第二个线粒体释放的半胱天冬蛋白酶激活剂(second mitochondria-derived activator of caspase,Smac)是一种从线粒体释放的促凋亡蛋白,定位于线粒体膜间隙中。研究发现Smac的线粒体定位信号肽被切除后,Smac会从线粒体释放进入胞浆,能够...第二个线粒体释放的半胱天冬蛋白酶激活剂(second mitochondria-derived activator of caspase,Smac)是一种从线粒体释放的促凋亡蛋白,定位于线粒体膜间隙中。研究发现Smac的线粒体定位信号肽被切除后,Smac会从线粒体释放进入胞浆,能够竞争性结合凋亡抑制蛋白(inhibitors of apoptosis proteins,IAPs)或者促进IAPs的泛素化降解,抑制IAPs的表达,解除IAPs对细胞凋亡酶(caspase)的抑制作用,从而诱导细胞凋亡级联反应的发生。该文总结并综述了Smac的生物学特性、Smac调控IAPs促进细胞凋亡发生的途径、Smac调控IAPs促进肿瘤细胞、T细胞及肌细胞凋亡研究进展的相关报道,并对Smac调控IAPs促进肿瘤细胞、T细胞和肌细胞凋亡的未来研究方向进行展望,可为肿瘤的靶向治疗和肌肉的嫩化理论提供新的见解。展开更多
The destruction of proteins in proteasomes is regulated at various levels. One of the early rate-limiting steps is 'tagging' of proteins with ubiquitin, an 8 kD molecule that, when present in chains of four re...The destruction of proteins in proteasomes is regulated at various levels. One of the early rate-limiting steps is 'tagging' of proteins with ubiquitin, an 8 kD molecule that, when present in chains of four residues or more, serves as a signal recognized by proteasomal subunits. Ubiquitin is attached to target proteins by a series of enzymatic steps involving an El (ubiquitin activating enzyme), E2 (ubiquitin conjugating enzyme), and E3 (ubiquitin protein ligase). It is the last enzyme that confers target protein specificity. We have found that members of a family of RING domain containing proteins with anti- apoptotic activity, IAPs,展开更多
文摘第二个线粒体释放的半胱天冬蛋白酶激活剂(second mitochondria-derived activator of caspase,Smac)是一种从线粒体释放的促凋亡蛋白,定位于线粒体膜间隙中。研究发现Smac的线粒体定位信号肽被切除后,Smac会从线粒体释放进入胞浆,能够竞争性结合凋亡抑制蛋白(inhibitors of apoptosis proteins,IAPs)或者促进IAPs的泛素化降解,抑制IAPs的表达,解除IAPs对细胞凋亡酶(caspase)的抑制作用,从而诱导细胞凋亡级联反应的发生。该文总结并综述了Smac的生物学特性、Smac调控IAPs促进细胞凋亡发生的途径、Smac调控IAPs促进肿瘤细胞、T细胞及肌细胞凋亡研究进展的相关报道,并对Smac调控IAPs促进肿瘤细胞、T细胞和肌细胞凋亡的未来研究方向进行展望,可为肿瘤的靶向治疗和肌肉的嫩化理论提供新的见解。
文摘The destruction of proteins in proteasomes is regulated at various levels. One of the early rate-limiting steps is 'tagging' of proteins with ubiquitin, an 8 kD molecule that, when present in chains of four residues or more, serves as a signal recognized by proteasomal subunits. Ubiquitin is attached to target proteins by a series of enzymatic steps involving an El (ubiquitin activating enzyme), E2 (ubiquitin conjugating enzyme), and E3 (ubiquitin protein ligase). It is the last enzyme that confers target protein specificity. We have found that members of a family of RING domain containing proteins with anti- apoptotic activity, IAPs,
