• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Doctoral Thesis
DOI
https://doi.org/10.11606/T.11.2018.tde-08102018-163721
Document
Author
Full name
Bruna Laís Merlin
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
Piracicaba, 2018
Supervisor
Committee
Cônsoli, Fernando Luis (President)
Camilo, Cesar Moises
Carvalho, Renato Assis de
Rossi, Guilherme Duarte
Wulff, Nelson Arno
Title in Portuguese
Análise transcricional da interação Cotesia flavipes Cameron (Hymenoptera: Braconidae) - Diatraea saccharalis (F.) (Lepidoptera: Crambidae) e exploração de fatores de virulência associados ao parasitismo na transgenia de plantas
Keywords in Portuguese
Bracovirus
Exploração Biotecnológica
Regulação hospedeira
Transgenia
Abstract in Portuguese
Ao longo do processo evolutivo, parasitoides desenvolveram inúmeras estratégias para a colonização de seus hospedeiros, resultando em mecanismos específicos de regulação. Endoparasitoides cenobiontes depositam seus ovos no hospedeiro e manipulam sua fisiologia e suas repostas imunológicas, a fim de tornar o hospedeiro um ambiente seguro e nutricionalmente adequado para o desenvolvimento do imaturo. A associação de parasitoides das famílias Braconidae e Ichneumonidae com vírus da família Polydnaviridae e sua injeção no hospedeiro configuram-se como um dos principais mecanismos de regulação utilizados durante o parasitismo, devido sua ação sobre a expressão de genes do hospedeiro. O conjunto diverso de fatores maternos e larvais apresentados por parasitoides pode apresentar potencial biotecnológico no controle de pragas, que busca por novos nichos de exploração. Apesar disso, a especificidade das interações hospedeiro - parasitoide limita a exploração de eventos que utilizam tais fatores de virulência, baseada na necessidade de táticas que apresentem ação sobre maior número de espécies-praga. Dessa forma, a presente tese teve por objetivo identificar fatores de virulência expressos durante a interação Cotesia flavipes Cameron (Hymenoptera: Braconidae) - Diatraea saccharalis (F.) (Lepidoptera: Crambidae), buscando a identificação de fatores com potencial biotecnológico, e identificar vias metabólicas do hospedeiro alvos de regulação, buscando por genes-alvos de controle. Além disso, essa tese buscou avaliar o potencial biotecnológico de um fator de virulência (CfHTIF) pertencente ao vírus simbionte de C. flavipes e de um fator de virulência larval (TnQuit) expresso por teratócitos associados a Toxoneuron nigriceps (Viereck) (Hymenoptera: Braconidae) contra hospedeiros incomuns. O parasitismo e a injeção de fatores maternos por C. flavipes resultou na regulação de inúmeras vias metabólicas de D. saccharalis, principalmente relacionadas ao controle do sistema endócrino e do sistema imunológico e identificou a expressão de genes virais e larvais associados a C. flavipes. Plantas transformadas com o fator de virulência TnQuit apresentaram efeitos na sobrevivência e no desenvolvimento dos hospedeiros não-permissivos de hábito mastigador, Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), Spodoptera albula (Walker) (Lepidoptera: Noctuidae) e Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), minador, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), e sugador, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), enquanto que o gene viral CfHTIF interferiu nas eficiências de conversão do alimento ingerido e digerido de S. albula, mas não de S. frugiperda.
Title in English
Transcriptional analysis of the interaction Cotesia flavipes Cameron (Hymenoptera: Braconidae) - Diatraea saccharalis (F.) (Lepidoptera: Crambidae) and the exploration of virulence factors associated with parasitization in plant transgenesis
Keywords in English
Biotechnology exploration
Bracovirus
Host regulation
Transgenesis
Abstract in English
Parasitoids developed many strategies for colonization of their hosts during the evolution of associations with their hosts, which resulted in the development of specific mechanisms of host regulation. Koinobiont endoparasitoids deposit their eggs into the host and manipulate the host´s physiology and immune responses in order to turn the host a safe and nutritionally suitable environment for parasitoid immature development. The association of parasitoids belonging to Braconidae and Ichneumonidae with virus of the family Polydnaviridae, which are injected in the host, constitutes one of the main mechanisms of regulation used during the parasitization due to viral regulation of the host gene expression. The diverse set of maternal and larval-derived factors produced by parasitoids may have biotechnological potential for pest control. Nevertheless, the specificity of the host - parasitoid interactions are thought to limit the exploration of events that use such virulence factors, as a consequence on the need of successful tactics for a large number of pest species. Thus, we aimed to identify the virulence factors expressed during the interaction Cotesia flavipes Cameron (Hymenoptera: Braconidae) - Diatraea saccharalis (F.) (Lepidoptera: Crambidae) to identify factors with biotechnological potential and to identify targets of regulation that could aid on the development of additional control tactics. In addition, we evaluated the biotechnological potential of a virulence factor (CfHTIF) belonging to the symbiont virus of C. flavipes and a larval virulence factor (TnQuit) expressed by teratocytes associated to Toxoneuron nigriceps (Viereck) (Hymenoptera: Braconidae) against non-host species. Parasitization and pseudoparasitization of D. saccharalis larvae by C. flavipes resulted in the regulation of several metabolic pathways, particularly those related to the endocrine and immune systems. We also characterized the transcriptome of C. flavipes and of associated bracovirus in parasitized and pseudoparasitized hosts. Plants transformed with the TnQuit virulence factor affected survival and development of the non-permissive hosts Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae), Spodoptera albula (Walker) (Lepidoptera: Noctuidae) and Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and the number of developing adults of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). CfHTIF-transgenic plants affected the efficiency of conversion of the digested and ingested food of S. albula larvae, but not of S. frugiperda larvae.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Release Date
2022-10-14
Publishing Date
2018-10-25
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2021. All rights reserved.