Evaluation Summary:
This paper describes a biochemical analysis of the roles of Ub chain length on Ub-dependent segregase activity of yeast and human p97 and the role of UBX proteins on the disassembly of the CMG replicative helicase complex. The human p97 complex does not segregate substrates with shorter ubiquitin chains as efficiently as does the yeast complex but the human complex can be enhanced in vitro by 3 UBX proteins - FAF1, FAF2, and UBXN7. Cellular studies indicate a partial role for FAF1 and UBXN7 in cells. The paper would be strengthened by additional mechanistic understanding of how the UBX domain functions in activation of segregase activity and the contribution of this pathway in cells.
(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)