Rice is an essential but highly stress-susceptible crop, whose root system plays an important role in plant development and stress adaptation. The rice root system architecture is controlled by gene regulatory networks involving different phytohormones including auxin, jasmonate, and gibberellin. Gibberellin is generally known as a molecular clock that interacts with different pathways to regulate root meristem development. The exogenous treatment of rice plantlets with Gibberellin reduced the number of crown roots, whilst the exogenous jasmonic acid treatment enhanced them by involving a Germin-like protein OsGER4. Due to those opposite effects, this study aims to investigate the effect of Gibberellin on crown root development in the rice mutant of the plasmodesmal Germin-like protein OsGER4. Under exogenous gibberellin treatment, the number of crown roots significantly increased in osger4 mutant lines and decreased in the OsGER4 overexpressed lines. GUS staining showed that OsGER4 was strongly expressed in rice root systems, particularly crown and lateral roots under GA3 application. Specifically, OsGER4 was strongly expressed from the exodermis, epidermis, sclerenchyma to the endodermis layers of the crown root, along the vascular bundle and throughout LR primordia. The plasmodesmal protein OsGER4 is suggested to be involved in crown root development by maintaining hormone homeostasis, including Gibberillin.

水稻是一种重要但高度敏感的作物，其根系在植物发育和逆境适应中发挥着重要作用。水稻根系结构由涉及不同植物激素（包括生长素、茉莉酸和赤霉素）的基因调控网络控制。赤霉素通常被称为分子钟，它与不同的途径相互作用来调节根分生组织的发育。用赤霉素对水稻幼苗进行外源处理减少了冠根的数量，而外源茉莉酸处理则通过涉及胚芽样蛋白 OsGER4 来增强冠根的数量。由于这些相反的作用，本研究旨在研究赤霉素对胞间连丝胚芽样蛋白 OsGER4 水稻突变体冠根发育的影响。在外源赤霉素处理下， osger4突变株系的冠根数量显着增加，而OsGER4过表达株系的冠根数量显着减少。GUS染色显示OsGER4在GA3施用下的水稻根系中强烈表达，特别是冠根和侧根。具体而言，OsGER4从冠根的外皮层、表皮、厚壁组织到内皮层、沿着维管束和整个LR原基强烈表达。胞间连丝蛋白 OsGER4 被认为通过维持激素稳态（包括赤霉素）参与冠根发育。