BASAL GENE TRANSCRIPTION CONTRIBUTES TO DISEASE TOLERANCE IN Lotus japonicus ECOTYPE GIFU

BORDENAVE CD ; BABUIN MF; ESCARAY FJ ; CAMPESTRE MP; ROCCO RA; ANTONELLI C ; SERNA E ; RUIZ OA

Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

We previously reported the analysis of the transcriptional reprogramming that occurs in  Lotus japonicus during the pathogenic interaction with  Pseudomonas syringae. That  study included the ecotypes MG20 and Gifu showing susceptible and tolerant phenotypes, respectively, and allowed us to evaluate candidate genes with a probable role in the establishment of an effective defense response. In an attempt to identify new genes involved, in the present work we studied the differences in gene expression that exist in both ecotypes in non-treated (control) conditions. In this case, our analysis shows 2874 differentially expressed genes, 60% of them showing greater expression in the ecotype Gifu. At least 691 genes are predicted to have a role during biotic stress and might contribute to tolerance. Most of them participate in general protein metabolism as well as synthesis of flavonoids and jasmonic acid, two compounds with an important role in plant defense. Interestingly, many of the genes that show a higher expression in the ecotype Gifu are consequently induced in the susceptible MG20 under bacterial infection.  These observations suggest that basal gene expression in the ecotype Gifu might explain, at least partially, the higher tolerance to pathogen attack. The importance of these genes during plant defense and the similarities with previously published reports are discussed.