Plant & zo
The science of plants and more
Only welcome during shortage
One of the plants challenges is to find enough nutrients for growth. Especially finding enough nitrogen and phosphate can be challenging. A plant needs a lot of these building blocks. But working together with fungi and bacteria can help to acquire more nitrogen or phosphate. But this partnership comes with a price tag. Sugars in exchange for phosphate or nitrogen. Therefore, a plant only works together when there is a nutrient shortage. But how do plants distinguish between the different conditions. Researchers for the UK found out how barley does this.
First, they figured out which signalling molecules from fungi elicited a partnership reaction from barley. They noticed that when barely had a shortage of phosphate or nitrogen both CO and LCO fungal sugars elicited a reaction. While CO-sugars also elicited a clear reaction when there was plenty of nitrogen or phosphate, barley only reacted to LCO-sugars when there was a shortage.
Subsequently, the researchers analysed which of the gene on-switches are needed to initiate the partnership and are switched on themselves as a result of phosphate or nitrogen shortage. This, it turned out, were NSP1 and NSP2. The researchers noticed that barley plants without NSP1 and NSP2 did not initiate partnerships with the fungi.
Recognising fungal signals only during shortage
NSP1 and NSP2 switch-on genes needed for the production of the plant hormone strigolactone and comparable molecules. Therefore, the researchers analysed the effect these molecules on the plant-fungi partnership. They noticed that plants without any ability to perceive strigolatones still initiated plant-fungi partnerships. But when the researchers removed a receptor for an on strigolactone-like molecule, karrikin, then LCO-sugars would not initiate a reaction, and the plant doesn’t initiate plant-fungi partnerships.
After recognising karrikin, the karrikin receptor makes sure that the genes for recognising the LCO-sugars are turned on. In this was the plant makes sure that only when it has not enough nitrogen or phosphate it will recognise the signals for initiating a partnership with beneficial fungi. To get in exchange for sugars some nitrogen or phosphate.
Xin-Ran Li, Jongho Sun, Doris Albinsky, Darius Zarrabian, Raphaella Hull, Tak Lee, Edwin Jarratt-Barnham, Chai Hao Chiu, Amy Jacobsen, Eleni Soumpourou, Alessio Albanese, Wouter Kohlen, Leonie H. Luginbuehl, BrunoGuillotin, TomLawrensen, Hui Lin, Jeremy Murray, Emma Wallington, Wendy Harwood, Jeongmin Choi, Uta Paszkowski and Giles E. D. Oldroyd (2022) Nutrient regulation of lipochitooligosaccharide recognition in plants via NSP1 and NSP2. Nature Communications 13, 6421. https://doi.org/10.1038/s41467-022-33908-3