Lin Chih-Chien, Hsu John T-A, Huang Kai-Ling, Tang Hung-Kuan, Shu Chih-Wen, Lai Yiu-Kay
Institute of Biotechnology and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.
Biotechnol Appl Biochem. 2007 Sep;48(Pt 1):11-9. doi: 10.1042/BA20070044.
Sf-Caspase-1 [Spodoptera frugiperda (fall armyworm) caspase-1] is the most studied effector caspase of Lepidoptera and its activation may lead cells to apoptosis (programmed cell death) when under UV irradiation or baculovirus infection. In the present study, we repressed the expression of Sf-caspase-1 in Sf9 (S. frugiperda 9) cells using constitutive RNA interference, and evaluated the effects of stress responses and the production of proteins in recombinant baculovirus-infected cells. The Sf-caspase-1-repressed stable cells, Sf9/pIBdsCasp-1 and Sf9/pIBdsCasp-2, showed a significant increase in resistance to UV- and baculovirus-induced apoptosis. These cells produced higher levels of both intracellular (luciferase) and extracellular [SEAP (secreted alkaline phosphatase)] recombinant proteins than the parental cells when infected with recombinant baculovirus. Thus Sf-caspase-1-repressed stable cells have a greater ability to adapt to various culture conditions, and also to provide the benefits of high-level protein production.
草地贪夜蛾半胱天冬酶-1（Sf-Caspase-1）[草地贪夜蛾（秋粘虫）半胱天冬酶-1]是鳞翅目研究最多的效应半胱天冬酶，在紫外线照射或杆状病毒感染时，其激活可能导致细胞凋亡（程序性细胞死亡）。在本研究中，我们使用组成型RNA干扰抑制了草地贪夜蛾细胞系Sf9（草地贪夜蛾9）中Sf-caspase-1的表达，并评估了应激反应的影响以及重组杆状病毒感染细胞中蛋白质的产生。抑制Sf-caspase-1的稳定细胞系Sf9/pIBdsCasp-1和Sf9/pIBdsCasp-2对紫外线和杆状病毒诱导的凋亡具有显著增强的抗性。当用重组杆状病毒感染时，这些细胞产生的细胞内（荧光素酶）和细胞外[分泌型碱性磷酸酶（SEAP）]重组蛋白水平均高于亲本细胞。因此，抑制Sf-caspase-1的稳定细胞具有更强的适应各种培养条件的能力，同时也具有高水平蛋白质生产的优势。
