Quantitative interaction mapping reveals an extended UBX domain in ASPL that disrupts functional p97 hexamers
Authors
- A. Arumughan
- Y. Roske
- C. Barth
- L. Lleras Forero
- K. Bravo-Rodriguez
- Al. Redel
- S. Kostova
- E. McShane
- R. Opitz
- K. Faelber
- K. Rau
- T. Mielke
- O. Daumke
- M. Selbach
- E. Sanchez-Garcia
- O. Rocks
- D. Panáková
- U. Heinemann
- E.E. Wanker
Journal
- Nature Communications
Citation
- Nat Commun 7: 13047
Abstract
Interaction mapping is a powerful strategy to elucidate the biological function of protein assemblies and their regulators. Here, we report the generation of a quantitative interaction network, directly linking 14 human proteins to the AAA+ ATPase p97, an essential hexameric protein with multiple cellular functions. We show that the high-affinity interacting protein ASPL efficiently promotes p97 hexamer disassembly, resulting in the formation of stable p97:ASPL heterotetramers. High-resolution structural and biochemical studies indicate that an extended UBX domain (eUBX) in ASPL is critical for p97 hexamer disassembly and facilitates the assembly of p97:ASPL heterotetramers. This spontaneous process is accompanied by a reorientation of the D2 ATPase domain in p97 and a loss of its activity. Finally, we demonstrate that overproduction of ASPL disrupts p97 hexamer function in ERAD and that engineered eUBX polypeptides can induce cell death, providing a rationale for developing anti-cancer polypeptide inhibitors that may target p97 activity.