Proteomic analysis of the 20S proteasome (PSMA3)-interacting proteins reveals a functional link between the proteasome and mRNA metabolism
Proteomic analysis of the 20S proteasome (PSMA3)-interacting proteins reveals a functional link between the proteasome and mRNA metabolism
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DOI：
10.1016/j.bbrc.2011.10.126
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发表时间：
2011-12-16
影响因子：
3.1
通讯作者：
Barlev, Nickolai A.
中科院分区：
文献类型：
--
作者：
Fedorova, Olga A.;Moiseeva, Tatiana N.;Barlev, Nickolai A.
26 S蛋白酶体是一种大的多亚基蛋白复合物，其在细胞中发挥蛋白质的特异性降解。26 S蛋白酶体由20 S蛋白水解颗粒和19 S调节剂组成。为了被蛋白酶体降解，大多数蛋白质必须经历多聚泛素化的翻译后修饰。然而，许多蛋白质也可以通过蛋白酶体通过泛素非依赖性途径降解。这种降解主要通过底物蛋白与20 S复合物的PSMA 3（α 7）亚基结合来实现。然而，与PSMA 3相互作用的蛋白质的系统分析尚未进行。在这份报告中，我们描述了与PSMA 3在细胞质和细胞核中的蛋白质的鉴定。二维凝胶电泳（2D-GE）和串联质谱的组合揭示了大量的PSMA 3结合蛋白，参与mRNA代谢的各个方面，包括剪接。体外生物化学研究证实了PSMA 3和剪接因子之间的相互作用。此外，我们发现20 S蛋白酶体参与SMN 2（运动神经元存活基因2）基因的体外剪接调控，其产物控制神经元的凋亡。(C)2011 Elsevier Inc. All rights reserved.
The 26S proteasome is a large multi-subunit protein complex that exerts specific degradation of proteins in the cell. The 26S proteasome consists of the 20S proteolytic particle and the 19S regulator. In order to be targeted for proteasomal degradation most of the proteins must undergo the post-translational modification of poly-ubiquitination. However, a number of proteins can also be degraded by the proteasome via a ubiquitin-independent pathway. Such degradation is exercised largely through the binding of substrate proteins to the PSMA3 (alpha 7) subunit of the 20S complex. However, a systematic analysis of proteins interacting with PSMA3 has not yet been carried out. In this report, we describe the identification of proteins associated with PSMA3 both in the cytoplasm and nucleus. A combination of two-dimensional gel electrophoresis (2D-GE) and tandem mass-spectrometry revealed a large number of PSMA3-bound proteins that are involved in various aspects of mRNA metabolism, including splicing. In vitro biochemical studies confirmed the interactions between PSMA3 and splicing factors. Moreover, we show that 20S proteasome is involved in the regulation of splicing in vitro of SMN2 (survival motor neuron 2) gene, whose product controls apoptosis of neurons. (C) 2011 Elsevier Inc. All rights reserved.