|
| Status |
Public on Sep 01, 2007 |
| Title |
Global gene expression analysis of the phytopathogen Xylella fastidiosa at low iron availability |
| Organism |
Xylella fastidiosa |
| Experiment type |
Expression profiling by array
|
| Summary |
Xylella fastidiosa is the etiologic agent of a wide range of plant diseases including citrus variegated chlorosis (CVC), a major threat to the Brazilian citrus industry. Genome sequences of several strains of this phytopathogen are accessible, enabling large-scale functional studies. Transcript levels in different iron availabilities were assessed with DNA microarrays representing 2608 (91.6%) coding sequences (CDS) of X. fastidiosa CVC strain 9a5c. When treated with the iron chelator 2,2-dipyridyl, 193 CDS were considered as up-regulated and 216 as down-regulated. In the presence of 100uM of ferric pyrophosphate, 218 and 256 CDS were considered as up- and down-regulated, respectively. Differential expression for a subset of 44 CDS was further evaluated by reverse transcription - quantitative PCR that showed a Pearson correlation of 0.77 with array results. The CDS differentially expressed upon the iron concentration shift participate in diverse cellular functions. Many CDS involved with regulatory functions, pathogenicity and cell structure, were modulated in both conditions tested suggesting that major changes in cell architecture and metabolism occur when X. fastidiosa cells are exposed to extreme variations in iron concentration. Interestingly, the modulated CDS include those related to colicin V-like bacteriocin synthesis and secretion and to pili/fimbriae functions. We also investigated the contribution of the ferric uptake regulator Fur to the iron regulon of X. fastidiosa. The promoter regions of strain 9a5c genome were screened for putative Fur boxes and candidates were analyzed by electrophoretic mobility shift assays. Taken together, our data support the hypothesis that Fur is not solely responsible for the modulation of the iron regulon of X. fastidiosa and present novel evidence for iron regulation of pathogenicity determinants.
Keywords: stress response; response to iron-depleted condition
|
| |
|
| Overall design |
Direct comparison between low iron content (200uM 2,2-dipyridyl) and control condition. Hybridizations are dye-swaped. There are 2 biological replicates (independent harvest) and 2 technical replicates of each array (L - left and R - right).
|
| |
|
| Citation(s) |
18223091 |
| |
| Submission date |
Sep 20, 2006 |
| Last update date |
Jul 26, 2013 |
| Contact name |
Ricardo Z.N. Vêncio |
| Organization name |
Universidade de São Paulo
|
| Department |
Computing and Mathematics Department
|
| Lab |
http://labpib.fmrp.usp.br
|
| Street address |
Av. Bandeirantes, 3900
|
| City |
Ribeirao Preto |
| State/province |
SP |
| ZIP/Postal code |
14049-900 |
| Country |
Brazil |
| |
|
| Platforms (1) |
| GPL2708 |
Xylella USP microarray v2 (Koide et al. 2004 J.Bact.) |
|
| Samples (22)
|
|
| Relations |
| BioProject |
PRJNA97311 |
Less...
More...