Laboratório de Química e Função de Proteínas e Peptídeos, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, Brazil.
Laboratório Integrado de Ciências Morfofuncionais, Núcleo em Ecologia e Desenvolvimento SócioAmbiental de Macaé (NUPEM), Macaé, Brazil.
Sci Rep. 2019 Jul 3;9(1):9601. doi: 10.1038/s41598-019-45898-2.
Gibberellins (GA) are key positive regulators of seed germination. Although the GA effects on seed germination have been studied in a number of species, little is known about the transcriptional reprogramming modulated by GA during this phase in species other than Arabidopsis thaliana. Here we report the transcriptome analysis of soybean embryonic axes during germination in the presence of paclobutrazol (PBZ), a GA biosynthesis inhibitor. We found a number of differentially expressed cell wall metabolism genes, supporting their roles in cell expansion during germination. Several genes involved in the biosynthesis and signaling of other phytohormones were also modulated, indicating an intensive hormonal crosstalk at the embryonic axis. We have also found 26 photosynthesis genes that are up-regulated by PBZ at 24 hours after imbibition (HAI) and down-regulated at 36 HAI, which led us to suggest that this is part of a strategy to implement an autotrophic growth program in the absence of GA-driven mobilization of reserves. Finally, 30 transcription factors (mostly from the MYB, bHLH, and bZIP families) were down-regulated by PBZ and are likely downstream GA targets that will drive transcriptional changes during germination.
赤霉素（GA）是种子萌发的关键正调控因子。虽然 GA 对种子萌发的影响在许多物种中都有研究，但在拟南芥以外的物种中，GA 在这个阶段调控的转录重编程知之甚少。在这里，我们报告了赤霉素生物合成抑制剂多效唑（PBZ）存在下大豆胚轴在萌发过程中的转录组分析。我们发现了许多差异表达的细胞壁代谢基因，支持它们在萌发过程中细胞扩张的作用。其他植物激素的生物合成和信号转导也有几个基因被调控，表明在胚胎轴上存在强烈的激素串扰。我们还发现了 26 个光合作用基因，它们在吸水 24 小时后（HAI）被 PBZ 上调，而在 36 HAI 时下调，这使我们推测这是在没有 GA 驱动储备动员的情况下实施自养生长计划的一部分策略。最后，30 个转录因子（主要来自 MYB、bHLH 和 bZIP 家族）被 PBZ 下调，可能是 GA 下游的靶标，将在萌发过程中驱动转录变化。
