Ly Diem Nguyen Phuoc, Iqbal Sadia, Fosu-Nyarko John, Milroy Stephen, Jones Michael G K
Crop Biotechnology Research Group, School of Agricultural Sciences, College of Environmental and Life Sciences, Murdoch University, Perth, WA 6150, Australia.
State Agricultural Biotechnology Centre, Centre for Crop and Food Innovation, Food Futures Institute, Murdoch University, Perth, WA 6150, Australia.
Plants (Basel). 2023 Jan 13;12(2):379. doi: 10.3390/plants12020379.
Storing potato tubers at cold temperatures, either for transport or continuity of supply, is associated with the conversion of sucrose to reducing sugars. When cold-stored cut tubers are processed at high temperatures, with endogenous asparagine, acrylamide is formed. Acrylamide is classified as a carcinogen. Potato processors prefer cultivars which accumulate fewer reducing sugars and thus less acrylamide on processing, and suitable processing cultivars may not be available. We used CRISPR-Cas9 to disrupt the genes encoding vacuolar invertase () and asparagine synthetase 1 () of cultivars Atlantic and Desiree to reduce the accumulation of reducing sugars and the production of asparagine after cold storage. Three of the four guide RNAs employed induced mutation frequencies of 17-98%, which resulted in deletions, insertions and substitutions at the targeted gene sites. Eight of ten edited events had mutations in at least one allele of both genes; for two, only the was edited. No wild-type allele was detected in both genes of events DSpco7, DSpFN4 and DSpco12, suggesting full allelic mutations. Tubers of two Atlantic and two Desiree events had reduced fructose and glucose concentrations after cold storage. Crisps from these and four other Desiree events were lighter in colour and included those with 85% less acrylamide. These results demonstrate that multiplex CRISPR-Cas9 technology can generate improved potato cultivars for healthier processed potato products.
将马铃薯块茎冷藏，无论是用于运输还是保持供应的连续性，都与蔗糖向还原糖的转化有关。当冷藏的切块块茎在高温下加工时，与内源性天冬酰胺一起，会形成丙烯酰胺。丙烯酰胺被归类为致癌物。马铃薯加工商更喜欢积累较少还原糖、因此加工时产生较少丙烯酰胺的品种，而合适的加工品种可能并不存在。我们使用CRISPR-Cas9技术破坏大西洋和德西蕾品种中编码液泡转化酶（）和天冬酰胺合成酶1（）的基因，以减少冷藏后还原糖的积累和天冬酰胺的产生。所采用的四个向导RNA中有三个诱导的突变频率为17%-98%，这导致了目标基因位点的缺失、插入和替换。十个编辑事件中有八个在两个基因的至少一个等位基因中发生了突变；有两个事件只编辑了。在事件DSpco7、DSpFN4和DSpco12的两个基因中均未检测到野生型等位基因，表明发生了完全等位基因突变。两个大西洋和两个德西蕾事件的块茎在冷藏后果糖和葡萄糖浓度降低。来自这些事件以及其他四个德西蕾事件的薯片颜色更浅，其中包括丙烯酰胺含量降低85%的薯片。这些结果表明，多重CRISPR-Cas9技术可以培育出改良的马铃薯品种，用于生产更健康的马铃薯加工产品。
