TY  - JOUR
AU  - Qi, Xiantao
AU  - Dong, Le
AU  - Liu, Changlin
AU  - Mao, Long
AU  - Liu, Fang
AU  - Zhang, Xin
AU  - Cheng, Beijiu
AU  - Xie, Chuanxiao
PY  - 2018
TI  - Systematic identification of endogenous RNA polymerase Ⅲ promoters for efficient RNA guide-based genome editing technologies in maize
JO  - The Crop Journal
SN  - 2095-5421
SP  - 314
EP  - 320
VL  - 6
IS  - 3
AB  - Single-guide RNA (sgRNA) is one of the two core components of the CRISPR (clustered regularly interspaced short palindromic repeat)/Cas (CRISPR-associated) genome-editing technology. We established an in vitro Traffic Light Reporter (TLR) system, which is designated as the same colors as traffic lights such as green, red and yellow were produced in cells. The TLR can be readily used in maize mesophyll protoplast for a quick test of promoter activity. The TLR assay indicates the variation in transcription activities of the seven Pol Ⅲ promoters, from 3.4% (U6-1) to over 21.0% (U6-6). The U6-2 promoter, which was constructed to drive sgRNA expression targeting the ZmWx1 gene, yielded mutation efficiencies ranging from 48.5% to 97.1%. Based on the reported and unpublished data, the in vitro TLR assay results were confirmed to be a readily system and may be extended to other plant species amenable to efficient genome editing via CRISPR/Cas. Our efforts provide an efficient method of identifying native Pol Ⅲ-recognized promoters for RNA guide-based genome-editing systems in maize.
UR  - https://doi.org/10.1016/j.cj.2018.02.005
DO  - 10.1016/j.cj.2018.02.005