Dissection of the epoxyjanthitrem pathway in Epichloë sp. LpTG-3 strain AR37 by CRISPR gene editing

Epichloë festucae var. lolii and sp. Lp TG-3 are filamentous fungal endophytes of perennial ryegrass ( Lolium perenne ) that have a substantial impact on New Zealand’s agricultural economy by conferring biotic advantages to the host grass. Overall, contribute NZ$200 million annually, with strain AR37 estimated NZ$3.6 billion Zealand over 20-year period. This produces secondary metabolites, including epoxyjanthitrems, which class indole diterpenes, associated observed effects livestock insect pests. Until very recently, was intractable genetic modification but this has changed application CRISPR-Cas9 based gene editing techniques. In paper, inactivation used deconvolute basis for epoxyjanthitrem biosynthesis, creating an been edited remove biosynthesis all diterpenes. We show can be achieved without off-target events or introduction foreign DNA (footprint-less) through AMA1-based plasmid simultaneously expresses system selectable marker. Genetic in these transformants were investigated genome sequencing planta chemistry.