Sang Na, Liu Hui, Ma Bin, Huang Xianzhong, Zhuo Lu, Sun Yuqiang
The Key Laboratory of Oasis Eco-Agriculture, College of Agriculture, Shihezi University, Shihezi, 832000, China.
Special Plant Genomics Laboratory, College of Life Sciences, Shihezi University, Shihezi, 832000, China.
BMC Plant Biol. 2021 Mar 31;21(1):162. doi: 10.1186/s12870-021-02923-9.
In plants, 14-3-3 proteins, also called GENERAL REGULATORY FACTORs (GRFs), encoded by a large multigene family, are involved in protein-protein interactions and play crucial roles in various physiological processes. No genome-wide analysis of the GRF gene family has been performed in cotton, and their functions in flowering are largely unknown.
In this study, 17, 17, 31, and 17 GRF genes were identified in Gossypium herbaceum, G. arboreum, G. hirsutum, and G. raimondii, respectively, by genome-wide analyses and were designated as GheGRFs, GaGRFs, GhGRFs, and GrGRFs, respectively. A phylogenetic analysis revealed that these proteins were divided into ε and non-ε groups. Gene structural, motif composition, synteny, and duplicated gene analyses of the identified GRF genes provided insights into the evolution of this family in cotton. GhGRF genes exhibited diverse expression patterns in different tissues. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that the GhGRFs interacted with the cotton FLOWERING LOCUS T homologue GhFT in the cytoplasm and nucleus, while they interacted with the basic leucine zipper transcription factor GhFD only in the nucleus. Virus-induced gene silencing in G. hirsutum and transgenic studies in Arabidopsis demonstrated that GhGRF3/6/9/15 repressed flowering and that GhGRF14 promoted flowering.
Here, 82 GRF genes were identified in cotton, and their gene and protein features, classification, evolution, and expression patterns were comprehensively and systematically investigated. The GhGRF3/6/9/15 interacted with GhFT and GhFD to form florigen activation complexs that inhibited flowering. However, GhGRF14 interacted with GhFT and GhFD to form florigen activation complex that promoted flowering. The results provide a foundation for further studies on the regulatory mechanisms of flowering.
在植物中，14-3-3蛋白也被称为通用调控因子（GRF），由一个大型多基因家族编码，参与蛋白质-蛋白质相互作用，并在各种生理过程中发挥关键作用。尚未在棉花中对GRF基因家族进行全基因组分析，其在开花过程中的功能也 largely未知。
在本研究中，通过全基因组分析，分别在草棉、亚洲棉、陆地棉和雷蒙德氏棉中鉴定出17、17、31和17个GRF基因，分别命名为GheGRFs、GaGRFs、GhGRFs和GrGRFs。系统发育分析表明，这些蛋白质分为ε组和非ε组。对鉴定出的GRF基因进行基因结构、基序组成、共线性和重复基因分析，为该家族在棉花中的进化提供了见解。GhGRF基因在不同组织中表现出多样的表达模式。酵母双杂交和双分子荧光互补分析表明，GhGRFs在细胞质和细胞核中与棉花开花位点T同源物GhFT相互作用，而它们仅在细胞核中与碱性亮氨酸拉链转录因子GhFD相互作用。在陆地棉中进行的病毒诱导基因沉默和在拟南芥中进行的转基因研究表明，GhGRF3/6/9/15抑制开花，而GhGRF14促进开花。
本研究在棉花中鉴定出82个GRF基因，并对其基因和蛋白质特征、分类、进化和表达模式进行了全面系统的研究。GhGRF3/6/9/15与GhFT和GhFD相互作用形成抑制开花的成花素激活复合物。然而，GhGRF14与GhFT和GhFD相互作用形成促进开花的成花素激活复合物。这些结果为进一步研究开花调控机制奠定了基础。
