The pathogen-inducible promoter of defense-related LsGRP1 gene from Lilium functioning in phylogenetically distinct species of plants.

A suitable promoter greatly enhances the efficiency of target gene expression of plant molecular breeding and farming; however, only very few promoters are available for economically important non-graminaceous ornamental monocots. In this study, an 868-bp upstream region of defense-related LsGRP1 of Lilium, named PLsGRP1, was cloned by genome walking and proven to exhibit promoter activity in Nicotiana benthamiana and Lilium 'Stargazer' as assayed by agroinfiltration-based β-glucuronidase (GUS) expression system. Many putative biotic stress-, abiotic stress- and physiological regulation-related cis-acting elements were found in PLsGRP1. Serial deletion analysis of PLsGRP1 performed in Nicotiana tabacum var. Wisconsin 38 accompanied with types of treatments indicated that 868-bp PLsGRP1 was highly induced upon pathogen challenges and cold stress while the 131-bp 3'-end region of PLsGRP1 could be dramatically induced by many kinds of abiotic stresses, biotic stresses and phytohormone treatments. Besides, transient GUS expression in a fern, gymnosperms, monocots and dicots revealed good promotor activity of PLsGRP1 in many phylogenetically distinct plant species. Thus, pathogen-inducible PLsGRP1 and its 131-bp 3'-end region are presumed potential as tools for plant molecular breeding and farming.