A multidisciplinary approach to dissect the molecular basis of the Neotyphodium lolii/ryegrass symbiosis

Neotyphodium lolii is a fungal endophyte that lives entirely within the intercellular spaces of its grass host, perennial ryegrass (Lolium perenne L.). Infection is symptomless and the endophyte relies on the host plant for dissemination via the seed. The association is mutually beneficial since the endophyte confers a number of biotic and abiotic advantages to the host. This paper will present an overview of the multidisciplinary approach we are using at AgResearch to dissect the molecular basis of this symbiosis. Topics covered will include how we intend to link the knowledge gained from basic biology and cytology with the fields of Genomics, Transcriptomics, Proteomics and Metabolomics. To achieve this we are using isogenic ryegrass lines infected or uninfected with endophyte in combination with a suite of molecular biology tools, including Expressed Sequence Tags (ESTs), Microarray analysis, 2D-gel electrophoresis (to identify novel proteins associated with symbiosis), and metabolic profiling. To aid our proteomics approach, we have also generated both fungal genomic and fungal EST resources. By linking these approaches we hope to identify genes which are important in both the establishment and maintenance of symbiosis. In addition, by combining transcriptomic with metabolomic approaches, we intend to elucidate how endophyte infection influences host secondary metabolism. We hypothesise the latter is correlated with many of the endophyte-conferred enhancements to its host