A recent discovery from the plant scientists of the Universities of Cambridge and Bordeaux reveals a gene that might be able to widen a nutrient trafficking bottleneck, which has the potential to increase crop yields. Different strategies to sustainably increase crop yields has been a quest for many plant scientists around the world. The search for such kind of knowledge could contribute to the next green revolution. This would include increasing the efficiency of how plants would transport sugars, proteins, and other organic nutrients between the different parts of a plant.

According to the new study, understanding the factors that affect local and long-distance transport within a plant is a step towards aiding plant biotechnologists to come up with a breed of plants that are more productive. The scientists are looking into the possibility to direct transport of organic nutrients to specific parts of the plant that are harvested such as seeds, fruits, and storage tubers.

Professor Yrjö Helariutta, Together with a team of researchers from the Sainsbury Laboratory Cambridge University (SLCU) and Dr. Emanuelle Bayer's team at the University of Bordeaux /CNRS have worked together in the discovery of the Phloem Unloading Modulator (PLM). Their discovery is an oval gene that affects nutrient trafficking by working to alter the channels that connected neighboring plant cells called plasmodesmata. Their research shows that these nanoscale membrane-lined channels that traverse the cell wall barrier to link plant cells together are enabling the transfer of many essential substances.

The study has revealed that mutant plants Arabidopsis thaliana that are missing the PLM gene were found to release more substances at the tip of the roots from the phloem.

For the study, scientists have used a fluorescent protein as a proxy for macromolecules. This has enabled the team to see the PLM gene that was having a clear controlling effect on the number of nutrients unloaded from the phloem.

Dr. Dawei Yan, the lead author of the study from Cambridge's Sainsbury Laboratory explained that mutating PLM would relieve a trafficking bottleneck which has previously reduced the outward movement of nutrients from the vascular system to the rapidly growing tissues in the plant roots.

The team further explained that the PLM is specifically acting at the interface between the phloem pole pericycle (PPP) and endodermal cells. This interface is important for the radio movement of substances after unloading the nutrients. By eliminating the PLM gene, the plants would be able to transport nutrients to where they are needed more rapidly and efficiently.

As there is increased unloading of nutrients, it has been observed that the root in the mutant plants grew faster and longer. The research paper was published recently in the journal Nature Plants.