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bioRxiv · 10.1101/2020.07.16.206813

CRISPR-Cas9-mediated editing of myb28 impairs glucoraphanin accumulation of Brassica oleracea in the field

Neequaye, M.·Stavnstrup, S.·Lawrenson, T.·Hundleby, P.·Troncoso-Rey, P.·Saha, S.·Harwood, W.·Traka, M.·Mithen, R.·Ostergaard, L.
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Abstract

We sought to quantify the role of MYB28 in the regulation of aliphatic glucosinolate biosynthesis and associated sulphur metabolism in field-grown B. oleracea with the use of CRISPR-Cas9-mediated gene editing technology. We describe the first characterised myb28 knockout mutant in B. oleracea, and the first UK field trial of CRISPR-Cas9-mediated gene edited plants under the European Court of Justice interpretation of the 2001/18 EU GMO directive. We report that knocking-out myb28 results in downregulation of aliphatic glucosinolate biosynthesis genes and reduction in accumulation of the methionine-derived glucosinolate, glucoraphanin, in leaves and florets of field-grown myb28 mutant broccoli plants. There were no significant changes to the accumulation of sulphate, S-methyl cysteine sulfoxide and indole glucosinolate in leaf and floret tissues.

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Neequaye, M., Stavnstrup, S., Lawrenson, T., Hundleby, P., Troncoso-Rey, P., Saha, S., Harwood, W., Traka, M., Mithen, R., Ostergaard, L.. 2020-07-17. CRISPR-Cas9-mediated editing of myb28 impairs glucoraphanin accumulation of Brassica oleracea in the field. https://doi.org/10.1101/2020.07.16.206813

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