RT Journal Article
SR Electronic
T1 CRISPR-Cas9-mediated knockout of <em>CYP79D1</em> and <em>CYP79D2</em> in cassava attenuates toxic cyanogen production
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.10.08.462827
DO 10.1101/2021.10.08.462827
A1 Michael A. Gomez
A1 Kodiak C. Berkoff
A1 Baljeet K. Gill
A1 Anthony T. Iavarone
A1 Samantha E. Lieberman
A1 Jessica M. Ma
A1 Alex Schultink
A1 Stacia K. Wyman
A1 Raj Deepika Chauhan
A1 Nigel J. Taylor
A1 Brian J. Staskawicz
A1 Myeong-Je Cho
A1 Daniel S. Rokhsar
A1 Jessica B. Lyons
YR 2021
UL http://biorxiv.org/content/early/2021/10/08/2021.10.08.462827.abstract
AB Cassava (Manihot esculenta Crantz) is a starchy root crop that supports over a billion people in tropical and subtropical regions of the world. This staple, however, produces toxic cyanogenic compounds and requires processing for safe consumption. Excessive consumption of insufficiently processed cassava, in combination with protein-poor diets, can have neurodegenerative impacts. Reducing the cyanogen content by conventional breeding is problematic due to the heterozygous nature of the crop; recombination will generally disrupt a clonally propagated cultivar’s suite of desirable traits. To reduce cyanide levels in cassava, we used CRISPR-mediated mutagenesis to disrupt the cytochrome P450 genes CYP79D1 and CYP79D2 whose protein products catalyze the first step in cyanogenic glucoside biosynthesis. Knockout of both genes eliminated cyanide in leaves and storage roots of cassava accession 60444 and the West African, farmer-preferred cultivar TME 419. Although knockout of CYP79D2 alone resulted in significant reduction of cyanide, mutagenesis of CYP79D1 did not, indicating these paralogs have diverged in their function. Our work demonstrates cassava genome editing for food safety, reduced processing requirements, and environmental benefits that could be readily extended to other farmer-preferred cultivars.Competing Interest StatementThe University of California Regents have filed for protection of intellectual property related to CRISPR/Cas around the world.