Function of VtPGIP in pathogenic fungus resistance of Vitis thunbergii

In plants, polygalacturonase inhibitor proteins (PGIPs) are very important to inactivate polygalacturonases secreted by pathogens. Vitis thunbergii Sieb. et Zucc. polygalacturonase inhibitor proteins (VtPGIP) was first isolated from the wild grape Vitis thunbergii Sieb. et Zucc., which exhibits high resistance to disease. VtPGIP is sublocated in the plant cell wall, and this location is consistent with the function of PGIPs in the first line of host defense. The promoter of VtPGIP contains salicylic acid (SA), abscisic acid (ABA), and fungus infection response elements. Results from real-time quantitative reverse transcriptase (RT)-PCR analysis showed that VtPGIP expression was induced by SA, ABA, and fungi. The results indicated that VtPGIP may have important functions in defense-related responses of V. thunbergii against pathogenic fungi.