TY - JOUR
T1 - Immuno- and constitutive proteasome crystal structures reveal differences in substrate and inhibitor specificity
AU - Huber, Eva M.
AU - Basler, Michael
AU - Schwab, Ricarda
AU - Heinemeyer, Wolfgang
AU - Kirk, Christopher J.
AU - Groettrup, Marcus
AU - Groll, Michael
N1 - Funding Information:
This work is dedicated to Professor Robert Huber on the occasion of his 75th birthday. We are grateful to B. Potts for fruitful discussions on the manuscript and to R. Huber for sharing his knowledge in the proteasome field with us. G. Werner, U. Beck, and the personnel of the animal research facility of Constance University are acknowledged for experimental support. We thank Richard Feicht for the purification of yCPs. The staff of the beamlines X06SA and X06DA at the Paul Scherrer Institute, SLS, Villigen, Switzerland, especially Takashi Tomizaki, is acknowledged for assistance during data collection. This work was supported by the Deutsche Forschungsgemeinschaft SFB595/TP A11 (M. Groll), BMBF-ProNET-T3 project To-03 (M. Groll), the Swiss National Fonds grant 31003A_138451 (M. Groettrup), and DFG grant 1517/12-1 (M. Groettrup, M.B.). R.S. is supported by the Graduate School of Chemical Biology at Constance University. M. Groll and M. Groettrup designed experiments. M.B. and R.S. purified cCPs and iCPs. E.M.H. performed activity tests and crystallographic experiments. W.H. and E.M.H. performed yeast genetics. C.J.K. provided PR-957 and edited the manuscript. E.M.H. and M. Groll collected and analyzed crystallographic data and wrote the manuscript. C.J.K. is an employee and stock holder of Onyx Pharmaceuticals.
PY - 2012/2/17
Y1 - 2012/2/17
N2 - Constitutive proteasomes and immunoproteasomes shape the peptide repertoire presented by major histocompatibility complex class I (MHC-I) molecules by harboring different sets of catalytically active subunits. Here, we present the crystal structures of constitutive proteasomes and immunoproteasomes from mouse in the presence and absence of the epoxyketone inhibitor PR-957 (ONX 0914) at 2.9 resolution. Based on our X-ray data, we propose a unique catalytic feature for the immunoproteasome subunit β5i/LMP7. Comparison of ligand-free and ligand-bound proteasomes reveals conformational changes in the S1 pocket of β5c/X but not β5i, thereby explaining the selectivity of PR-957 for β5i. Time-resolved structures of yeast proteasome:PR-957 complexes indicate that ligand docking to the active site occurs only via the reactive head group and the P1 side chain. Together, our results support structure-guided design of inhibitory lead structures selective for immunoproteasomes that are linked to cytokine production and diseases like cancer and autoimmune disorders.
AB - Constitutive proteasomes and immunoproteasomes shape the peptide repertoire presented by major histocompatibility complex class I (MHC-I) molecules by harboring different sets of catalytically active subunits. Here, we present the crystal structures of constitutive proteasomes and immunoproteasomes from mouse in the presence and absence of the epoxyketone inhibitor PR-957 (ONX 0914) at 2.9 resolution. Based on our X-ray data, we propose a unique catalytic feature for the immunoproteasome subunit β5i/LMP7. Comparison of ligand-free and ligand-bound proteasomes reveals conformational changes in the S1 pocket of β5c/X but not β5i, thereby explaining the selectivity of PR-957 for β5i. Time-resolved structures of yeast proteasome:PR-957 complexes indicate that ligand docking to the active site occurs only via the reactive head group and the P1 side chain. Together, our results support structure-guided design of inhibitory lead structures selective for immunoproteasomes that are linked to cytokine production and diseases like cancer and autoimmune disorders.
UR - http://www.scopus.com/inward/record.url?scp=84857313367&partnerID=8YFLogxK
U2 - 10.1016/j.cell.2011.12.030
DO - 10.1016/j.cell.2011.12.030
M3 - Article
C2 - 22341445
AN - SCOPUS:84857313367
SN - 0092-8674
VL - 148
SP - 727
EP - 738
JO - Cell
JF - Cell
IS - 4
ER -
