Key Laboratory of Bio-Resource and Eco-Environment of the Ministry of Education, College of Life Science, Sichuan University, Chengdu, 610065, China.
J Phycol. 2022 Aug;58(4):555-567. doi: 10.1111/jpy.13250. Epub 2022 May 18.
Cell cycle studies in plants and algae are highly dependent on reliable methods for detecting cellular DNA replication. With its short growth cycle and ease of genetic transformation, Phaeodactylum tricornutum is an important model organism for the study of pennate diatoms. Here we explored two different methods to detect the cell cycle of P. tricornutum, one using SYBR-green I to via flow cytometry, and the other using EdU labeling to observe cell cycle changes under fluorescence microscopy. Both EdU labeling fluorescence microscopy and SYBR-green I staining flow cytometry accurately indicated that the cells of P. tricornutum enter the G2/M phase after 12 h of light exposure. The results indicate that SYBR Green I was an adequate detection method for nuclear DNA quantitation in cells of P. tricornutum using a flow cytometer and without RNase A treatment. In addition, EdU can be applied to P. tricornutum to reliably detect cell proliferation. Besides, Mg-ProtoIX was able to reverse the cell cycle division inhibition of P. tricornutum and allow the nuclear DNA replication to proceed normally. Taken together, the photoperiodic division time point was clearly identified, which sheds light on the regulation of cell division mechanism in P. tricornutum.
植物和藻类的细胞周期研究高度依赖于可靠的方法来检测细胞 DNA 复制。菱形藻具有较短的生长周期和易于遗传转化的特点，是研究羽纹纲硅藻的重要模式生物。在这里，我们探索了两种不同的方法来检测菱形藻的细胞周期，一种是使用 SYBR 绿 I 通过流式细胞术，另一种是使用 EdU 标记在荧光显微镜下观察细胞周期变化。EdU 标记荧光显微镜和 SYBR 绿 I 染色流式细胞术都准确地表明，菱形藻细胞在暴露于光 12 小时后进入 G2/M 期。结果表明，SYBR Green I 是一种在不使用 RNase A 处理的情况下使用流式细胞仪定量检测菱形藻细胞核 DNA 的充分检测方法。此外，EdU 可应用于菱形藻中，以可靠地检测细胞增殖。此外，Mg-ProtoIX 能够逆转菱形藻的细胞周期分裂抑制，使核 DNA 复制正常进行。综上所述，明确了光周期分裂时间点，为菱形藻细胞分裂机制的调控提供了线索。
