Quantitative interaction mapping reveals an extended UBX domain in ASPL that disrupts functional p97 hexamers


  • 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


  • Nature Communications


  • Nat Commun 7: 13047


  • 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.