ZmGLP1 , a Germin-like Protein from Maize, Plays an Important Role in the Regulation of Pathogen Resistance.

A gene encoding a protein similar to germin-like proteins (GLPs) was obtained from maize () and designated as . Based on the conserved domain and phylogenetic status, was grouped into GLP subfamily b and has high similarity to from . is expressed in different maize tissues during different growth stages and is mainly expressed in the stems and leaves. The induced expression patterns confirmed that is differentially expressed under abiotic and hormone stress; it had an early response to jasmonic acid (JA) and ethephon (ET) but a late response to salicylic acid (SA) and was significantly upregulated under infection. The overexpression of in improved the resistance to biotrophic pv. tomato DC3000 (DC3000) and necrotrophic by inducing the expression of JA signaling-related genes. Moreover, the hydrogen peroxide (HO) content increased due to the overexpression of in after pathogen infection. Compared to the wild-type control, the HO content of -overexpressing infected by increased significantly but was lower in transgenic plants infected with . Furthermore, high-performance liquid chromatography-tandem mass (HPLC-MS/MS) spectrometry showed that the JA contents of -overexpressing markedly increased after pathogen infection. However, the improved resistance of -overexpressing pretreated with the JA biosynthetic inhibitor, sodium diethyldithiocarbamate trihydrate (DIECA), was suppressed. Based on these findings, we speculate that plays an important role in the regulation of resistance to biotrophic DC3000 and necrotrophic ; the regulatory effects are achieved by inducing plant oxidative burst activity and activation of the JA signaling pathway.