Arabidopsis peroxidase AtPRX53 influences cell elongation and susceptibility to heterodera schachtii

Abstract

Cyst nematodes establish and maintain feeding sites (syncytia) in the roots of host plants by altering expression of host genes. Among these genes are members of the large gene family of class III peroxidases, which have reported functions in a variety of biological processes. In this study, we used Arabidopsis-Heterodera schachtii as a model system to functionally characterize peroxidase 53 (AtPRX53). Promoter assays showed that under non-infected conditions AtPRX53 is expressed mainly in the root, the hypocotyl and the base of the pistil. Under infected conditions, the AtPRX53 promoter showed up regulation at the nematode penetration sites and in their migration paths. Interestingly, strong GUS activity was observed in H. schachtii-induced syncytia during the early stage of infection and remained strong in the syncytia of third-stage juveniles. Also, AtPRX53 showed up regulation in response to wounding a nd jasmonic acid treatments. Manipulation of AtPRX53 expression through over expression and knockout mutation affected both plant morphology and nematode susceptibility. While AtPRX53 over expression lines exhibited short hypocotyls, aberrant flower development and reduced nematode susceptibility to H. schachtii, the atprx53 mutant showed long hypocotyls and a 3-carpel silique phenotype as well as a non-significant increase of nematode susceptibility. Taken together these data, therefore, indicate diverse roles of AtPRX53 in the wound response, flower development and syncytium formation. © 2011 Landes Bioscience.