Expression profiling of transcription factors (TFs) in sugarcane X Colletotrichum falcatum interaction

Sugarcane is one of the most important commercial crops in India, supporting the second largest agro-based sugar industry. However for more than a century, the production is imperiled by the most devastating fungus Colletotrichum falcatum Went, which causes red rot in sugarcane. Complex polyploidy and limited understanding on the inheritance to red rot resistance makes breeding efforts more complicated in sugarcane. Transcription factors (TFs) play a key role in regulating defense response, which offers much promise for the manipulation of metabolic pathways, potential in regulating multiple signaling networks leading to plant defense against pathogens. In order to better manage red rot disease in sugarcane, we sought to screen the TFs possibly involving in pathogen defense by analyzing 5 major defense-related TF classes (WRKY, bZIP, MYB, NAC and TLP). In this study two parallel sets of experiments were carried out to compare the differential regulation of these classes of TFs upon pathogen challenge and SAR priming. Among the 41 TFs studied, differential regulation of 24 TFs upon pathogen challenge and 15 TFs upon SAR inducer priming were observed. Comparison of incompatible interaction and SAR inducer priming revealed that 8 TFs were highly induced in both the cases. Collectively, the results showed that TFs which are significantly induced early may involve actively in triggering or co-ordinating defense against pathogen invasion.