Sanchez-Pulido Luis, Valencia Alfonso, Rojas Ana M
National Center for Biotechnology, Consejo Superior de Investigaciones Cientificas. C/Darwin n3, 28049, Madrid, Spain.
Trends Biochem Sci. 2007 Sep;32(9):400-6. doi: 10.1016/j.tibs.2007.08.001. Epub 2007 Aug 10.
Promyelocytic leukaemia protein nuclear bodies (PML-NBs) are nuclear structures whose function is still poorly understood. They are implicated in various biological functions, such as viral infection, cellular transformation, innate immunity and growth control, and they might be dynamic hubs sensing stress and DNA damage. Data from PML(-/-) mice suggest that PML-NBs are involved in apoptosis via caspase-independent mechanisms, probably involving p53-dependent and independent pathways. However, the recently demonstrated co-localization of caspase-2 within the PML-NB nuclear structures presents a new paradigm for nuclear cell death. Here, we show that these nuclear structures have a protein known as SP100 that could contain a caspase recruitment domain (CARD). If verified experimentally, this discovery will suggest a mechanism by which caspase-2 could be recruited into the complex and ultimately lead to apoptosis.
早幼粒细胞白血病蛋白核体（PML-NBs）是一种核结构，其功能仍知之甚少。它们参与多种生物学功能，如病毒感染、细胞转化、先天免疫和生长控制，并且可能是感知应激和DNA损伤的动态中心。来自PML（-/-）小鼠的数据表明，PML-NBs通过不依赖半胱天冬酶的机制参与细胞凋亡，可能涉及p53依赖和独立的途径。然而，最近证明的半胱天冬酶-2在PML-NB核结构中的共定位为细胞核细胞死亡提供了一种新的模式。在这里，我们表明这些核结构有一种名为SP100的蛋白质，它可能包含一个半胱天冬酶募集结构域（CARD）。如果通过实验得到证实，这一发现将提示一种机制，通过该机制半胱天冬酶-2可以被招募到复合物中并最终导致细胞凋亡。
