Bioinformatics analysis of defense associated transcriptional networks
Our study here
in Bioinformatics pivots around GeneChip technology-coupled with parallel expression
analysis. In collaboration with Syngenta
we utilize expression analysis to identify gene activity patterns associated
with plant immune responses to pathogenic microorganisms such as Peronospera
Parasitica and Pseudomonas Syringae. This study, performed by many
scientists in the lab, helps to achieve a more global understanding of genetic
function and regulation in the field of plant pathology. Currently in use is
a custom Arabidopsis thaliana whole genome array that contains 26412
probe
sets representing 26367 Arabidopsis genes.
Previously (before 2002), another custom chip was used that contained ~ 8600
probe sets. This chip contained roughly 32 probes per gene and covered around
1/3rd of the genome.
Analysis of gene activity patters is performed with multiple graphics display
programs such as those found in the Michael
Eisen's Software package (Cluster and TreeView) and in Silicon
Genetics' GeneSpring. Cluster and TreeView provides a quick, yet distinctive
method for the generation of well-defined gene clusters based on common expression
characteristics. GeneSpring is a more comprehensive tool used for displaying
anything from expression profiling to physical positioning and statistical selection.
Current examples of such analysis can be seen in other lab publications.
Some of the ultimate goals are to discover genes that are activated specifically
in response to certain defense treatments and to assign these to defined pathways
of the plant immune system. In addition, we categorize genes based on their
responses to a variety of different defense-related treatments. In promoters
of strictly co-regulated genes we identified (with the help of AlignACE
and BioProspector)
highly conserved sequence motifs, which may be binding sites of transcription
factors responsible for their co-regulation
Funded by:
Collaborations with:
