Li Zhiling, Yu Lili, Umar Abdul Wakeel, Wang Jiaruo, Zhang Jian, Wang Nan, Zhang Min, Yao Na, Ahmad Naveed, Liu Xiuming
College of Life Sciences, Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, Changchun, 130118, China.
BNU-HKUST Laboratory of Green Innovation, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai (BNUZ), Zhuhai, 519087, China.
BMC Plant Biol. 2024 Dec 23;24(1):1232. doi: 10.1186/s12870-024-05943-3.
Safflower thrives in dry environments but faces difficulties with flowering in wet and rainy summers. Flavonoids play a role in flower development and can potentially alleviate these challenges. Furthermore, the FLOWERING LOCUS T (FT) family of phosphatidylethanolamine-binding protein (PEBP) genes play a crucial role in the photoperiodic flowering pathway. However, their direct impact on flowering and flavonoid biosynthesis under different light duration is elusive.
Utilizing the genome sequencing of Safflower (Jihong NO.1), the current study identifies three specific genes (CtFT1, CtFT2, and CtFT3) that exhibit upregulation in response to long-day conditions. The overexpression of CtFT2, displayed an early, whereas CtFT1 and CtFT3 late flowering phenotype in Arabidopsis thaliana. Interestingly, the transient overexpression of CtFT1 in safflower leaves caused early flowering, while overexpressing CtFT2 and CtFT3 led to late flowering. Additionally, overexpressing CtFT3 in Arabidopsis and CtFT1, CtFT2, and CtFT3 in safflower leaves, significantly increased flavonoid synthesis.
These findings showed that overexpression of CtFT genes could affect the flowering time and significantly increase the flavonoid content of safflower. The function of CtFT gene is different in safflower and Arabidopsis. This study provides valuable insights into the role of CtFT genes in flower formation and flavonoid synthesis in safflower, which may help in improving safflower breeding quality and its adaptability to diverse environmental conditions.
红花在干燥环境中生长良好，但在潮湿多雨的夏季开花会面临困难。黄酮类化合物在花的发育中起作用，并且可能缓解这些挑战。此外，磷脂酰乙醇胺结合蛋白（PEBP）基因家族的成花素基因（FLOWERING LOCUS T，FT）在光周期开花途径中起关键作用。然而，它们在不同光照时长下对开花和黄酮类生物合成的直接影响尚不清楚。
利用红花（吉红1号）的基因组测序，本研究鉴定出三个特定基因（CtFT1、CtFT2和CtFT3），它们在长日照条件下表现出上调。CtFT2的过表达在拟南芥中表现出早花表型，而CtFT1和CtFT3则表现出晚花表型。有趣的是，CtFT1在红花叶片中的瞬时过表达导致早花，而过表达CtFT2和CtFT3则导致晚花。此外，在拟南芥中过表达CtFT3以及在红花叶片中过表达CtFT1、CtFT2和CtFT3，显著增加了黄酮类化合物的合成。
这些发现表明，CtFT基因的过表达会影响开花时间，并显著增加红花的黄酮类化合物含量。CtFT基因在红花和拟南芥中的功能不同。本研究为CtFT基因在红花花形成和黄酮类化合物合成中的作用提供了有价值的见解，这可能有助于提高红花育种质量及其对不同环境条件的适应性。
