p97 Composition Changes Caused by Allosteric Inhibition Are Suppressed by an On-Target Mechanism that Increases the Enzyme's ATPase Activity.
The AAA ATPase p97/VCP regulates protein homeostasis using a diverse repertoire of cofactors to fulfill its biological functions. Here we use the allosteric p97 inhibitor NMS-873 to analyze its effects on enzyme composition and the ability of cells to adapt to its cytotoxicity. We found that p97 inhibition changes steady state cofactor-p97 composition, leading to the enrichment of a subset of its cofactors and polyubiquitin bound to p97. We isolated cells specifically insensitive to NMS-873 and identified a new mutation (A530T) in p97. A530T is sufficient to overcome the cytotoxicity of NMS-873 and alleviates p97 composition changes caused by the molecule but not other p97 inhibitors. This mutation does not affect NMS-873 binding but increases p97 catalytic efficiency through altered ATP and ADP binding. Collectively, these findings identify cofactor-p97 interactions sensitive to p97 inhibition and reveal a new on-target mechanism to suppress the cytotoxicity of NMS-873.
Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Nam-Gu
NG
Her
Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Julia I
JI
Toth
Conrad Prebys Center for Chemical Genomics, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Chen-Ting
CT
Ma
Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Yang
Y
Wei
Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Khatereh
K
Motamedchaboki
Conrad Prebys Center for Chemical Genomics, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
Eduard
E
Sergienko
Tumor Initiation and Maintenance Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA. Electronic address: petroski@sbpdiscovery.org.
Matthew D
MD
Petroski
D000083:Acetanilides / Q000737:chemistry / Q000494:pharmacology*; D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000494:Allosteric Regulation / Q000187:drug effects; D052160:Benzothiazoles / Q000737:chemistry / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D045325:HCT116 Cells; D006801:Humans; D008958:Models, Molecular; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship
D000083:Acetanilides; D052160:Benzothiazoles; D004791:Enzyme Inhibitors; C000623013:NMS-873; D009687:Nuclear Proteins; D054852:Small Molecule Libraries; D000251:Adenosine Triphosphatases; C404942:p97 ATPase