Expression of signalling and defence‐related genes mediated by over‐expression of <i> <scp>JERF</scp> 1 </i> , and increased resistance to sheath blight in rice

Abstract

Sheath blight ( SB ) is one of the most destructive rice diseases that affect the yield and quality of rice. J asmonate and E thylene R esponse F actor 1 , designated JERF 1 , can be induced by ethylene, methyl jasmonate ( M e JA ), abscisic acid (ABA) and salt stress. Previous research demonstrated that over‐expression of JERF 1 enhanced drought tolerance by regulating the expression of stress‐related genes in rice. The present study reports that JERF 1 could improve SB resistance of transgenic rice. At the molecular and physiological levels, JERF 1 could up‐regulate the expression of signalling and defence‐related genes and increase the activities of lipoxygenase ( LOX ) and phenylalanine ammonia lyase ( PAL ). Analysis of cis ‐elements showed that there were several DRE / CRT (dehydration‐responsive element/ C ‐repeat) and/or GCC boxes in the promoters of these candidate genes, indicating that JERF 1 might regulate the expression of defence‐related genes via interaction with these cis ‐elements. These results suggest that JERF 1 might improve SB resistance by modulating the expression of defence‐related genes. This may prove to be a useful strategy for genetic engineering to improve SB resistance using transcription factor genes in rice.