Egorova Anastasiya A, Zykova Tatyana E, Hertig Christian W, Hoffie Iris, Morozov Sergey V, Chernyak Elena I, Rogachev Artem D, Korotkova Anna M, Vikhorev Alexander V, Vasiliev Gennady V, Shoeva Olesya Y, Kumlehn Jochen, Gerasimova Sophia V, Khlestkina Elena K
Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia.
Faculty of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia.
Int J Mol Sci. 2024 Nov 26;25(23):12705. doi: 10.3390/ijms252312705.
Blue barley grain pigmentation results from anthocyanin accumulation in the aleurone layer. Anthocyanins are known for their beneficial effects on human health. The gene encoding the MYELOCYTOMATOSIS 2 (MYC2) transcription factor is potentially responsible for the blue coloration of the aleurone. In non-pigmented barley, a single nucleotide insertion in this gene causes a frameshift mutation with a premature stop codon. It was hypothesized that restoring the reading frame could activate anthocyanin accumulation in the aleurone. Using a targeted mutagenesis approach in the present study, the reading frame of was restored in the non-pigmented cultivar Golden Promise. Genetic constructs harboring and expression units were developed, pre-validated in protoplasts, and then functional alleles were generated at the plant level via -mediated transformation. Anthocyanin accumulation in the aleurone layer of grains from these mutants was confirmed through microscopy and chemical analysis. The expression of anthocyanin biosynthesis genes was analyzed, revealing that the restoration of MYC2 led to increased transcript levels of and genes. These results confirm the critical role of the MYC2 transcription factor in the blue aleurone trait and provide a biotechnological solution for enriching barley grain with anthocyanins.
蓝色大麦籽粒色素沉着是由于糊粉层中花青素的积累所致。花青素因其对人体健康的有益作用而闻名。编码髓细胞瘤2（MYC2）转录因子的基因可能是导致糊粉层呈现蓝色的原因。在无色素大麦中，该基因中的一个单核苷酸插入导致移码突变并产生提前终止密码子。据推测，恢复阅读框可以激活糊粉层中花青素的积累。在本研究中，采用靶向诱变方法，在无色素品种金色承诺（Golden Promise）中恢复了MYC2的阅读框。构建了含有MYC2和表达单元的遗传构建体，在原生质体中进行了预验证，然后通过农杆菌介导的转化在植物水平上产生了功能性等位基因。通过显微镜检查和化学分析证实了这些突变体籽粒糊粉层中花青素的积累。对花青素生物合成基因的表达进行了分析，结果表明，MYC2的恢复导致了和基因转录水平的增加。这些结果证实了MYC2转录因子在蓝色糊粉层性状中的关键作用，并为用花青素富集大麦籽粒提供了一种生物技术解决方案。
