›› 2009, Vol. 52 ›› Issue (6): 604-609.

• 研究论文 • 上一篇    下一篇



  • 出版日期:2009-06-20 发布日期:2009-06-20
  • 通讯作者: 赵林川

Effects of different incubation on expression of catalase gene in the bivoltine silkworm (Bombyx mori)

  • Online:2009-06-20 Published:2009-06-20

摘要: 25℃明催青和15℃暗催青分别诱导二化性家蚕Bombyx mori 产滞育性卵和非滞育性卵。此前我们的研究表明, 上述催青处理的二化性家蚕H2O2水平存在显著差异。过氧化氢酶(catalase, CAT)是昆虫清除H2O2的关键酶。为了进一步明确家蚕滞育过程中H2O2代谢的调控机制, 用RT-PCR测定了上述两种催青处理对二化性家蚕CAT基因表达的影响。结果表明:25℃明催青显著提高了滞育诱导和决定阶段的CAT mRNA 水平和CAT活性。滞育性卵的CAT mRNA水平在产后24 h形成峰值, 在72 h后消失; CAT活性在96 h前上升, 120 h后保持于低水平。非滞育性卵的CAT mRNA水平和CAT活性都随着胚胎发育而上升。可见, 25℃明催青诱导二化性家蚕子代滞育可能是通过影响CAT基因表达来调节H2O2水平。

关键词: 二化性家蚕, 滞育, 催青, 过氧化氢酶, 基因表达

Abstract: When eggs of the bivoltine silkworm, Bombyx mori, are incubated at 25℃ under illumination and 15℃ under darkness, diapause and nondiapause eggs are laid, respectively. Our previous studies revealed that there was a significant difference in the level of hydrogen peroxide (H2O2) between the two incubation treatments in the bivoltine silkworm. Catalase is the key enzyme to scavenge H2O2 in insects. In this study the expression of catalase gene of the silkworm with two above incubation treatments was determined with RT-PCR to investigate the regulatory mechanism of H2O2 metabolism. The results indicated that compared to the 15℃ under darkness incubation, enhanced mRNA level and activity of catalase in the 25℃ under illumination incubation were observed at the induction and decision stage of diapause in maternal generation. In diapause eggs, catalase mRNA peaked at 24 h but disappeared at 72 h and thereafter while its activity increased until 96 h but kept at a low level and varied slightly 120 h after oviposition. In nondiapause eggs, however, both mRNA level and activity of catalase increased coinciding with embryogenesis. The results suggest that the induction of progeny diapause in the bivoltine B. mori by the 25℃ under illumination incubation may regulate the H2O2 level via affecting expression of catalase gene.

Key words: Bivoltine Bombyx mori, diapause, incubation, catalase, gene expression