Abstract

As awareness of climate change and the need for a more plant based diet spreads, so has interest in novel protein sources. One crop that has been gaining interest in the protein field is potato. Especially potatoes grown for the starch industry have been discussed since tuber proteins are accumulated in one of the side streams of starch processing. 

In this thesis, I discuss the potential of using precision editing technologies such as base editing and prime editing to modify potato proteins to make this under-utilized resource available. Starting with patatin, a protein that is already a by-product from starch industry. It was shown that several patatin genes can be targeted at once using CRISPR/Cas9, meaning the family is a viable target. Furthermore, expression analysis showed that a majority of transcripts were represented by only a few genes, suggesting that total gene coverage is unnecessary.  

A second protein of interest, Pho1a, was investigated. While one of the most abundant proteins in potato tubers, its function remains the source of much debate. Mutant lines deficient in Pho1a activity were produced and analysed for phenotypic effects, showing low amylose content and small starch granules. Since these are detrimental traits in starch production, Pho1a, could be an interesting target for enhancing edits in the future. 

Finally, a gene editing toolbox was developed, utilizing adapter proteins to allow modular assembly of fusion constructs for CRISPR/Cas editing. It was shown that addition of the adapter domains did not affect Cas9 efficiency. While initial experiments using prime editing were unsuccessful, the underlying principles remain robust.

Keywords

Gene editing; CRISPR/Cas; synthetic biology; protein engineering; protein stability; Solanum tuberosum; starch potato cultivars; tuber protein; patatin

Published in

Acta Universitatis Agriculturae Sueciae
2024, number: 2024:48ISBN: 978-91-8046-036-1, eISBN: 978-91-8046-037-8
Publisher: Swedish University of Agricultural Sciences

SLU Authors

• Friberg, Martin

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Plant Biotechnology


Publication identifier

DOI: https://doi.org/10.54612/a.3u7o51prv7

Permanent link to this page (URI)

https://res.slu.se/id/publ/128767