Function and significance of the biological clocks in polar planktonic organisms are the focus of the virtual Helmholtz Institute entitled PolarTime starting July 1st, 2012. It is one of eleven new virtual institutes funded by Germany's Helmholtz Association. PolarTime, coordinated by the Alfred Wegener Institute for Polar and Marine Research, will be supported for up to five years with approximately three million euros from the impulse and network fund of the Helmholtz Association.
The anthropogenic influence on the climate system is particularly pronounced in Polar Regions. Examples of environmental changes in the Arctic and Antarctic include the receding of sea ice and ocean warming. How do marine organisms react to these changes in the environment given that their vital processes, such as reproduction cycles and seasonable food availability, have been synchronised with the environment over millions of years? To be able to answer these questions, researchers in the virtual Helmholtz Institute PolarTime are taking a very close look at Antarctic krill (scientific name: Euphausia superba). It serves as a model organism for a polar plankton species which has adapted to the extreme conditions.
Krill plays a key role in the foodwebs of the South Ocean. During the course of evolution krill has developed a large number of biological rhythms that are closely connected to large seasonal changes in its environment. Almost all organisms, from protozoan to humans have adapted to the periodic change from day to night by developing an inner biological clock. This clock permits the synchronisation of physiological and behavioural processes with the diurnal variability in environmental conditions. It can also determine the seasonal rhythms with surprising temporal precision. However, the inner clock must be reset from time to time. This happens thanks to so-called outer "timers" such as the length of daylight (photoperiod).
A team around spokesmen Dr. Bettina Meyer from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association and Dr. Mathias Teschke from the Charit University Medicine Berlin will, in future, investigate the principles, interactions and evolution of endogenous biological rhythms and clocks in pelagic organisms of the Polar Regions using Antarctic krill as a model organism. Cooperation partners are the Carl von Ossietzky University of Oldenburg, the Helmholtz Centre for Environmental Research (UFZ) in Leipzig as well as the Italian University of Padua and the Australian Antarctic Institute in Hobart (Tasmania).
Research at the Alfred Wegener Institute will focus on physiology. "We are currently investigating, for example, the conditions under which genes and enzymes are active and how these are controlled by the inner clock", says Meyer. Her colleague, Mathias Teschke, has already started investigating krill's inner clock during a research project funded by the German Research Foundation. "The studies on krill will provide a solid basis to investigate the inner clock and its mode of action of other key polar marine organisms which assume a central function in polar ecosystems", explains Teschke.
Scientists of two working groups from the University of Oldenburg will use the knowledge gained on individual organisms to determine the population dynamics of key species and the response of population shifts on the Antarctic ecosystem. Evolutionary biologists around Prof. Dr. Gabriele Gerlach will investigate whether the krill populations in the East and West Antarctic sectors differ from each other, as climate fluctuations are considerably larger in the Western than in the Eastern sector. The working group of Prof. Dr. Bernd Blasius uses the physiological data to develop mathematical models in order to test the impact of different climate change scenarios on the inner clock and the associated vital functions of marine organisms.
"With the establishment of joint professorship for 'Biological Processes and Biodiversity in Polar Regions' we would like to ascertain a long-term cooperation with the University of Oldenburg", says Prof. Dr. Karin Lochte, Director of the Alfred Wegener Institute. Furthermore, a joint working group "Marine Chronobiology" is to be set up in which Teschke can contribute his expertise from the Berlin Charit. "In order to introduce the innovative research area of PolarTime into teaching theory, a 'Chronobiology in Marine Environments' summer school will be set up at the University of Oldenburg", reports Prof. Dr. Babette Simon, President of the Carl von Ossietzky University. An exchange programme for master's and PhD students is also planned with the international cooperation partners as well as a circuit lecture on different areas of chronobiology.
The virtual Helmholtz Institute PolarTime - Biological timing in a changing marine environment: Clocks and rhythms in polar pelagic organisms
Coordination: Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association; spokes persons: PD Dr. Bettina Meyer, Dr. Mathias Teschke
Carl von Ossietzky University of Oldenburg, Prof. Dr. Gabriele Gerlach, Prof. Dr. Bernd Blasius
Charit University Medicine Berlin: Prof. Dr. Achim Kramer, Dr. Mathias Teschke
Helmholtz Centre for Environmental Research (UFZ) in Leipzig: Prof. Dr. Volker Grimm, Dr. Karin Johst
Australian Antarctic Division: Dr. So Kawaguchi, Dr. Simon Jarman
University of Padua: Prof. Dr. Rudolfo Costa
|Contact: Dr. Folke Mehrtens|
Helmholtz Association of German Research Centres