How does a plant manage to quickly adapt its growth to changing environmental conditions? A research team at the University of Freiburg led by plant physiologist Prof. Dr. Jürgen Kleine-Vehn has discovered a previously unknown mechanism for this: a kind of cellular degradation machinery acts in the background like a switch that decides whether the plant hormone auxin is available or not. This mechanism enables the plant to react to the environment and dynamically regulate its growth - be it root growth in the soil or shoot curvature towards the light. The results have been published in the journal Science Advances.
· Press Release
Growth switch for adaptability of plants discovered
Researchers from Freiburg have discovered a mechanism by which plant hormones are specifically regulated in order to adapt growth to environmental conditions - controlled by the so-called ERAD machinery. The study has been published in the journal Science Advances. The results could help to make crops more resilient in the future and thus make agriculture more sustainable.
Arabidopsis plant in laboratory conditions. Photo: Jürgen Kleine-Vehn
PILS proteins as gatekeepers
At the centre of the newly discovered control mechanism are the so-called PILS proteins. They act like gatekeepers: sometimes they hold back auxin inside the cell, sometimes they release it for growth. Which decision is made depends on how many of these proteins are present. The Freiburg researchers have now been able to show that a cellular degradation machinery, the so-called ERAD machinery, regulates the number of PILS proteins as required. If auxin is required when the environment changes, the gatekeepers are degraded - the plant changes its growth mode. Under stable conditions, on the other hand, the proteins remain in place and slow down the hormone response.
Prof. Dr. Jürgen Kleine-Vehn
Professor of Molecular Plant Physiology at the Faculty of Biology at the University of Freiburg and member and spokesperson of the Cluster of Excellence CIBSS
“You can think of this mechanism as a molecular switch: the plant decides whether auxin works or not - and thus flexibly adapts its growth to the environment”
Possible key to sustainable agriculture
‘You can think of this mechanism as a molecular switch,’ says study leader Kleine-Vehn. ‘The plant decides whether auxin works or not - and thus flexibly adapts its growth to the environment.’ The discovery opens up a new perspective on the fine control of plant development. It shows how closely internal control mechanisms and external signals are intertwined.
Seinab Noura, biologist at the University of Freiburg and first author, also emphasises the importance of the results: ‘If we make targeted use of such mechanisms, crops could become more resistant to stress.’ In the long term, this knowledge could also help to make plants more resilient to climate change - a key to sustainable agriculture in the future.
Original Publication:
Seinab Noura, Jonathan Ferreira Da Silva Santos, Elena Feraru, Sebastian N.W. Hoernstein, Mugurel I. Feraru, Laura Montero-Morales, Ann-Kathrin Rößling, David Scheuring, Richard Strasser, Pitter F. Huesgen, Sascha Waidmann, Jürgen Kleine-Vehn: ERAD machinery controls the conditional turnover of PIN-LIKES in plants. In: Science Advances. DOI: https://doi.org/10.1126/sciadv.adx5027