of the insect vector. Epimastigotes have a spherical nucleus, a flagellum protruding from the middle of the protozoan cell, and a disk-shaped kinetoplast - an organelle that corresponds to the mitochondrial DNA. Metacyclic trypomastigotes have an elongated shape with the flagellum protruding from the posterior portion of the cell and associated with a spherical kinetoplast. Here we describe the morphological events of this transformation and characterize a novel intermediate stage by three-dimensional reconstruction of electron microscope serial sections. This new intermediate stage is characterized by a kinetoplast compressing an already elongated nucleus, indicating that metacyclogenesis involves active movements of the flagellar structure relative to the cell body. As transcription occurs more intensely in proliferating epimastigotes than in metacyclics, we also examined the presence of RNA polymerase II and measured transcriptional activity during the differentiation process. Both the presence of the enzyme and transcriptional activity remain unchanged during all steps of metacyclogenesis. RNA polymerase II levels and transcriptional activity only decrease after metacyclics are formed. We suggest that transcription is required during the epimastigote-to-metacyclic trypomastigote differentiation process, until the kinetoplast and flagellum reach the posterior position of the parasites in the infective form.A diferenciação de formas epimastigotas (proliferativas) do Trypanosoma cruzi, parasita protozoário causador da doença de Chagas, em formas metacíclicas tripomastigotas (infectivas e não proliferativas), pode ser reproduzida em laboratório incubando-se as células em um meio quimicamente definido que imita a urina do inseto vetor deste parasita. Os epimastigotas têm um núcleo esférico, o flagelo se projeta da metade do corpo do protozoário e o cinetoplasto (organela que possui o DNA mitocondrial) possui formato de disco. Os tripomastigotas metacíclicos têm um núcleo alongado com o flagelo emergindo da extremidade posterior da célula associado ao cinetoplasto esférico. Neste trabalho descrevemos as mudanças morfológicas que ocorrem durante essa transformação e caracterizamos uma nova forma intermediária do parasita usando reconstrução tridimensional de cortes seriados, visualizados por microscopia eletrônica de transmissão. Essa nova forma intermediária é caracterizada pela compressão do cinetoplasto contra o núcleo alongado, indicando que a metaciclogênese envolve movimentos ativos do cinetoplasto associado à estrutura flagelar em relação ao corpo celular. Como tripomastigotas metacíclicos transcrevem menos que as formas epimastigotas proliferativas, verificamos a presença da RNA polimerase II e medimos a atividade transcricional durante o processo de diferenciação. A presença da enzima e a atividade transcricional permanecem inalteradas durante todas as etapas da metaciclogênese, desaparecendo apenas quando as formas metacíclicas são formadas. Sugerimos que a diferenciação requer uma atividade transcricional, necessária para uma intensa remodelação da célula, que acontece até o cinetoplasto e o flagelo atingirem uma posição posterior do corpo do tripomastigota metacíclico.Universidade Federal de São Paulo (UNIFESP) Departamento de Microbiologia, Imunologia e ParasitologiaUniversidade Federal de São Paulo (UNIFESP) Centro de Microscopia EletrônicaUNIFESP, Depto. de Microbiologia, Imunologia e ParasitologiaUNIFESP, Centro de Microscopia EletrônicaSciELOFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Academia Brasileira de CiênciasUniversidade Federal de São Paulo (UNIFESP)Ferreira, Ludmila R.p. [UNIFESP]Dossin, Fernando De M. [UNIFESP]Ramos, Thiago Cesar Prata [UNIFESP]Freymüller-Haapalainen, Edna [UNIFESP]Schenkman, Sergio [UNIFESP]2015-06-14T13:38:26Z2015-06-14T13:38:26Z2008-03-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersion157-166application/pdfhttp://dx.doi.org/10.1590/S0001-37652008000100011Anais da Academia Brasileira de Ciências. Academia Brasileira de Ciências, v. 80, n. 1, p. 157-166, 2008.10.1590/S0001-37652008000100011S0001-37652008000100011.pdf0001-3765S0001-37652008000100011http://repositorio.unifesp.br/handle/11600/4271WOS:000254392700011ark:/48912/001300000b3k8engAnais da Academia Brasileira de Ciênciasinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UNIFESPinstname:Universidade Federal de São Paulo (UNIFESP)instacron:UNIFESP2024-07-29T09:07:41Zoai:repositorio.unifesp.br/:11600/4271Repositório InstitucionalPUBhttp://www.repositorio.unifesp.br/oai/requestbiblioteca.csp@unifesp.bropendoar:34652024-12-11T20:08:29.919902Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)false
dc.title.none.fl_str_mv Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
title Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
spellingShingle Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
Ferreira, Ludmila R.p. [UNIFESP]
Trypanosoma cruzi
metacyclogenesis
transcription
RNA polymerase II
Trypanosoma cruzi
metaciclogênese
transcrição
RNA polimerase II
Ferreira, Ludmila R.p. [UNIFESP]
Trypanosoma cruzi
metacyclogenesis
transcription
