Department of Environmental Studies, Laboratory of Bioresources & Environmental Biotechnology, University of Delhi, Delhi, -110 007, India.
Appl Biochem Biotechnol. 2012 Mar;166(6):1552-61. doi: 10.1007/s12010-012-9550-x. Epub 2012 Jan 20.
Apoptotic cell death is a fundamental process in the development and physiological homeostasis of multicellular organisms. It is associated with control of cell numbers in tissues and organs during development, with cell turnover, and with response to infection. Molecules that trigger this process in continuously proliferating cancer cells can be used as chemotherapeutic agents. Ribosome inactivating proteins (RIPs) that inhibit translation in a cell by depurinating (N-glycosidase activity) the 28S rRNA are known to serve as apoptosis inducers. However, the role of depurination activity of the RIPs in apoptosis induction is still controversial. Presently, there are three different hypotheses which propose that depurination is: (1) essential, (2) essential but not the sole factor, or (3) not essential for apoptosis induction. This article reviews various experimental outcomes on the importance of N-glycosidase activity of RIPs in the induction of apoptosis.
细胞凋亡是多细胞生物发育和生理稳态的基本过程。它与组织和器官在发育过程中的细胞数量控制、细胞更新以及对感染的反应有关。能够触发持续增殖的癌细胞发生这种过程的分子可用作化疗药物。核糖体失活蛋白（RIP）通过脱嘌呤（N-糖苷酶活性）28S rRNA 来抑制细胞中的翻译，已知其可作为凋亡诱导剂。然而，RIP 的脱嘌呤活性在凋亡诱导中的作用仍然存在争议。目前，有三种不同的假说提出脱嘌呤作用：（1）必需的，（2）必需但不是唯一因素，或（3）对凋亡诱导不是必需的。本文综述了关于 RIP 的 N-糖苷酶活性在诱导凋亡中的重要性的各种实验结果。
