Interactions within Supramolecular Protein Complexes: the Proteasome Case
Bertrand Fabre, Thomas Lambour, Luc Garrigues, François Amalric, Nathalie Vigneron,
Thomas Menneteau, Alexandre Stella, Bernard Monsarrat, Benoît Van den Eynde, Odile Burlet-Schiltz,
& Marie-Pierre Bousquet-Dubouch
Molecular Systems Biology (2015) 11: 771
Proteasomes are dynamic structures and adapt to their diverse biological contexts by
changing their overall subunit composition and association with regulatory particles and interacting proteins.
This high level of proteasome diversity could reflect specialized functions of each individual proteasome form.
This paper demonstrates an approach to decipher proteasome heterogeneity through label-free
quantitative proteomics. The authors analyzed sub-complex composition by combining affinity purification and
protein abundance correlation profiling with high-resolution mass spectrometry. By correlating proteins
abundances across a large set of 24 proteasome samples immunopurified from nine different human cell lines,
they observed that the two main 20S proteasome subtypes, sP20S and iP20S, interact with a different
subset of regulators. This approach could be applied to other important large complexes.