Datum en tijd 25-10-2019, 20:00 - 21:15
Prof. dr. P.M. Bleeker
Plant Physiologie, Fac. Natuurwetenschappen, Wiskunde en Informatica,UVA
Swammerdam Institue for Life Sciences ( voorafgegaan door ALV )
[ Tijdelijke inleiding, gecopieerd van UVA – Swammerdam Institute for Life Sciences]
Natural variation in specialised metabolites against pest
We focus on defence against pests via the production of specialised compounds in tomato glandular hairs (trichomes). The general aim of my research is to explore natural variation in wild tomato trichomes, to identify metabolites, genes and regulatory elements needed to reconstruct natural and sustainable defence pathways in cultivated tomato. I work in close collaboration with the biotech and breeding industry, facilitating the translation of our work to the practice of tomato breeding.
Explore natural variation in wild tomatoes
Wild tomato species have the ability to defend themselves by producing a wide variety of natural defence compounds that have a toxic, antifeedant or repellent effect on insects. These metabolites encompass a variation of chemical families, e.g. terpenoids, flavonoids, acylsugars and alkaloids. In tomato, such specialised compounds are mostly produced and stored in trichomes, on the surface of leaves and stems. They do so either constitutively or upon pest attack. Extensive tomato breeding focussed mostly on yield, pathogen resistance and fruit characteristics. Protection against insects, and other pests, was accomplished largely by growing in closed (greenhouse) environments or the application of chemical pesticides. This breeding process has led to a loss of ability to produce effective defence compounds in cultivated tomato species. The rationale behind targeting these trichomes, that are absent on tomato edible parts, is to be able to bring back ‘wild defence mechanisms’ without compromising the commercial product. Because trichomes are accessible structures, they provide an excellent model system to study this.
Role of sRNAs
Many biosynthetic genes involved in specialized metabolite production have been discovered. Also, various transcription factors have been identified that play a role in the regulation of the metabolic flux. More recently it was shown that endogenous small RNAs (sRNAs) can be crucial regulators of gene expression in plants.
We investigate regulation of metabolite production and aim to identify small RNAs and their targets and assess their role as regulatory elements involved in the production of defense compounds produced in trichomes of pest-resistant tomatoes.