Expression Analysis of Chitinase Upon Challenge Inoculation to Wounding and Defense Inducers in

Chitinases are the hydrolytic enzymes which belong to the pathogenesis-related (PR) protein family and play an important role not only in plant defense but also in various abiotic stresses. However, only a limited number of chitinase genes have been characterised in . In this study, we have characterised class IV chitinase gene (accession no EF586206) in response to fungal infection, salicylic acid (SA), jasmonic acid (JA) treatments and wounding. Gene expression studies revealed that the transcript levels of () gene increases significantly both in local and distal tissues after infection. gene was also induced by jasmonic acid and wounding but moderately by salicylic acid. A 2.5 kb class IV chitinase promoter of this gene was isolated from by Genome walking (accession no KF055403.1). analysis of this promoter revealed a number of conserved -regulatory elements related to defense, wounding and signalling molecules like SA, and JA. For validation, chitinase promoter was fused to the GUS gene, and the resultant construct was then introduced into plants. Histochemical analysis of T transgenic Arabidopsis plants showed that higher GUS activity in leaves after fungal infection, wounding and JA treatment but weakly by SA. GUS activity was seen in meristematic tissues, young leaves, seeds and siliques. Finally investigation has led to the identification of a pathogen-inducible, developmentally regulated and organ-specific promoter. Present study revealed that () promoter is induced during biotic and environmental stress and it can be used in developing finely tuned transgenics.