Research Reveals How Hormones Promote Plant Growth

Michael Hothorn from the Friedrich-Miescher-Laboratory of the Max Planck Society in Tübingen and his team revealed in their latest work that a plant membrane receptor requires a helper protein to sense a growth-promoting steroid hormone and to transduce this signal across the cell membrane.

Plant membrane receptors look drastically different from animal and bacterial membrane receptors. The plant steroid receptor BRI1, which can sense a small steroid hormone promoting plant growth, belongs to the family of leucine-rich repeat (LRR) receptor kinases, which are responsible for most membrane signaling events in plants.

Researchers in the Hothorn lab showed that BRI1 requires a helper protein to correctly sense the hormone and transduce the signal across the membrane. The helper SERK1 contributes directly to form the hormone binding pocket, with both proteins interacting with the hormone. The steroid acts as a molecular glue which promotes association of the BRI1 and SERK1 LRR domains at the cell surface. This causes interaction of the cytoplasmic kinases domains in the cell interior, which in turn activates a well characterized signaling pathway triggering the growth response.

For more details about this research, read the news release at: http://www.mpg.de/7496997/plant-hormone-receptor?filter_order=L&research_topic.