Lindsay Cory R, Morozov Viacheslav M, Ishov Alexander M
Department of Anatomy and Cell Biology & Shands Cancer Center, University of Florida College of Medicine, 1376 Mowry Road, Gainesville, FL 32610, USA.
Front Biosci. 2008 May 1;13:7132-42. doi: 10.2741/3216.
Proteins that combine PML NBs (ND10) can be divided into two groups: "transient" (that accumulate at PML NBs upon over-expression, interferon-induced up-regulation, block of proteosomal degradation, environmental stress or viral infection) and "constitutive" that co-localize with PML in the majority of cultured cells. One of the few "constitutive" components of PML NBs is the death domain-associated protein Daxx. While PML NBs are the most obvious depositories of Daxx, there are multiple alternative localization of this protein in the nucleus and cytoplasm, suggesting differential functionality of Daxx at different cellular compartments and stages of the cell cycle. The purpose of this review is to analyze Daxx spatiotemporal behavior within and outside of PML NBs and to discuss functions attributed to these localizations. We suggest that Daxx can participate in numerous cellular functions as a mediator of protein interactions, thus acting as a fine tuning instrument in highly orchestrated cellular processes; we also envision PML NBs accumulation of Daxx as an "out of action" storage depot.
结合早幼粒细胞白血病核小体（ND10）的蛋白质可分为两组：“瞬时性”（在过表达、干扰素诱导上调、蛋白酶体降解受阻、环境应激或病毒感染时在早幼粒细胞白血病核小体处积累）和“组成性”（在大多数培养细胞中与早幼粒细胞白血病蛋白共定位）。早幼粒细胞白血病核小体少数“组成性”成分之一是死亡结构域相关蛋白Daxx。虽然早幼粒细胞白血病核小体是Daxx最明显的储存部位，但该蛋白在细胞核和细胞质中有多种其他定位，提示Daxx在细胞周期的不同细胞区室和阶段具有不同功能。本综述的目的是分析Daxx在早幼粒细胞白血病核小体内外的时空行为，并讨论这些定位所赋予的功能。我们认为，Daxx可作为蛋白质相互作用的介质参与众多细胞功能，从而在高度协调的细胞过程中充当微调工具；我们还设想Daxx在早幼粒细胞白血病核小体处的积累是一个“失效”的储存库。
