Cloning and gene expressions of stress responsive gene HbPRX53 in rubber tree

Peroxidase activity significantly increased under drought stress in rubber tree. To identify the functions of peroxidase genes responsive to drought stress，the full-length cDNA of HbPRX53 was isolated from rubber tree. Bioinformatics analysis showed that HbPRX53 contained 334 amino acid residues and a plant peroxidase-like superfamily domain. Phylogenetic analysis with Arabidopsis Class III peroxidases revealed that HbPRX53 shared high identities with AtPRX53. Although HbPRX53 was expressed in bark，leaf，latex and flower，it was preferentially expressed in leaf in rubber tree. HbPRX53 expression was significantly upregulated in leaves by powdery mildew infection，mechanical wounding and drought stress. Moreover，indole acetic acid， abscisic acid，salicylic acid ethylene，H2O2 and methyl jasmonate treatments also led to marked accumulation of HbPRX53 transcripts in leaves. These results indicated HbPRX53 is a key factor in both biotic and abiotic stress responses in rubber tree.