Applicants

Professor Dr. Peter Kroth

Universität Konstanz
Mathematisch-Naturwissenschaftliche Sektion
Fachbereich Biologie
Arbeitsgruppe Ökophysiologie der Pflanzen

Dr. Sylke Wohlrab

Alfred-Wegener-Institut
Helmholtz-Zentrum für Polar- und Meeresforschung

Project description

Latitudinal diurnal and annual light regimes are one of the most stable environmental signals and, together with local climatic conditions and biochemical water properties, they determine the spectral light composition and light intensity in the ocean. Marine organisms have adapted to these local light conditions, which in turn increases their fitness and contributes to the persistence of the respective species. In marine microeukaryotes, a variety of photoreceptors are known to be involved in this process of adaptation to the prevailing light regime. However, there are no studies on specific adaptations of photoreceptors in polar marine microeukaryotes, although the polar light field is particular due to its extreme seasonality, including long periods of darkness and long periods of low solar elevation angle. Our goal is therefore to understand how photoreceptors, particularly primary producers, in the Southern Ocean, which form the basis of critically important ecosystem processes, are involved in their adaptations to local light conditions. The goal of this project contributes to 3 overarching themes: 1) Response to Environmental Change, 2) Linkages with Lower Latitudes, and 3) Improved Understanding of Polar Processes and Mechanisms. To achieve the project goal, we will undertake different types of investigations, the results of which will provide scientifically coherent information. This includes a comparative analysis of blue light photoreceptors, based on newly generated sequence data as well as publicly available genome, transcriptome, and metatranscriptome data. This approach will allow us to identify biogeographic boundaries of specific blue light photoreceptor sequences. In addition, we will use the sequence information for a protein-level biophysical characterization of blue light photoreceptors. Based on intracellular signals elicited by blue light photoreceptors and the biophysical characterization at the protein level, we will obtain an assessment of their sensitivity to the spectral composition of the blue light field. Overall, the results of this project will provide insight into how unique the receptors in the Southern Ocean are in terms of sequence evolution, sensitivity, and adsorption behavior. With respect to ongoing global changes, this can inform us on how specific adaptations to local photic environments can limit range shifts, as temperatures in polar regions are undoubtedly rising but solar elevation is not.

DFG Programme: Infrastructure Priority Programmes

term since 2023