Fig. 2

Transcriptome analyses support host-induced phenotypic diversification. a Eight cDNA samples from Petri plate cultures were clustered based on their global expression patterns of 14,339 transcripts. Group A consists of the two California bay isolates used as inocula and re-isolates from canyon live oak, all having wt colony phenotype. Isolates in group B are either from naturally infected coast live oak or from artificially-inoculated canyon live oak, and all have nwt colony phenotype. b Examples of mRNA profiles of P. ramorum genes differentially expressed between group A and group B. The order of isolates is same as that in a. A gene model number and its annotation are shown for each profile. Gene expression of PR_72359 and PR_49580 were estimated by qRT-PCR, and log2 fold changes (−ΔΔCT) are shown. PR_76099 was used as endogenous control gene, and expression levels were standardized to the genome sequence strain Pr-102. For PR_49580, because the reference PR-102 had a high expression level, its expression was offset by 12 for the presentation purpose. Error bars represent SD in technical replicates. For PR_87381 and PR_78074, bars represent estimates of the relative expression levels according to microarray mRNA profiling