RNA interference explained
New Zealand’s Biological Heritage – Ngā Koiora Tuku Iho National Science Challenge is investigating new tools to deal with pests threats, including varroa mites and myrtle rust.
RNA interference (RNAi) is a biological process in which RNA inhibits gene expression. It is a natural process in cells. As a biotechnology tool, RNA interference ‘silences’ a gene by using a synthetic RNA sequence to prevent translation. This genetic modification tool is being trialled overseas as an environmentally friendly alternative to pesticides and fungicides.
Questions for discussion
What is a wicked problem?
What wicked problems does this video address?
Does using double-stranded RNA change the DNA or genome of the species?
The video says, “RNAi happens naturally all the time, but we can also make it happen by applying double-stranded RNA to a plant, animal or fungus. When this happens, it’s an extremely specific process. The double-stranded RNA given to one species is highly unlikely to affect another.”
Why is the double-stranded RNA unlikely to affect another species?
What are your thoughts about this statement?
Transcript
Voiceover
We have some wicked environmental problems to deal with in Aotearoa New Zealand. As you’re watching this video, varroa mites are killing honey bees by the hundreds of thousands.
The only methods we have to combat this at the moment are broad-spectrum pesticides, which kill the varroa mite but can hurt the bees as well.
At the same time, myrtle rus t is slowly making its way across the country – crippling and killing our native trees and vines as it goes.
There is currently no long-term, environmentally safe cure for myrtle rust .
What both of these problems have in common is that they could be solved by using RNA interference .
Most people know what DNA is, but what’s RNA? RNA is the messenger that instructs the cells in any living thing that they need to make proteins. Proteins are the building blocks of life.
When an animal, plant or fungus has enough protein, double-stranded RNA is produced by cells as a stop button: it stops proteins being made.
This is a naturally occurring process called RNA interference or RNAi.
Each stop button is made by a species for that species. Because it’s so specific, the process doesn’t affect other species in the same environment.
RNAi happens naturally all the time, but we can also make it happen by applying double-stranded RNA to a plant, animal or fungus.
When this happens, it’s an extremely specific process. The double-stranded RNA given to one species is highly unlikely to affect another.
So if we introduce double-stranded RNA for varroa mites into a beehive, it could stop the mites reproducing and have no effect on the bees.
This technology is already being used in people for the medical treatment of genetic diseases and cancer. In these cases, RNAi stops the problem proteins being made, which reduces the symptoms of the condition .
Scientists have also found a RNAi process for the myrtle rust fungus in Australia but are still running tests for this in the lab.
We know using double-stranded RNA does not change the DNA or genome of the species involved and it degrades naturally, but there is more research needed before we could use it for conservation or industry.
Ultimately, we could use RNAi to directly target myrtle rus t and varroa mites in Aotearoa. This could save our taonga species and avoid the use of pesticides.
But what do you think?
Acknowledgements
New Zealand’s Biological Heritage – Ngā Koiora Tuku Iho National Science Challenge
