Down‐regulation of GIGANTEA‐like genes increases plant growth and salt stress tolerance in poplar

• DOI: 10.1111/pbi.12628
• Publication Date: 2016-08-27T07:33:24Z
• Authors: Qingbo Ke; Ho Soo Kim; Zhi Wang; Chang Yoon Ji; Jae Cheol Jeong; Haeng‐Soon Lee; Young‐Im Choi; Bingcheng Xu; Xiping Deng; Dae‐Jin Yun; Sang‐Soo Kwak
• Keywords: Gigantea

The flowering time regulator GIGANTEA (GI) connects networks involved in developmental stage transitions and environmental stress responses Arabidopsis. However, little is known about the role of GI growth, development to challenges perennial plant poplar. Here, we identified functionally characterized three GI-like genes (PagGIa, PagGIb PagGIc) from poplar (Populus alba × Populus glandulosa). PagGIs are predominantly nuclear localized their transcripts rhythmically expressed, with a peak around zeitgeber 12 under long-day conditions. Overexpressing wild-type (WT) Arabidopsis induced early salt sensitivity, while overexpressing gi-2 mutant completely or partially rescued its delayed enhanced tolerance phenotypes. Furthermore, PagGIs-PagSOS2 complexes inhibited PagSOS2-regulated phosphorylation PagSOS1 absence stress, whereas these inhibitions were eliminated due degradation stress. Down-regulation by RNA interference led vigorous higher biomass transgenic plants. Taken together, results indicate that several functions conserved orthologues, they lay foundation for developing new approaches producing salt-tolerant trees sustainable on marginal lands worldwide.