Identification of transcription factors in tomato, potentially related to early blight resistance at invasion in host tissue, using microarray expression profiling

• This study is an attempt to understand the regulatory network of transcription factors which play role in resistance response in tomato under stress of early blight pathogen (A. solani).
• At the very initial stage, i.e. penetration of host tissue by fungal mycelium (24 hai), the samples were collected and transcriptome profiling was done using Affymetrix Gene Chip and it has shown differential expression of different transcription factors. Also these have been compared with previous studies and found that these TFs are important in regulatory network of resistance pathways.

Tomato early blight is an important threat due to its capacity to reduce the production in all major tomato producing areas. Molecular mechanisms underlying resistance to the causal organism are not well known. Therefore, we aimed to study tomato – Alternaria solani system to search the transcription factors and pathways which, are responsible for resistance to this fungi using, affymetrix gene chip for tomato. three hundred ninety five transcription factors were found to be differentially expressed at 24 h after inoculation with A. solani in the resistant genotype, EC-520,061, of tomato. Also, Zinc Finger Proteins, Ribosomal binding unit S4 and Auxin responsive transcription factors were found to play significant role in resistance. Their expression has enhanced the pathogenesis related proteins and also other proteins as well, which, have direct role in stopping the penetration of mycelia in host plant.