State Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China; National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya, Hainan, China.
State Key Laboratory of Cotton Bio-breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, China.
Mol Plant. 2024 Oct 7;17(10):1539-1557. doi: 10.1016/j.molp.2024.08.007. Epub 2024 Aug 22.
Optimal plant height is crucial in modern agriculture, influencing lodging resistance and facilitating mechanized crop production. Upland cotton (Gossypium hirsutum) is the most important fiber crop globally; however, the genetic basis underlying plant height remains largely unexplored. In this study, we conducted a genome-wide association study to identify a major locus controlling plant height (PH1) in upland cotton. This locus encodes gibberellin 2-oxidase 1A (GhPH1) and features a 1133-bp structural variation (PAV) located approximately 16 kb upstream. The presence or absence of PAV influences the expression of GhPH1, thereby affecting plant height. Further analysis revealed that a gibberellin-regulating transcription factor (GhGARF) recognizes and binds to a specific CATTTG motif in both the GhPH1 promoter and PAV. This interaction downregulates GhPH1, indicating that PAV functions as a distant upstream silencer. Intriguingly, we found that DWARF53 (D53), a key repressor of the strigolactone (SL) signaling pathway, directly interacts with GhGARF to inhibit its binding to targets. Moreover, we identified a previously unrecognized gibberellin-SL crosstalk mechanism mediated by the GhD53-GhGARF-GhPH1/PAV module, which is crucial for regulating plant height in upland cotton. These findings shed light on the genetic basis and gene interaction network underlying plant height, providing valuable insights for the development of semi-dwarf cotton varieties through precise modulation of GhPH1 expression.
理想的株高在现代农业中至关重要，它影响抗倒伏能力，并便于机械化作物生产。陆地棉（Gossypium hirsutum）是全球最重要的纤维作物；然而，株高的遗传基础在很大程度上仍未被探索。在本研究中，我们进行了全基因组关联研究，以鉴定控制陆地棉株高（PH1）的主要位点。该位点编码赤霉素 2-氧化酶 1A（GhPH1），并具有约 16 kb 上游的 1133bp 结构变异（PAV）。PAV 的存在或不存在会影响 GhPH1 的表达，从而影响株高。进一步的分析表明，赤霉素调节转录因子（GhGARF）识别并结合 GhPH1 启动子和 PAV 中的特定 CATTTG 基序。这种相互作用下调了 GhPH1，表明 PAV 作为一个远距离的上游沉默子发挥作用。有趣的是，我们发现矮化 53（D53），一个独脚金内酯（SL）信号通路的关键抑制剂，直接与 GhGARF 相互作用，抑制其与靶标的结合。此外，我们确定了一个以前未被识别的赤霉素-SL 串扰机制，该机制由 GhD53-GhGARF-GhPH1/PAV 模块介导，对于调节陆地棉的株高至关重要。这些发现揭示了株高的遗传基础和基因互作网络，为通过精确调节 GhPH1 的表达来开发半矮化棉花品种提供了有价值的见解。
