Melis Akman
I have completed my master degree in Middle East Technical University, Ankara. I studied phylogenetics of a relic endemic tree species of Turkey, Turkish sweetgum (Liquidambar orientalis). After completing my master degree, I have started my PhD within Experimental Plant Systematics Group.
My research
The frequency of major floods has increased significantly in the last century and this trend is expected to continue due to climate change. These floods can destroy both crop and natural plant populations, thus it is important to understand the mechanisms involved in submergence stress. For this purpose, we have studied two different systems, Arabidopsis (as a model system) and Rorippa (as an ecologically relevant system) to understand the genetic basis of submergence tolerance. We investigated the Kas-1/Col-gl1 recombinant inbred line population of Arabidopsis thaliana. We recorded survival after submergence (3-13 days) and used LT50 values in for QTL analysis. We found a single QTL in two independent experiments. In the QTL region, there are several candidate anoxia-related genes . We are currently fine-mapping the QTL to identify the causal gene. We showed that two wetland species of Brassicaceae family, Rorippa amphibia and Rorippa sylvestris have low levels of mortality even after 3 months of flooding. Of these two species, R. sylvestris achieves a higher survival by adopting a quiescence strategy (with low carbohydrate consumption), contrasting to the escape strategy by stem elongation of R. amphibia (with high carbohydrate consumption). In rice, the ethylene response factor (ERF) genes control the quiescence vs escape stragies. Hence, we cloned Rorippa ERF homologs. Conserved regions of one of the Rorippa ERF genes cluster with the well-known rice ERF genes (SUB1 and, SNORKEL), with HRE1 being the closest ortholog from A. thaliana. The role of Rorippa ERFs are being investigated with expression analysis and transformation into Arabidopsis.