[2016-09-29] Humans adjust to weather changes by changing their clothes or changing their location. Plants have developed other strategies to adapt to a changing environment. Louise Norén Lindbäck from Umeå Plant Science Centre has detected new ways how plants sense changes in their environment and how they communicate these changes within the plant cell. She will defend her findings on the 6th of October. 

Louise Norén LindbäckPhoto: Carole DubreuilLouise Norén Lindbäck has identified a new mechanism that is controlled by signaling molecules of the chlorophyll biosynthesis. These molecules are called tetrapyrroles. They can activate a signal transmitted from the chloroplast, the place where chlorophyll is synthesized in the cell and photosynthesis takes place, to the nucleus. This signal from the chloroplast informs the nucleus about which genes need to be turned on or off to adapt the cell machinery to changes in the environment.

”This new signaling pathway is important both under normal conditions for fine-tuning the protein synthesis during the day as well as under extreme conditions to protect the plant against for instance too much light”, says Louise Norén Lindbäck. ”We humans can go inside or take on/off our clothes to adapt to changes of the weather. Plants do it by producing special proteins that can help to protect their cells against excessive sunlight”.

The chloroplast is talking constantly with the nucleus of the cell but this is not a one-way communication. Signals go back and forth all the time. Like this the two cell compartments discuss which proteins are needed when and where to adapt best to changes in the environment. The sunlight is a key factor in this communication. It does not only deliver the energy which is driving photosynthesis. The sunlight informs the plant also about e.g. the time of the day or the season of the year.

Louise Norén Lindbäck has used the model plant thale cress (Arabidopsis thaliana) to study the molecules and proteins that are important for the chloroplast and the nucleus of the cell to communicate with each other. Besides tetrapyrroles, she has also identified specific proteins in the cell nucleus that control the activation of certain genes regulating chloroplast development. These proteins are especially important for a germ that comes out of the soil and needs to adjust its metabolism to the light.

It is very crucial for a plant to be able to adjust its growth to a changing environment and this becomes even more important in times of climate change. The communication of those changes within the cell plays a key role in the adaptation process of plants. Louise Norén Lindbäck’s findings will help to understand better how plants survive when the climate is changing. 

Louise Norén Lindbäck grew up in Skellefteå. She studied molecular biology at Umeå University and has done her PhD thesis at the Umeå Plant Science Centre. 

An electronic version of the thesis is pulished here: 
Coordination of two different genomes in response to light and stress

Link to the swedish press release from Umeå University

For more information, please contact:
Louise Norén Lindbäck, Department of Plant Physiology, Umeå University
Telefon: 073-8169511 
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Information about the public defence of the dissertation:

On Thursday the 6th of October, Louise Norén Lindbäck, Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, will defend her dissertation entitled:
Coordination of two different genomes in response to light and stress. The public defence of the dissertation will be at 10:00 in KB3A9 (small lecture room), in the KBC Building.

Faculty opponent is Dr. Antony Dodd, School of Biological Sciences, University of Bristol, Bristol, UK.