Plant Photoreceptor-Mediated Signal Transduction

Both genetic and environmental factors influence growth and development of any living organism. Plant development is very plastic and is constantly modulated by environmental fluctuations. Being photoautotrophic plants are particularly sensitive to their light environment. Light affects all aspects of the plant life cycle. To optimize growth according to ambient light conditions plants evolved several classes of photoreceptors including the UV-A/blue light sensing cryptochromes and phototropins and the phytochromes maximally absorbing red/far-red light. The coordinated action of all these light receptors allows plants to fine-tune their development.

We focus our attention on two characteristic plant responses to light: phototropism which is the ability of plant stems to reorient their growth towards a unilateral source of light and shade avoidance which in shade intolerant plants such as Arabidopsis triggers elongation growth responses enabling the plant to reach unfiltered sunlight. Both light-responses contribute to the maximization of plant growth in particular in low light conditions that are typical in dense plant populations.

• Changes in resource partitioning between and within organs support growth adjustment to neighbor proximity in Brassicaceae seedlings
  de Wit, M; George, GM; Ince, YC; Dankwa-Egli, B; Hersch, M; Zeeman, SC; Fankhauser, C
  PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 115 (42):E9953-E9961; 10.1073/pnas.1806084115 OCT 16 2018
• Arabidopsis RUP2 represses UVR8-mediated flowering in noninductive photoperiods
  Arongaus, AB; Chen, S; Pireyre, M; Glockner, N; Galvao, VC; Albert, A; Winkler, JB; Fankhauser, C; Harter, K; Ulm, R
  GENES & DEVELOPMENT, 32 (19-20):1332-1343; 10.1101/gad.318592.118 OCT 1 2018
• A phosphorylation switch turns a positive regulator of phototropism into an inhibitor of the process
  Schumacher, P; Demarsy, E; Waridel, P; Petrolati, LA; Trevisan, M; Fankhauser, C
  NATURE COMMUNICATIONS, 9 10.1038/s41467-018-04752-1 JUN 19 2018
• The influence of greenhouse-integrated photovoltaics on crop production 
  Allardyce, Claire S.; Fankhauser, Christian; Zakeeruddin, Shaik M.; et al. 
  SOLAR ENERGY, 155: 517-522 10.1016/j.solener.2017.06.044 OCT 2017
• Low number of fixed somatic mutations in a long-lived oak tree 
  Schmid-Siegert, Emanuel; Sarkar, Namrata; Iseli, Christian; et al. 
  NATURE PLANTS, 3 (12): 926-929 10.1038/s41477-017-0066-9 DEC 2017

• Responses of plants to their light environment
• Plant photoreceptors and signal transduction mechanisms
• Phototropism
• Shade avoidance
• Role of the circadian clock in plant growth responses

• NCCR “Plant Survival” chloroplast responses to changing light conditions.
• SystemsX.ch “Plant growth in a changing environment”. Effects of the biotic and abiotic (e.g. light) environment on plant growth.
• Modeling of photoreceptor-mediated growth responses in collaboration with mathematicians and bio-informatitians.
• Development of imaging systems to record plant growth with high temporal and spatial resolution
• Genome-wide regulation of gene expression