Samantha Lieberman

CRISPR-Cas9-mediated genome editing to reduce levels of cyanide in cassava

In tropical regions around the world, the cassava plant’s starchy tuberous roots are relied on as a staple source of calories. The crop is naturally drought tolerant and can be stored underground for extended periods of time – preventing the need for immediate harvesting and storage. However, prior to consumption, cassava requires significant processing due to the cyanogenic glucosides that it naturally produces. The cyanogenic glucosides linamarin and lotaustralin are synthesized in the leaves of the cassava plant and transported basipetal in the plant to the tuberous roots. The cassava genes CYP79D1 and CYP79D2 encode the enzyme responsible for the first step of the cyanogenic glucoside biosynthetic pathway. Downregulation of these genes should lead to a reduction in cyanide content in cassava leaves and tuberous roots. Therefore: the goal of this project is to use CRISPR-Cas9 gene editing technology to engineer non-toxic varieties of cassava by causing knockouts in the CYP79D1 and CYP79D2 genes. Successful mutant plants will not produce linamarin and lotaustralin and therefore will be safe to consume without processing.

Message to Sponsor

I am very grateful to have been selected for the SURF Rose Hills Experience Fellowship. I would like to think that the incremental steps we are taking towards engineering a cyanogenic glucoside free variety of cassava may one day amount to work much bigger than myself and feed and protect people from the detrimental effects of the cyanide toxin. Thank you for believing in my work. I am very excited for all the learning opportunities this summer holds.
  • Major: Genetics and Plant Biology
  • Sponsor: Rose Hill Foundation
  • Mentor: Jessica Lyons