Title: Base editing for next generation Breeding
Speaker: Prof. Keiji Nishida ,Graduate School of Science and Technology, Kobe University
Day/Date: Friday/ April 27th, 2018
Host PI: Prof. Yoji Kawano
Venue: NO.1 Conference Room
In place of nuclease activity of conventional genome editing, DNA base-modifying enzymes allow direct introduction of point mutations (base editing). Deaminase-mediated base editing (BE and Target-AID) has been developed by tethering DNA cytidine deaminases to nuclease-deficient CRISPR-Cas9 system, enabling pinpoint mutagenesis within the range of 3-5 bases. It shows much less toxicity compared to full nuclease Cas9 and does not require template DNA for precise genome editing. It is now applicable to wide range of organisms and keep improving. In mammals and plants, use of nickase Cas9 (D10A), which retains single-strand cleaving activity, greatly increased the efficiency, although it also occasionally induced insertion/deletion (indel). Co-expression of Uracil-DNA glycosylase inhibitor (UGI) further improved the efficiency and reduced the indel formation at the same time. In E.coli, dCas9 is preferred and the use of UGI allows multiplex editing of up to 41 loci of multicopy elements. For crop breeding, introducing gain of function mutation has been performed, demonstrating usefulness of the technology.
The seminar will be delivered in English.