Department of Plant Pathology and Institute of Plant Breeding, Genetics, and Genomics, University of Georgia, Athens, GA 30602, U.S.A.
Mol Plant Microbe Interact. 2024 Aug;37(8):611-618. doi: 10.1094/MPMI-04-24-0042-TA. Epub 2024 Aug 23.
Cyst nematodes co-opt plant developmental programs for the establishment of a permanent feeding site called a syncytium in plant roots. In recent years, the role of plant developmental genes in syncytium formation has gained much attention. One main obstacle in studying the function of development-related genes in syncytium formation is that mutation or ectopic expression of such genes can cause pleiotropic phenotypes, making it difficult to interpret nematode-related phenotypes or, in some cases, impossible to carry out infection assays due to aberrant root development. Here, we tested three commonly used inducible gene expression systems for their application in beet cyst nematode infection assays of the model plant . We found that even a low amount of ethanol diminished nematode development, deeming the ethanol-based system unsuitable for use in cyst nematode infection assays, whereas treatment with estradiol or dexamethasone did not negatively affect cyst nematode viability. Dose and time course responses showed that in both systems, a relatively low dose of inducer (1 μM) is sufficient to induce high transgene expression within 24 h of treatment. Transgene expression peaked at 3 to 5 days post-induction and began to decline thereafter, providing a perfect window for inducible transgenes to interfere with syncytium establishment while minimizing any adverse effects on root development. These results indicate that both estradiol- and dexamethasone-based inducible gene expression systems are suitable for cyst nematode infection assays. The employment of such systems provides a powerful tool to investigate the function of essential plant developmental genes in syncytium formation. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
胞囊线虫通过植物发育程序来建立一个称为合胞体的永久性取食部位，这种合胞体存在于植物根部。近年来，植物发育基因在合胞体形成中的作用引起了广泛关注。在研究与发育相关的基因在合胞体形成中的功能时，主要障碍之一是这些基因的突变或异位表达会导致多效表型，从而难以解释与线虫相关的表型，或者在某些情况下，由于根发育异常，无法进行感染测定。在这里，我们测试了三种常用的诱导型基因表达系统，以评估它们在模式植物上的甜菜胞囊线虫感染测定中的应用。我们发现，即使是少量的乙醇也会降低线虫的发育，这使得乙醇基系统不适合用于胞囊线虫感染测定，而用雌二醇或地塞米松处理不会对胞囊线虫的活力产生负面影响。剂量和时间进程反应表明，在这两种系统中，相对低剂量的诱导剂（1 μM）足以在处理后 24 小时内诱导高转基因表达。转基因表达在诱导后 3 至 5 天达到峰值，此后开始下降，为诱导型转基因干扰合胞体建立提供了一个完美的窗口，同时最大限度地减少了对根发育的任何不利影响。这些结果表明，雌二醇和地塞米松诱导型基因表达系统均适用于胞囊线虫感染测定。这些系统的应用为研究合胞体形成中必需的植物发育基因的功能提供了一个强大的工具。
