Deciphering preferential interactions within supramolecular protein complexes: the proteasome case

作者：Fabre Bertrand; Lambour Thomas; Garrigues Luc; Amalric Francois; Vigneron Nathalie; Menneteau Thomas; Stella Alexandre; Monsarrat Bernard; Van den Eynde Benoit; Burlet Schiltz Odile^*; Bousquet Dubouch Marie Pierre

来源：Molecular Systems Biology, 2015, 11(1): 771-771.

DOI：10.15252/msb.20145497

• affinity purification
• correlation profiling
• label-free quantitative proteomics
• mass spectrometry

In eukaryotic cells, intracellular protein breakdown is mainly performed by the ubiquitin-proteasome system. Proteasomes are supramolecular protein complexes formed by the association of multiple sub-complexes and interacting proteins. Therefore, they exhibit a very high heterogeneity whose function is still not well understood. Here, using a newly developed method based on the combination of affinity purification and protein correlation profiling associated with high-resolution mass spectrometry, we comprehensively characterized proteasome heterogeneity and identified previously unknown preferential associations within proteasome sub-complexes. In particular, we showed for the first time that the two main proteasome subtypes, standard proteasome and immunoproteasome, interact with a different subset of important regulators. This trend was observed in very diverse human cell types and was confirmed by changing the relative proportions of both 20S proteasome forms using interferon-. The new method developed here constitutes an innovative and powerful strategy that could be broadly applied for unraveling the dynamic and heterogeneous nature of other biologically relevant supramolecular protein complexes.

• 出版日期2015-1