HtrA2 유전자가 결손된 mouse embryonic fibroblast 세포주의 형태학적 특징 및 세포사멸 자극에 대한 감수성 조사

High-temperature requirement A2 (HtrA2) has been known as a human homologue of bacterial HtrA that has a molecular chaperone function. HtrA2 is mitochondrial serine protease that plays a significant role in regulating the apoptosis; however, the physiological function of HtrA2 still remains elusive. To establish experimental system for the investigation of new insights into the function of HtrA2 in mammalian cells, we first obtained HtrA2 +/+ and HtrA2 -/- MEF cells lines and identified those cells based on the expression pattern and subcellular localization of HtrA2, using immunoblot and biochemical assays. Additionally, we observed that the morphological characteristics of HtrA2 -/- MEF cells are different form those of HtrA 2+/+ MEF cells, showing a rounded shape instead of a typical fibroblast-like shape. Growth rate of HtrA2 -/- MEF cells was also 1.4-fold higher than that of HtrA2 +/+ MEF cells at 36 hours. Furthermore, we verified both MEF cell lines induced caspsase-dependent cell death in response to apoptotic stimuli such as heat shock, staurosporine, and rotenone. The relationship between HtrA2 and heat shock-induced cell death is the first demonstration of the research field of HtrA2. Our study suggests that those MEF cell lines are suitable reagents to further investigate the molecular mechanism by which HtrA2 regulates the balance between cell death and survival.