prof.dr. MGM (Mark) Aarts

The research interests of my group concern the evolution of plant adaptation to the abiotic environment. For much of this work we use Arabidopsis thaliana, the long-term plant model species.

We investigate the natural variation for abiotic stress tolerance and response of Arabidopsis with molecular and quantitative genetic tools such as CRISPR-Cas9 or RNAi, through stable and transient transformations, or through QTL and genome-wide association analysis, making use of genetically segregating populations created in the lab or obtained from international collaborators or stock centres. I am especially interested in two topics, understanding the (variation for) regulation of zinc homeostasis in plants and identification of the natural variation underlying efficiency of photosynthesis under the influence of environment.

An extreme case of aberrant regulation of zinc homeostasis is found in Noccaea caerulescens (see picture), a Zn/Cd/Ni hyperaccumulating relative of Arabidopsis, for which we determined the whole genome sequence. Evolution of  metal hyperaccumulation in N. caerulescens is studied using population genomics and quantitative genetics, supplemented with mutant screens and gene function analysis molecular genetics. Current focus is on the role of copy number variation in the rapid adaptation to high Zn and/or Cd exposure.

For our photosynthesis research we perform genome wide association studies in Arabidopsis, but also examine the nuclear-cytoplasmic interaction in so-called cytoplasmic swap panels, in which novel nuclear-cytoplasmic combinations are represented. Allelic variation is as much as possible unraveled up to the mutations causal for the observed phenotypic variation.

Another species we examine is Hirschfeldia incana, Mediterranean mustard, which displays exceptionally high levels of photosynthesis at high light, especially for a C3 photosynthesis plant.