Kim So-Eun, Lee Chan-Ju, Park Sul-U, Lim Ye-Hoon, Park Woo Sung, Kim Hye-Jin, Ahn Mi-Jeong, Kwak Sang-Soo, Kim Ho Soo
Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Daejeon 34141, Korea.
Department of Environmental Biotechnology, KRIBB School of Biotechnology, University of Science and Technology (UST), 217 Gajeong-ro, Daejeon 34113, Korea.
Antioxidants (Basel). 2021 Jan 4;10(1):51. doi: 10.3390/antiox10010051.
Carotenoids function as photosynthetic accessory pigments, antioxidants, and vitamin A precursors. We recently showed that transgenic sweetpotato calli overexpressing the mutant sweetpotato ( [L.] Lam) gene (-), which carries a single nucleotide polymorphism responsible for Arg to His substitution at amino acid position 96, exhibited dramatically higher carotenoid content and abiotic stress tolerance than calli overexpressing the wild-type gene (-). In this study, we generated transgenic sweetpotato plants overexpressing - under the control of the cauliflower mosaic virus (CaMV) promoter via -mediated transformation. The total carotenoid contents of - storage roots (light-orange flesh) and - storage roots (light-yellow flesh) were 5.4-19.6 and 3.2-fold higher, respectively, than those of non-transgenic (NT) storage roots (white flesh). The β-carotene content of - storage roots was up to 186.2-fold higher than that of NT storage roots. In addition, - plants showed greater tolerance to heat stress (47 °C) than NT and - plants, possibly because of higher DPPH radical scavenging activity and ABA contents. These results indicate that - is a promising strategy for developing new sweetpotato cultivars with improved carotenoid contents and heat stress tolerance.
类胡萝卜素作为光合辅助色素、抗氧化剂和维生素A前体发挥作用。我们最近发现，过表达突变型甘薯（[L.] Lam）基因（-）的转基因甘薯愈伤组织，该基因在氨基酸位置96处存在一个导致精氨酸替换为组氨酸的单核苷酸多态性，其类胡萝卜素含量和非生物胁迫耐受性显著高于过表达野生型基因（-）的愈伤组织。在本研究中，我们通过农杆菌介导的转化，在花椰菜花叶病毒（CaMV）启动子的控制下，生成了过表达-的转基因甘薯植株。-贮藏根（浅橙色果肉）和-贮藏根（浅黄色果肉）的总类胡萝卜素含量分别比非转基因（NT）贮藏根（白色果肉）高5.4 - 19.6倍和3.2倍。-贮藏根的β-胡萝卜素含量比NT贮藏根高186.2倍。此外，-植株比NT和-植株对热胁迫（47℃）具有更强的耐受性，这可能是由于其更高的DPPH自由基清除活性和脱落酸含量。这些结果表明，-是培育具有更高类胡萝卜素含量和热胁迫耐受性的新甘薯品种的一种有前景的策略。
