Significant enhancement of fatty acid composition in seeds of the allohexaploid, Camelina sativa, using CRISPR/Cas9 gene editing

Authors

Wen Zhi Jhang, University of Nebraska-Lincoln
Isabelle M. Henry, University of California, Davis
Peter G. Lynagh, University of California, Davis
Lucia Comai, University of California, Davis
Edgar B. Cahoon, University of Nebraska-LincolnFollow
Donald P. Weeks, University of Nebraska-LincolnFollow

Date of this Version

2017

Citation

Jiang, W.Z., Henry, I.M., Lynagh, P.G., Comai, L., Cahoon, E.B. and Weeks, D.P. (2017) Significant enhancement of fatty acid composition in seeds of the allohexaploid, Camelina sativa, using CRISPR/Cas9 gene editing. Plant Biotechnol. J., doi: 10.1111/pbi.12663

Comments

Copyright 2016 The Authors. Used by permission.

Abstract

The CRISPR/Cas9 nuclease system is a powerful and flexible tool for genome editing, and novel applications of this system are being developed rapidly. Here, we used CRISPR/Cas9 to target the FAD2 gene in Arabidopsis thaliana and in the closely related emerging oil seed plant, Camelina sativa, with the goal of improving seed oil composition. We successfully obtained Camelina seeds in which oleic acid content was increased from 16% to over 50% of the fatty acid composition. These increases were associated with significant decreases in the less desirable polyunsaturated fatty acids, linoleic acid (i.e. a decrease from ~16% to <4%) and linolenic acid (a decrease from ~35% to <10%). These changes result in oils that are superior on multiple levels: they are healthier, more oxidatively stable and better suited for production of certain commercial chemicals, including biofuels. As expected, A. thaliana T₂ and T₃ generation seeds exhibiting these types of altered fatty acid profiles were homozygous for disrupted FAD2 alleles. In the allohexaploid, Camelina, guide RNAs were designed that simultaneously targeted all three homoeologous FAD2 genes. This strategy that significantly enhanced oil composition in T₃ and T₄ generation Camelina seeds was associated with a combination of germ-line mutations and somatic cell mutations in FAD2 genes in each of the three Camelina subgenomes.