Scientists at the Queensland University of Technology (QUT) in Australia have discovered a gene in an ancient Australian native tobacco plant that they say is the key to growing crops in space. The plant, Nicotiana benthamiana, has long been used in labs around the world to test viruses and vaccines due to the fact it has no immune system. Surprisingly, this trait has also led to the plant being extremely resilient, which is where space-based food production comes in.
Although the lack of an immune system leaves the plant prone to disease, it frees up energy that would otherwise be used for defense to be used to germinate and grow faster and produce bigger seeds. While this isn’t necessarily advantageous in pathogen-rich environments, it does help the plant, which is known as Pitjuri to indigenous Aboriginal tribes, deal with its primary predator in the Granites area near the border of Western Australia and the Northern Territory – drought.
It is the plant’s ability to rapidly set seed after even small amounts of rain that has helped it survive in the harsh Central Australia climate for around 750,000 years. It is also this rapid growing and germination ability that, if transferred to other plants, would be beneficial in sterile environment of space where there are no pathogens for it to contend with.
The genetic discovery also holds tremendous promise back on Earth in the field of genetic research. The plant’s lack of an immune system has already made it a staple in molecular labs around the world because it will readily take genes introduced into it, while its rapid growth rate helps speed up research in testing vaccines and viruses. It was recently used to create an experimental antibody for the Ebola virus that was trialled on two French aid workers.
"This plant is the 'laboratory rat' of the molecular plant world," says Professor Peter Waterhouse, a plant geneticist at QUT. "We think of it as a magical plant with amazing properties."
The researchers liken the plant to "nude mice". These are lab mice that have a genetic mutation that results in a greatly reduced number of T cells and therefore an inhibited immune system. This means the mice don't mount a rejection response when receiving different types of tissue and tumor grafts, making them ideals for use in medical research.
The team's discovery of the gene responsible for the plant's lack of an immune system means it is now possible to transfer this trait to other plants.
"Scientists can now know how to turn other species into 'nude mice' for research purposes," says Prof. Waterhouse. "So just as nude mice can be really good models for cancer research, 'nude' versions of crop plants could also speed up agricultural research."
Additionally, Prof. Waterhouse says the fact that N. benthamiana produces large seeds makes it an ideal candidate for commercial use as a biofactory. This is because seeds can be used to make antibodies for pharmaceutical use, and the larger the seed, the greater the antibody yield.
The team's paper appears in the journal Nature Plants.
Prof. Waterhouse and lead researcher Dr Julia Bally explain the breakthrough in the video below.
Source: QUT