RNA polymerase II
Trypanosoma cruzi
metaciclogênese
transcrição
RNA polimerase II
title_short Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
title_full Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
title_fullStr Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
title_full_unstemmed Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
title_sort Active transcription and ultrastructural changes during Trypanosoma cruzi metacyclogenesis
author Ferreira, Ludmila R.p. [UNIFESP]
author_facet Ferreira, Ludmila R.p. [UNIFESP]
Ferreira, Ludmila R.p. [UNIFESP]
Dossin, Fernando De M. [UNIFESP]
Ramos, Thiago Cesar Prata [UNIFESP]
Freymüller-Haapalainen, Edna [UNIFESP]
Schenkman, Sergio [UNIFESP]
Dossin, Fernando De M. [UNIFESP]
Ramos, Thiago Cesar Prata [UNIFESP]
Freymüller-Haapalainen, Edna [UNIFESP]
Schenkman, Sergio [UNIFESP]
author_role author
author2 Dossin, Fernando De M. [UNIFESP]
Ramos, Thiago Cesar Prata [UNIFESP]
Freymüller-Haapalainen, Edna [UNIFESP]
Schenkman, Sergio [UNIFESP]
author2_role author
author
author
author
dc.contributor.none.fl_str_mv Universidade Federal de São Paulo (UNIFESP)
dc.contributor.author.fl_str_mv Ferreira, Ludmila R.p. [UNIFESP]
Dossin, Fernando De M. [UNIFESP]
Ramos, Thiago Cesar Prata [UNIFESP]
Freymüller-Haapalainen, Edna [UNIFESP]
Schenkman, Sergio [UNIFESP]
dc.subject.por.fl_str_mv Trypanosoma cruzi
metacyclogenesis
transcription
RNA polymerase II
Trypanosoma cruzi
metaciclogênese
transcrição
RNA polimerase II
topic Trypanosoma cruzi
metacyclogenesis
transcription
RNA polymerase II
Trypanosoma cruzi
metaciclogênese
transcrição
RNA polimerase II
description The differentiation of proliferating epimastigote forms of Trypanosoma cruzi , the protozoan parasite that causes Chagas disease, into the infective and non-proliferating metacyclic forms can be reproduced in the laboratory by incubating the cells in a chemically-defined medium that mimics the urine of the insect vector. Epimastigotes have a spherical nucleus, a flagellum protruding from the middle of the protozoan cell, and a disk-shaped kinetoplast - an organelle that corresponds to the mitochondrial DNA. Metacyclic trypomastigotes have an elongated shape with the flagellum protruding from the posterior portion of the cell and associated with a spherical kinetoplast. Here we describe the morphological events of this transformation and characterize a novel intermediate stage by three-dimensional reconstruction of electron microscope serial sections. This new intermediate stage is characterized by a kinetoplast compressing an already elongated nucleus, indicating that metacyclogenesis involves active movements of the flagellar structure relative to the cell body. As transcription occurs more intensely in proliferating epimastigotes than in metacyclics, we also examined the presence of RNA polymerase II and measured transcriptional activity during the differentiation process. Both the presence of the enzyme and transcriptional activity remain unchanged during all steps of metacyclogenesis. RNA polymerase II levels and transcriptional activity only decrease after metacyclics are formed. We suggest that transcription is required during the epimastigote-to-metacyclic trypomastigote differentiation process, until the kinetoplast and flagellum reach the posterior position of the parasites in the infective form.
publishDate 2008
dc.date.none.fl_str_mv 2008-03-01
2015-06-14T13:38:26Z
2015-06-14T13:38:26Z
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.uri.fl_str_mv http://dx.doi.org/10.1590/S0001-37652008000100011
Anais da Academia Brasileira de Ciências. Academia Brasileira de Ciências, v. 80, n. 1, p. 157-166, 2008.
10.1590/S0001-37652008000100011
S0001-37652008000100011.pdf
0001-3765
S0001-37652008000100011
http://repositorio.unifesp.br/handle/11600/4271
WOS:000254392700011
dc.identifier.dark.fl_str_mv ark:/48912/001300000b3k8
url http://dx.doi.org/10.1590/S0001-37652008000100011
http://repositorio.unifesp.br/handle/11600/4271
identifier_str_mv Anais da Academia Brasileira de Ciências. Academia Brasileira de Ciências, v. 80, n. 1, p. 157-166, 2008.
10.1590/S0001-37652008000100011
S0001-37652008000100011.pdf
0001-3765
S0001-37652008000100011
WOS:000254392700011
ark:/48912/001300000b3k8
dc.language.iso.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv Anais da Academia Brasileira de Ciências
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv 157-166
application/pdf
dc.publisher.none.fl_str_mv Academia Brasileira de Ciências
publisher.none.fl_str_mv Academia Brasileira de Ciências
dc.source.none.fl_str_mv reponame:Repositório Institucional da UNIFESP
instname:Universidade Federal de São Paulo (UNIFESP)
instacron:UNIFESP
instname_str Universidade Federal de São Paulo (UNIFESP)
instacron_str UNIFESP
institution UNIFESP
reponame_str Repositório Institucional da UNIFESP
collection Repositório Institucional da UNIFESP
repository.name.fl_str_mv Repositório Institucional da UNIFESP - Universidade Federal de São Paulo (UNIFESP)
repository.mail.fl_str_mv biblioteca.csp@unifesp.br
_version_ 1822219216754835456
dc.identifier.doi.none.fl_str_mv 10.1590/S0001-37652008000100011