Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
State Key Laboratory of Cotton Biology, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang, 455000, China.
Planta. 2022 Jan 10;255(2):34. doi: 10.1007/s00425-021-03767-1.
The SNF5-type protein BUSHY plays a role in the regulation of seed germination via the gibberellin pathway dependent on HUB1 in Arabidopsis thaliana. SWITCH/SUCROSE NONFERMENTING (SWI/SNF) complexes play diverse roles in plant development. Some components have roles in embryo development and seed maturation, however, whether the SNF5-type protein BUSHY (BSH), one of the components, plays a role in Arabidopsis seed related traits is presently unclear. In our study, we show that a loss-of-function mutation in BSH causes increased seed germination in Arabidopsis. BSH transcription was induced by the gibberellin (GA) inhibitor paclobutrazol (PAC) in the seed, and BSH regulates the expression of GA pathway genes, such as Gibberellin 3-Oxidase 1 (GA3OX1), Gibberellic Acid-Stimulated Arabidopsis 4 (GASA4), and GASA6 during seed germination. A genetic analysis showed that seed germination was distinctly improved in the bshga3ox1ga3ox2 triple mutant, indicating that BSH acts partially downstream of GA3OX1 and GA3OX2. Moreover, the regulation of seed germination by BSH in response to PAC is dependent on HUB1. These results provide new insights and clues to understand the mechanisms of phytohormones in the regulation of seed germination.
SNF5 型蛋白 BUSHY 通过依赖于拟南芥 HUB1 的赤霉素途径在种子萌发的调控中发挥作用。SWITCH/SUCROSE NONFERMENTING（SWI/SNF）复合物在植物发育中发挥着多样化的作用。一些成分在胚胎发育和种子成熟中发挥作用，然而，SNF5 型蛋白 BUSHY（BSH）作为其中的一个成分，是否在拟南芥种子相关性状中发挥作用目前尚不清楚。在我们的研究中，我们表明 bsh 功能丧失突变导致拟南芥种子萌发增加。BSH 转录在种子中被赤霉素（GA）抑制剂多效唑（PAC）诱导，BSH 调节 GA 途径基因的表达，如赤霉素 3-氧化酶 1（GA3OX1）、赤霉素刺激的拟南芥 4（GASA4）和 GASA6 在种子萌发过程中。遗传分析表明，bshga3ox1ga3ox2 三重突变体的种子萌发明显改善，表明 BSH 部分作用于 GA3OX1 和 GA3OX2 下游。此外，BSH 对 PAC 响应的种子萌发调控依赖于 HUB1。这些结果为理解植物激素在种子萌发调控中的作用机制提供了新的见解和线索。
