Folate Biofortification of Potato by Tuber-Specific Expression of Four Folate Biosynthesis Genes

摘要

Insufficient dietary intake of micronutrients,known as "hidden hunger",is a devastating global burden,affecting two billion people.Deficiency of folates (vitamin B9),which are known to play a central role in C1 metabolism,causes birth defects in at least a quarter million people annually.Biofortification to enhance the level of naturally occurring folates in crop plants,proves to be an efficient and cost-effective tool in fighting folate deficiency.Previously,introduction of folate biosynthesis genes GTPCHI and ADCS,proven to be a successful biofortification strategy in rice and tomato,turned out to be insufficient to adequately increase folate levels in potato tubers.Here,we provide a proof of concept that additional introduction of HPPK/DHPS and/or FPGS,downstream genes in mitochondrial folate biosynthesis,enables augmentation of folates to satisfactory levels (12-fold) and ensures folate stability upon long-term storage of tubers.In conclusion,this engineering strategy can serve as a model in the creation of folate-accumulating potato cultivars,readily applicable in potato-consuming populations suffering from folate deficiency.