Activity-based near-infrared fluorescent probe for LMP7: a chemical proteomics tool for the immunoproteasome in living cells.
Activity-based near-infrared fluorescent probe for LMP7: a chemical proteomics tool for the immunoproteasome in living cells.
复制标题
LMP7 基于活性的近红外荧光探针：一种用于活细胞中免疫蛋白酶体的化学蛋白质组学工具。
DOI：
10.1002/cbic.201200307
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Kim,Kyung-Bo
中科院分区：
文献类型：
--
作者：
Sharma,LalitKumar;Lee,Na-Ra;Jang,EunRyoung;Lei,Beilei;Zhan,Chang-Guo;Lee,Wooin;Kim,Kyung-Bo
组成型蛋白酶体是一种多蛋白酶复合体，在真核细胞中广泛表达，通过泛素介导的蛋白质降解在调节细胞内蛋白质稳态中起重要作用。[1-3]哺乳动物细胞也可以表达蛋白酶体的另一种形式，称为免疫蛋白酶体。[4]免疫蛋白酶体在造血来源的细胞中表达，但也可以在暴露于细胞因子如干扰素-γ（IFN-γ）或肿瘤坏死因子-α（TNF-α）后在其他类型的细胞中诱导。暴露于这些刺激诱导催化亚基LMP 2（β 1 i）、MECL 1（β 2 i）和LMP 7（β5i）的合成，其分别取代它们的组成性对应物Y（β1）、Z（β2）和X（β5）以形成免疫蛋白酶体。[5]免疫蛋白酶体的主要功能被认为是促进适应性免疫应答，但最近的研究也表明免疫蛋白酶体在其他细胞过程中起重要作用[6-8]以及某些病理状态，如癌症，神经退行性疾病和自身免疫性疾病。[4，9-13]尽管最近的研究表明免疫蛋白酶体在正常和疾病状态下的不同作用，但其功能仍然知之甚少，这在很大程度上是由于缺乏合适的分子探针。在过去的十年中，针对功能活性蛋白的化学探针为蛋白质功能研究提供了很好的工具。[14-17]对于蛋白酶体生物学，这种类型的探针可能特别有用，因为细胞中有两种形式的β亚基：无催化活性的未成熟（含前肽）和活性成熟形式。[18]未成熟的β亚基仅在完全组装的蛋白酶体复合物中经历成熟。[18]因此，含有活性位点靶向药效团（如乙烯砜[19]或环氧酮官能团[20]）的蛋白酶体抑制剂可以作为基于活性的探针，仅靶向完全组装的蛋白酶体中的催化活性β亚基。这些药效团的使用导致了第一代基于活性的靶向蛋白酶体的荧光探针的设计，这被证明是有用的功能研究或抑制剂筛选。[21-23]然而，由于高度的原生序列和结构
The constitutive proteasome is a multiprotease complex expressed in all eukaryotic cells and plays an important role in regulating intracellular protein homeostasis via ubiquitinmediated degradation of proteins.[1–3] Mammalian cells can also express an alternative form of the proteasome called as the immunoproteasome.[4] The immunoproteasome is expressed in cells of hematopoietic origin but can also be induced in other types of cells upon exposure to cytokines such as interferon-γ (IFN-γ) or tumor necrosis factor-α (TNF-α). Exposure to these stimuli induces the synthesis of catalytic subunits LMP2 (β1i), MECL1 (β2i) and LMP7 (β5i), which replace their constitutive counterparts Y (β1), Z (β2) and X (β5), respectively, to form the immunoproteasome.[5] The primary function of the immunoproteasome is thought to be the promotion of adaptive immune responses, but recent studies also show that the immunoproteasome plays an important role in other cellular processes [6–8] as well as certain pathological states such as cancer, neurodegenerative and autoimmune diseases.[4, 9–13] Despite recent studies indicating the distinct role of the immunoproteasome in normal and disease states, its functions remain poorly understood, in large part due to the lack of appropriate molecular probes.Over the past decade, chemical probes targeting functionally active proteins have provided great tools for protein functional study.[14–17] For proteasome biology, this type of probe can be particularly useful, since there are two forms of β subunits in cells: catalytically inactive immature (propeptide containing) and active mature forms.[18] The immature β subunits undergo maturation only in the fully assembled proteasome complex.[18] Therefore, proteasome inhibitors which contain active-site-targeting pharmacophores, such as the vinyl sulfone [19] or epoxyketone functional groups,[20] can function as activity-based probes, targeting only the catalytically active β subunits in the fully assembled proteasome. The use of these pharmacophores led to the design of the first generation activity-based fluorescent probes targeting proteasomes, which proved to be useful in functional studies or for inhibitor screening.[21–23] However, due to a high degree of primary sequence and structural