Department of Entomology and MOA Lab for Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China.
Department of Entomology and MOA Lab for Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing, 100193, China.
Insect Biochem Mol Biol. 2021 Apr;131:103552. doi: 10.1016/j.ibmb.2021.103552. Epub 2021 Feb 9.
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常见的现象，通过这种现象，组织可以修复受损或自然脱落的部分。在昆虫中，附肢再生发生在胚胎、幼虫和蛹期，以保证个体的生存。在黑切夜蛾 Agrotis ypsilon 中，翅膀盘在被切除后具有再生能力，但对翅膀盘再生的分子机制的理解仍然有限。在第五龄幼虫期之前，对部分或整个翅膀盘进行切除后，成虫翅膀看起来正常。在最后两个幼虫期，对左翅膀盘的切除导致相应的成虫翅膀变小。在被切除的翅膀盘中，细胞增殖减少，但在切除后两天逐渐恢复。转录组分析发现，丝裂原活化蛋白激酶（MAPK）途径中的基因被上调。通过 RNA 干扰抑制该途径中的基因表达，包括 Ras 癌基因 64B（Ras64B）、Raf1 的下游（Dsor1）和 cAMP 依赖性蛋白激酶催化亚基 3（Pka-C3），导致成虫翅膀变小，表明 MAPK 信号通路对于翅膀生长是必需的。此外，在切除后两天注射 Ras64B、Dsor 或 Pka-C3 dsRNA 仍然会减缓细胞增殖，表明 MAPK 信号通路调控的细胞增殖对于生长是必需的。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。
