Resurrect Bio Changes the Code To Unlock Plant Defences

Plants have a sophisticated immune system that has co-evolved as a defence against pathogens, but it may be lying inactive in many crop varieties. Now Resurrect Bio, a spinout from The Sainsbury Laboratory (TSL) in Norwich, has found a way to re-engineer the disease response mechanism in plants to restore resilience.

Speaking at Agri-TechE’s REAP conference, Dr Cian Duggan, co-founder of Resurrect Bio, says: “Our research suggests there could be a multitude of resistance genes sitting in crop genomes that are suppressed by pathogens, and that we could potentially resurrect or otherwise improve. This intriguing possibility drove us to establish a spinout company.”

Resurrect Bio has been established to commercialise research from Professor Sophien Kamoun’s laboratory at TSL. Cian set up the company after he was awarded the Innovate UK Young Innovators award, and the team has just started an Innovate UK funded project to develop aphid resistant sugar beet. This aims to prevent the spread of a devastating plant virus transmitted by aphids.

Plants can fight back against pathogens by having receptors, inside their cells and on the surface, that can detect proteins called effectors secreted by the pathogens and simulate the plant’s immune response. For example, initiating rapid cell death at the site of infection to prevent the spread of infection.

Researchers have found that the intracellular receptors are extraordinarily diverse in plant germplasm, and this has created a new approach for studying disease resistance.

The ‘holy grail’ would be to find a way to modify the plant receptors, so they are able to detect new strains of disease and outsmart the pathogen’s ability to mutate.

Research by Professor Sophien Kamoun’s laboratory at the TSL has discovered a mechanism to do this.

Previous discoveries had shown that in the lab plant Arabidopsis, a relative of many crop plants, there is a structural change in a plant receptor in response to a pathogen effector. Alpha helix proteins are activated and flip out to form a funnel-like shape that delivers calcium ions as part of the immune response.

Researchers at TSL found that intracellular receptors, known as NLRs (Nucleotide-binding Leucine-rich Repeat proteins) have a similar action in modern crop plants.

However, in some cases a pair of NLR are required, one to provide pathogen detection (sensor activity) and another to initiate immune signalling (helper or executor activity).  The team found that it was likely that NLR pairs evolved from the multifunctional singletons.

They then discovered that pathogens can exploit the need for pairs of receptors. For example, the potato nematode releases a protein that prevents the helper changing structurally. In this way the nematode can prevent the transformation and disable the immune response.

By understanding this mechanism, it has been possible for the researchers to introduce a mutation in the hinge region of the helper to stop the nematode protein from binding.

This research has shown it is possible to restore (resurrect) the immune response in plants to major pests such as nematodes.

Cian explains that it was following this proof of concept in potatoes, that Resurrect Bio was spunout and it is working to replicate these findings for Soybean Cyst Nematode and Asian Soybean Rust which collectively cost the US more than $2Bn annually.

“Essentially, we have resurrected resistance genes by bioengineering the helper receptor.

“And this doesn’t just apply to a specific gene; it can be implemented with a host of other resistance genes. This is a huge breakthrough and has potential to be a game-changer in plant protection.”

Cian has teamed up with Prof Kamoun and Dr Tolga Bozkurt, from Imperial College London, to commercialise this novel approach to plant protection through Resurrect Bio.