Dioscorea zingiberensis, a type of yam in China, is a major pharmaceutical
plant that produces diosgenin, a raw material for steroidal hormones. To
date, there is no genome editing approach reported for D. zingiberensis. The
CRISPR-Cas9 system proved to be an efficient targeted genome modification
tool and has been successfully applied in many plants. The team of Shan Feng
from Wuhan University in China, aimed to apply the CRISPR-Cas9 system in D.
The team designed a guide RNA to target the farnesyl pyrophosphate synthase
gene (Dzfps), which is a critical gene involved in the synthesis of
secondary metabolites. High frequencies of mutants were detected in T0
plants. Among the transformed plants, nine mutants that contained mutations
at the predicted site were identified. The transcript levels of Dzfps, was
significantly decreased, leading to a decrease in the content of squalene in
the isolated mutants compared to wildtype plants.
The study revealed that CRISPR-Cas9 can be an effective approach for genome
modification in D. zingiberensis.