Tang Wei, Yan Hui, Su Zai-Xing, Park Sung-Chul, Liu Ya-Ju, Zhang Yun-Gang, Wang Xin, Kou Meng, Ma Dai-Fu, Kwak Sang-Soo, Li Qiang
Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District / Key Laboratory for Biology and Genetic Breeding of Sweetpotato (Xuzhou), Ministry of Agriculture / Sweetpotato Research Institute, Chinese Academy of Agricultural Sciences, Kunpeng Road, Xuzhou, Jiangsu 221131, People's Republic of China.
Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District / Key Laboratory for Biology and Genetic Breeding of Sweetpotato (Xuzhou), Ministry of Agriculture / Sweetpotato Research Institute, Chinese Academy of Agricultural Sciences, Kunpeng Road, Xuzhou, Jiangsu 221131, People's Republic of China; Plant Systems Engineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
Plant Physiol Biochem. 2017 Jul;116:27-35. doi: 10.1016/j.plaphy.2017.04.025. Epub 2017 Apr 27.
The transition from vegetative to reproductive growth, a key event in the lifecycle of a plant, is affected by environmental stresses. The flowering-time regulator GIGANTEA (GI) may be contributing to susceptibility of the regulation of photoperiodic flowering, circadian rhythm control, and abiotic stress resistance in Arabidopsis. However, the role of GI in sweet potato remains unknown. Here, we isolated and characterized a GI gene (IbGI) from sweet potato (Ipomoea batatas [L.] Lam). The IbGI cDNA sequence was isolated based on information from a sweet potato transcriptome database. IbGI mRNA transcript levels showed robust circadian rhythm control during the light-dark transition, and the expression of IbGI was stronger in leaves and roots than in stems. IbGI protein is predominantly localized to the nucleus. IbGI expression was upregulated by high temperature, drought, and salt stress but downregulated by cold stress. Overexpressing IbGI in the Arabidopsis gi-2 mutant background rescued its late flowering phenotype and reduced its salt tolerance. Taken together, these results indicate that IbGI shares functions in regulating flowering, the circadian rhythm, and tolerance to some stresses with other GI orthologs.
从营养生长向生殖生长的转变是植物生命周期中的关键事件，受到环境胁迫的影响。开花时间调节因子巨无霸（GI）可能参与了拟南芥光周期开花调控、昼夜节律控制和非生物胁迫抗性的易感性。然而，GI在甘薯中的作用尚不清楚。在此，我们从甘薯（Ipomoea batatas [L.] Lam）中分离并鉴定了一个GI基因（IbGI）。IbGI cDNA序列是基于甘薯转录组数据库中的信息分离得到的。IbGI mRNA转录水平在明暗转换期间表现出强烈的昼夜节律控制，且IbGI在叶和根中的表达强于茎。IbGI蛋白主要定位于细胞核。IbGI的表达在高温、干旱和盐胁迫下上调，但在冷胁迫下下调。在拟南芥gi-2突变体背景中过表达IbGI挽救了其晚花表型并降低了其耐盐性。综上所述，这些结果表明IbGI与其他GI直系同源物在调节开花、昼夜节律和对某些胁迫的耐受性方面具有共同功能。
