Samantha Lieberman Rose Hills
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.