Isolation and characterization of a Fusarium oxysporum-resistant gene LrGLP1 from Lilium regale Wilson

Abstract

Germin-like proteins (GLPs) play important roles in plant defense responses. A GLP gene was isolated from Lilium regale Wilson and designated as LrGLP1. The LrGLP1 gene was induced by exogenous ethylene and the incompatible interaction between L. regale and Fusarium oxysporum f. sp. lilii. To verify the biological function of LrGLP1, an overexpression vector of LrGLP1 was constructed and transferred into Nicotiana tabacum L. cv Xanthi. Quantitative reverse transcription-PCR (qRT-PCR) analysis demonstrated that LrGLP1 was expressed in the T1 transgenic tobacco lines, and MnSOD, Cu/ZnSOD, as well as PR1 were induced by the overexpression of LrGLP1. Moreover, the LrGLP1 transgenic tobacco lines showed much stronger resistance to F. oxysporum infection than did the wild type (WT). In addition, both the SOD and OXO activities in all the LrGLP1 transgenic tobacco lines were significantly higher than those in WT plants during F. oxysporum infection, and overexpression of LrGLP1 enhanced the reactive oxygen species (ROS)-scavenging ability of transgenic tobacco lines. Based on these results, LrGLP1 is an important defense gene involved in response to F. oxysporum in L. regale Wilson.