该研究首次在植物中实验证明了染色质的开放性与Cas9的编辑效率正相关。更重要的是，该研究通过Cas9-TV/dsgRNA策略提高染色质开放性增强体内Cas9编辑效率，为提高体内Cas9编辑效率提供了一种新方法，特别对位于染色质紧密区域基因的编辑具有重要意义。上述研究成果已于近日在Genome Biology 在线发表，题目为Modulating chromatin accessibility by transactivation and targeting proximal dsgRNAs enhances Cas9 editing efficiency in vivo。中国科学院微生物研究所植物基因组学国家重点实验室博士生刘关稳和助理研究员尹康权为共同第一作者，邱金龙研究员为论文的通讯作者。该研究受到农业部、科技部和中科院的经费资助。
摘要：
The CRISPR/Cas9 system is unable to edit all targetable genomic sites with full efficiency in vivo. We show that Cas9-mediated editing is more efficient in open chromatin regions than in closed chromatin regions in rice. A construct (Cas9-TV) formed by fusing a synthetic transcription activation domain to Cas9 edits target sites more efficiently, even in closed chromatin regions. Moreover, combining Cas9-TV with a proximally binding dead sgRNA (dsgRNA) further improves editing efficiency up to several folds. The use of Cas9-TV/dsgRNA thus provides a novel strategy for obtaining efficient genome editing in vivo, especially at nuclease-refractory target sites.
