Light-Activated Phytochrome A and B Interact with Members of the SPA Family to Promote Photomorphogenesis in Arabidopsis by Reorganizing the COP1/SPA Complex

Author Profile

David J. Sheerin, Chiara Menon, and Sven zur Oven-Krockhaus

David J. Sheerin

Current Position: Researcher, Department of Botany at the University of Freiburg, Germany.

Education: PhD: Institute for Molecular Biosciences, Massey University, New Zealand.

Non-scientific Interests: Reading, hiking, and mountain climbing.

I specialized in plant sciences during my post-graduate studies in the lab of Dr. Jasna Rakonjac, performed in collaboration with Plant and Food Research New Zealand. My doctoral research focused on the functions of the DELLA proteins in gibberellin signaling, which is important in controlling yields of many crop species. The discovery by both de Lucas et. al. and Feng et. al. of the involvement of the phytochrome interacting factors (PIFs) in cross-signaling between light and gibberellin pathways to regulate hypocotyl elongation introduced me to the field of plant light perception. This lead to me moving to Germany to start a post-doctoral position with Dr. Andreas Hiltbrunner to study phytochrome A signaling. In screening for new components, we isolated SPA1 and several other new interactors. There was strong biological evidence that phyA regulates the activity of the SPA1-COP1 complex, leading us to investigate how a phyA-SPA1 interaction may contribute. It was interesting to find striking similarities to the effects of blue-light perceptive cryptochromes on the SPA1-COP1 complex, revealing a point of convergent signaling.

Chiara Menon

Current Position: PhD student at the Department of Botany, University of Freiburg, Germany, in cooperation with the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Germany.

Education: M.S (2011) in Biology at the Center for Plant Molecular Biology (ZMBP), University of Tübingen, Germany and B.S (2005) in Biology at University of Ferrara, Italy.

Non-scientific Interests: Swimming, traveling and enjoying the free time with my son, husband and friends.

After my bachelor in biology at the University of Ferrara in Italy I decided to obtain my master's degree at the ZMBP of the University of Tübingen in order to increase my education in plant molecular biology and to acquire international experience. By joining the research group of Prof. Hiltbrunner at the University of Freiburg as a PhD student, I started to work on the fascinating field of photobiology, in particular on the molecular mechanism for phytochrome A-mediated light perception transduction and modulation of light responses. One of the most interesting research projects of my work was the investigation of the influence and function of phytochrome A on COP1/SPA protein interactions as described. Doing research within the field of phytochrome signaling is challenging and at the same time exciting - I am looking forward to continue investigating many other open questions.

Sven zur Oven-Krockhaus

Current Position: Research assistant at The Institute for Physical and Theoretical Chemistry / The Center for Plant Molecular Biology (ZMBP), University of Tübingen.

Education: Diploma degree in chemistry (Diploma thesis title "Photophysical characterization of multicolor bimolecular fluorescence complementation"), PhD student in the field of physical chemistry since 2011.

Non-scientific Interests: Volleyball and sports in general, cooking, watching movies and listening to music (especially trip-hop and indie-pop singer-songwriter).

As a kid I often hung around in our local library - mainly to read comic books. At some point I browsed around and got hold of a chemistry book. I was fascinated by the idea of our world being composed of smallest particles and their interactions. This early interest not only set my direction in school, where I strongly leant towards natural sciences, but also brought me to study chemistry. At the university I soon got curious about life sciences and combined this new interest by specializing in physical chemistry and biochemistry in the last year of my chemistry studies. I was then lucky enough to join the group of Dr. Frank Schleifenbaum, whose research is situated between physical chemistry and plant physiology. This was exactly the niche I was looking for - using the background and tools of physical chemistry to reveal and explain processes in living organisms. In a practical course and my Diploma thesis I mainly focused on spectroscopy, live cell imaging and fluorescent lifetime imaging microscopy (FLIM) to investigate protein-protein interactions. This lead to my subsequent PhD thesis on the subject of "Functional analysis of nuclear bodies in plants by local-optical spectro-microscopy". For a closer look at pivotal structures in plant cells, I am currently in the process of building up a super-resolution microscope with PALM/STORM capabilities.