Prokaryotic to plant phytochrome function
Principal Investigators: Prof. Dr. Jon Hughes (JLU)
In Project B8, we are studying the mechanism of phytochrome phototransformation between the Pr and Pfr states. We focus on plant phytochromes because of their huge importance both agriculturally and ecologically: phytochromes control the largest environmentally-regulated developmental changes known in nature (germination, de-etiolation, shade avoidance, flowering time and many other processes), regulating the expression of thousands of genes. We are extending our work on prokaryotic phytochromes to plant phytochromes to help understand their unique physiological functions. In particular, we want to understand the connection between chromophore photoisomerization, protonation dynamics and subsequent domain movements in the photoconversion process. Since joining the SFB in 01.2017, we have successfully crystallized and solved the 3D structures of four different plant phytochrome constructs in the Pr state, UV-vis (absorbance and CD) as well as vibrational (Raman and IR difference) spectroscopy providing extensive further information regarding the chromophore geometry, hydrogen bond networks and protonation dynamics in both the Pr and the physiologically-active Pfr states.
Publications 2017 - 2020
Nagano, S., Guan, K., Shenkutie, S., Feiler, C., Weiss, M. S., Kraskov, A., Buhrke, D., Hildebrandt, P., Hughes, J. (2020). Structural insights into photoactivation and signalling in plant phytochromes. Nature Plants 6, 581-588.
Sadeghi, M., Balke, J., Schneider, C., Nagano, S., Stellmacher, J., Lochnit, G., Lang, C., Weise, C., Hughes, J., and Alexiev, U. (2020). Transient deprotonation of the chromophore affects protein dynamics proximal and distal to the linear tetrapyrrole chromophore in phytochrome Cph1. Biochemistry 59,1051-1062. doi: 10.1021/acs.biochem.9b00967.
Song, C., Mroginski, M.A., Lang, C., Kopycki, J., Gartner, W., Matysik, J., and Hughes, J. (2018). 3D Structures of Plant Phytochrome A as Pr and Pfr From Solid-State NMR: Implications for Molecular Function. Frontiers in Plant Science 9, 498.
Stensitzki, T., Yang, Y., Wölke, A.L., Knapp, E.-W., Hughes, J., Mroginski, M.A., and Heyne, K. (2017). Influence of Heterogeneity on the Ultrafast Photoisomerization Dynamics of Pfr in Cph1 Phytochrome. Photochemistry and Photobiology 93, 703-712.
Velazquez Escobar, F., Kneip, C., Michael, N., Hildebrandt, T., Tavraz, N., Gärtner, W., Hughes, J., Friedrich, T., Scheerer, P., Mroginski, M.A., and Hildebrandt, P. (2020). The Lumi-R Intermediates of Prototypical Phytochromes. Journal of Physical Chemistry B 124, 4044-4055. doi: 10.1021/acs.jpcb.0c01059.