[대학원 생명과학과 세미나 안내]
연사 : 엄준섭 박사(경희대학교 생명공학원)
연제 : SWEET-mediated broad-spectrum bacterial blight resistance and diagnostic kit in rice
일시 : 2020년 2월 11일 (화) 오전 11시
장소 : 하나과학관 A동 103호
초청교수 : 오은규 교수
Abstract
Bacterial blight of rice is an important disease in Asia and Africa. The pathogen, Xanthomonas oryzae pv. Oryzae (Xoo), secretes one or more of six known transcription-activator-like effectors (TALes) that bind specific promoter sequences and induce, at minimum, one of the three host sucrose transporter genes SWEET11, SWEET13 and SWEET14, the expression of which is required for disease susceptibility. We used CRISPR-Cas9-mediated genome editing to introduce mutations in all three SWEET gene promoters. A total of five promoter mutations were simultaneously introduced into the rice line Kitaake and the elite mega varieties IR64 and Ciherang-Sub1. Effector-binding elements (EBEs) variants cannot be recognized by TALes abrogate induction, causing resistance. Paddy trials showed that genome-edited SWEET promoters endow rice lines with robust, broad-spectrum resistance. We also developed a diagnostic kit to enable analysis of bacterial blight in the field and identification of suitable resistant lines. Specifically, we include a SWEET promoter database, RT-PCR primers for detecting SWEET induction, engineered reporter rice lines to visualize SWEET protein accumulation and knock-out rice lines to identify virulence mechanisms in bacterial isolates. We also developed CRISPR-Cas9 genome-edited Kitaake rice to evaluate the efficacy of EBE mutations in resistance, software to predict the optimal resistance gene set for a specific geographic region, and two resistant ‘mega’ rice lines that will empower farmers to plant lines that are most likely to resist rice blight.