Prof. Andreas Hiltbrunner

Light Perception and Signalling in Plants

Phytochromes are red/far-red photoreceptors in plants, which are important to adapt growth and development to the environment. They localise to the cytosol in the dark and translocate into the nucleus in plants exposed to light. Phytochrome interacting factors (PIFs), COP1 and SPA proteins act downstream of phytochromes and actively suppress photomorphogenic development. After transport into the nucleus, light activated phytochromes target PIFs for degradation and inactivate the COP1/SPA complex to promote photomorphogenesis. Understanding how phytochrome nuclear transport is regulated, how it is linked to downstream signalling and how downstream signalling results in regulation of gene expression are major topics in our research.

Phytochromes are ubiquitous in the plant kingdom and also present in green algae, mosses and ferns, i.e. in cryptogams. Both in seed plants and cryptogams the phytochrome families consist of several members, which have overlapping but also specific functions. Using Arabidopsis thaliana and Physcomitrella patens as model systems for seed plants and cryptogams, we also investigate how species-specific light signalling pathways evolved.

10 selected publications:

• The phytochrome interacting proteins ERF55 and ERF58 repress light-induced seed germination in Arabidopsis thaliana.
  Li Z, Sheerin DJ, von Roepenack-Lahaye E, Stahl M, Hiltbrunner A (2022).
  Nat Commun. 13(1):1656.
• Uncovering a novel function of the CCR4-NOT complex in phytochrome A-mediated light signalling in plants.
  Schwenk P, Sheerin DJ, Ponnu J, Staudt AM, Lesch KL, Lichtenberg E, Medzihradszky KF, Hoecker U, Klement E, Viczián A, Hiltbrunner A (2021).
  Elife. 10:e63697
• COLD REGULATED 27 and 28 are targets of CONSTITUTIVELY PHOTOMORPHOGENIC 1 and negatively affect phytochrome B signalling.
  Kahle N, Sheerin DJ, Fischbach P, Koch LA, Schwenk P, Lambert D, Rodriguez R, Kerner K, Hoecker U, Zurbriggen MD, Hiltbrunner A (2020).
  Plant J. 104(4):1038-1053.
• PCH1 and PCHL promote photomorphogenesis in plants by controlling phytochrome B dark reversion.
  Enderle B, Sheerin DJ, Paik I, Kathare PK, Schwenk P, Klose C, Ulbrich MH, Huq E, Hiltbrunner A (2017).
  Nat Commun 8:2221.
• Characterization of phytochrome interacting factors from the moss Physcomitrella patens illustrates conservation of phytochrome signaling modules in land plants.
  Possart A*#, Xu T#, Paik I, Hanke S, Keim S, Hermann H-M, Wolf L, Hiss M, Becker C, Huq E, Rensing SA, Hiltbrunner A* (2017).
  Plant Cell 29: 310-330.
  * corresponding authors; # equally contributing first authors
• Phytochrome B integrates light and temperature signals in Arabidopsis.
  Legris M, Klose C, Burgie ES, Costigliolo C, Neme M, Hiltbrunner A, Wigge PA, Schäfer E, Vierstra RD, Casal JJ (2016).
  Science 354: 897-900.
• Light-activated phytochrome A and B interact with members of the SPA family to promote photomorphogenesis in Arabidopsis by reorganizing the COP1/SPA complex.
  Sheerin DJ, Menon C, zur Oven-Krockhaus S, Enderle B, Zhu L, Johnen P, Schleifenbaum F, Stierhof YD, Huq E, Hiltbrunner A (2015).
  Plant Cell. 27(1):189-201.
• An evolutionarily conserved signaling mechanism mediates far-red light responses in land plants.
  Possart A, Hiltbrunner A (2013).
  Plant Cell 25:102-114.
• Photoconversion and nuclear trafficking cycles determine phytochrome A's response profile to far-red light.
  Rausenberger J, Tscheuschler A, Nordmeier W, Wüst F, Timmer J, Schäfer E, Fleck C*, Hiltbrunner A* (2011).
  Cell 146: 813-825.
• The major protein import receptor of plastids is essential for chloroplast biogenesis.
  Bauer J*, Chen K*, Hiltbrunner A*, Wehrli E, Eugster M, Schnell DJ, Kessler F (2000).
  Nature 403, 203-207. doi: 10.1038/35003214
  * equally contributing first authors