Function of TALE1Xam in cassava bacterial blight: a transcriptomic approach

Xanthomonas axonopodis pv. manihotis (Xam) is a gram negative bacteria causing the Cassava Bacterial Blight (CBB) in Manihot esculenta Crantz. Cassava represents one of the most important sources of carbohydrates for around one billion people around the world as well as a source of energy due to its high starch levels content. The CBB disease represents an important limitation for cassava massive production and little is known about this pathosystem. Bacterial pathogenicity often relies on the injection in eucaryotic host cells of effector proteins via a type III secretion system (TTSS). Between all the type III effectors described up to now, Transcription Activator-Like Type III effectors (TALE) appear as particularly interesting. Once injected into the plant cell, TALEs go into the nucleus cell and modulate the expression of target host genes to the benefit of the invading bacteria by interacting directly with plant DNA. In Xam, only one gene belonging to this family has been functionally studied so far. It consists on TALE1Xam. This work aim to identify cassava genes whose expression will be modified upon the presence of TALE1Xam. By means of a microarray containing 5700 cassava genes, the TALE code and two Hi-RNAseq lanes, we seek out direct TALE1Xam target genes. Hence, through functional qRT validation, specific artificial TALEs design and statistical analyses between cassava plants challenged with Xam Δ TALE1Xam vs. Xam + TALE1Xam, we proposed that TALE1Xam is potentially interacting with a Heat Shock Transcription Factor B3. Moreover we argue that this gene is responsible of the susceptibility during Xam infection. Furthermore this work represents the first complete transcriptomic approach done in the cassava/Xam interaction and open huge possibilities to understand and study CBB.

• Autores: Muñoz Bodnar, Alejandra
• Tipo de recurso: Doctoral thesis
• Fecha de publicación: 2012
• Institución: Universidad Nacional de Colombia
• Repositorio: Universidad Nacional de Colombia
• Idioma: spa
• OAI Identifier: oai:repositorio.unal.edu.co:unal/20576
• Acceso en línea: https://repositorio.unal.edu.co/handle/unal/20576; http://bdigital.unal.edu.co/11222/
• Palabra clave: 51 Matemáticas / Mathematics; 57 Ciencias de la vida; Biología / Life sciences; biology; 63 Agricultura y tecnologías relacionadas / Agriculture; CBB; Xanthomonas; TAL effector; Heat Shock Transcription factor; RNAseq; Cassava; Añublo bacteriano; Efectores tipo TAL; Factor de transcripción; RNAseq; Yuca
• Rights: openAccess
• License: Atribución-NoComercial 4.0 Internacional