CRISPR Reveals How Circular RNA Undermines Rice Disease

Researchers from Shanghai Jiao Tong University in China and partners explored the role of circular RNAs in rice and their interaction with pathogenic bacteria. Before their investigation, the regulatory mechanisms of circular RNAs in such interactions were unknown.

Knocking down circular RNAs in plants has been a challenge because their sequences are similar to their parent genes. To address this, the research team developed a CRISPR-Cas13d system to specifically target and reduce the expression of a rice circular RNA named Os-circANK.

The investigation revealed that Os-circANK works like a sponge for a specific microRNA—Osa-miR398b. This action prevents Osa-miR398b from cleaving OsCSD1/OsCSD2, leading to lower levels of reactive oxygen species and decreased resistance to bacterial blight in rice.

The findings provide evidence that Os-circANK plays a negative role in rice resistance to bacterial blight by impacting the Osa-miR398b/OsCSD1/OsCSD2 pathway.