Xu Nan, Wei Sheng-Fei, Xu Hai-Jun
State Key Laboratory of Rice Biology, Zhejiang University, Hangzhou 310058, China.
Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Zhejiang University, Hangzhou 310058, China.
Insects. 2021 May 4;12(5):413. doi: 10.3390/insects12050413.
The brown planthopper (BPH), , can develop into either short-winged (SW) or long-winged (LW) adults according to environmental conditions, and has long served as a model organism for exploring the mechanisms of wing polyphenism in insects. The transcription factor FoxO acts as a master regulator that directs the development of either SW or LW morphs, but the underlying molecular mechanism is largely unknown. Here, we microinjected SW-destined morphs with double stranded-RNA (dsRNA) targeting (ds) to change them into LW-winged morphs. In parallel, SW-destined morphs microinjected with dsRNA targeting the gene encoding green fluorescence protein (ds) served as a negative control. The forewing and hindwing buds of 5th-instar nymphs collected at 24, 36, and 48 h after eclosion (hAE) were used for RNA sequencing. We obtained a minimum of 43.4 million clean reads from forewing and hindwing buds at a single developmental time. Differentially expressed genes (DEGs) were significantly enriched in various Gene Ontology (GO) terms, including cellular process, binding, and cell part. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway analysis showed that up-regulated genes in ds-treated forewing and hindwing buds were largely associated with the cell cycle and DNA replication. Furthermore, most up-regulated genes displayed higher expression at 24-, and 36-hAE relative to 48 hAE, indicating that wing cells in LW-destined wings might actively proliferate during the first 36 h in 5th-instar nymphs. Our findings indicated that LW development in BPH was likely dependent on the duration of cell proliferation in the 5th-instar stage, which sheds light on the molecular basis of wing polymorphism in insects.
褐飞虱（BPH）可根据环境条件发育为短翅型（SW）或长翅型（LW）成虫，长期以来一直是探索昆虫翅多型性机制的模式生物。转录因子FoxO作为主要调节因子，指导SW或LW形态的发育，但其潜在的分子机制 largely unknown。在这里，我们向注定发育为SW的形态中显微注射靶向（ds）的双链RNA（dsRNA），将它们转变为LW翅型形态。同时，向注定发育为SW的形态中显微注射靶向编码绿色荧光蛋白基因（ds）的dsRNA作为阴性对照。羽化后24、36和48小时（hAE）收集的5龄若虫的前翅和后翅芽用于RNA测序。我们在单个发育时间从前翅和后翅芽中获得了至少4340万个clean reads。差异表达基因（DEGs）在各种基因本体论（GO）术语中显著富集，包括细胞过程、结合和细胞部分。京都基因与基因组百科全书（KEGG）富集途径分析表明，ds处理的前翅和后翅芽中上调的基因主要与细胞周期和DNA复制相关。此外，大多数上调基因在24-和36-hAE时的表达高于48 hAE，表明注定发育为LW的翅膀中的翅细胞在5龄若虫的前36小时可能会积极增殖。我们的研究结果表明，BPH中LW的发育可能取决于5龄期细胞增殖的持续时间，这为昆虫翅多态性的分子基础提供了线索。
