Regeneration is a common phenomenon in various organisms by which tissues restore the damaged or naturally detached parts. In insects, appendage regeneration takes place during the embryonic, larval and pupal stages for individual survival. The wing disc of black cutworm Agrotis ypsilon has the capacity of regeneration after ablation, but understanding of molecular mechanisms in wing disc regeneration is still limited. After ablation of partial or whole wing discs before the fifth instar larval stage, the adult wings appeared to be normal. In the last two larval stages, ablation of the left wing disc led to smaller corresponding adult wing. Cell proliferation was reduced in the ablated wing disc but was gradually recovered two days post ablation. Transcriptome analysis found that genes in the mitogen-activated protein kinase (MAPK) pathway were upregulated. Repression of gene expression in this pathway, including Ras oncogene at 64B (Ras64B), Downstream of raf1 (Dsor1), and cAMP-dependent protein kinase catalytic subunit 3 (Pka-C3) by RNA interference after ablation, led to diminishment of both adult wings, suggesting that the MAPK signaling is essential for wing growth. Additionally, cell proliferation was still decelerated by injecting Ras64B, Dsor, or Pka-C3 dsRNA two days after ablation, indicating that the MAPK signaling-regulated cell proliferation is essential for growth. These results provide molecular clues to the regulation of cell proliferation during regeneration in lepidopteran insects.

再生是各种生物体中的常见现象，组织通过再生来恢复受损或自然分离的部分。在昆虫中，附属物再生发生在胚胎、幼虫和蛹阶段，以保证个体的生存。黑地老虎Agrotis ypsilon的翼盘具有消融后再生的能力，但对翼盘再生的分子机制的了解仍然有限。在第五龄幼虫阶段之前部分或整个翼盘消融后，成虫翅膀看起来是正常的。在最后两个幼虫阶段，左翼盘的消融导致相应的成虫翅膀变小。消融的翼盘中的细胞增殖减少，但在消融后两天逐渐恢复。转录组分析发现丝裂原活化蛋白激酶 (MAPK) 通路中的基因被上调。抑制该途径中的基因表达，包括64B 处的 Ras 致癌基因( Ras64B )、raf1 的下游( Dsor1 ) 和cAMP 依赖性蛋白激酶催化亚基 3 ( Pka-C3 ) 在消融后通过 RNA 干扰导致两个成年翅膀的减少，这表明 MAPK 信号传导对于翅膀的生长是必不可少的。此外，在消融两天后注射Ras64B、Dsor或Pka-C3 dsRNA仍会减慢细胞增殖，表明 MAPK 信号调节的细胞增殖对生长至关重要。这些结果为鳞翅目昆虫再生过程中细胞增殖的调控提供了分子线索。