1 research outputs found
Xylella fastidiosa : An in vivo system to study possible survival strategies within citrus xylem vessels based on global gene expression analysis
Abstract Xylella fastidiosa inhabits the plant xylem, a nutrient-poor
environment, so that mechanisms to sense and respond to adverse
environmental conditions are extremely important for bacterial survival
in the plant host. Although the complete genome sequences of different
Xylella strains have been determined, little is known about stress
responses and gene regulation in these organisms. In this work, a DNA
microarray was constructed containing 2,600 ORFs identified in the
genome sequencing project of Xylella fastidiosa 9a5c strain, and used
to check global gene expression differences in the bacteria when it is
infecting a symptomatic and a tolerant citrus tree. Different patterns
of expression were found in each variety, suggesting that bacteria are
responding differentially according to each plant xylem environment.
The global gene expression profile was determined and several genes
related to bacterial survival in stressed conditions were found to be
differentially expressed between varieties, suggesting the involvement
of different strategies for adaptation to the environment. The
expression pattern of some genes related to the heat shock response,
toxin and detoxification processes, adaptation to atypical conditions,
repair systems as well as some regulatory genes are discussed in this
paper. DNA microarray proved to be a powerful technique for global
transcriptome analyses. This is one of the first studies of Xylella
fastidiosa gene expression in vivo which helped to increase insight
into stress responses and possible bacterial survival mechanisms in the
nutrient-poor environment of xylem vessels