NOPCHAP1 is a PAQosome cofactor that helps loading NOP58 on RUVBL1/2 during box C/D snoRNP biogenesis

Yoann Abel, Ana C.F. Paiva, Jonathan Bizarro, Marie Eve Chagot, Paulo E. Santo, Marie Cécile Robert, Marc Quinternet, Franck Vandermoere, Pedro M.F. Sousa, Philippe Fort, Bruno Charpentier, Xavier Manival, Tiago M. Bandeiras, Edouard Bertrand, Céline Verheggen

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)


The PAQosome is a large complex composed of the HSP90/R2TP chaperone and a prefoldin-like module. It promotes the biogenesis of cellular machineries but it is unclear how it discriminates closely related client proteins. Among the main PAQosome clients are C/D snoRNPs and in particular their core protein NOP58. Using NOP58 mutants and proteomic experiments, we identify different assembly intermediates and show that C12ORF45, which we rename NOPCHAP1, acts as a bridge between NOP58 and PAQosome. NOPCHAP1 makes direct physical interactions with the CC-NOP domain of NOP58 and domain II of RUVBL1/2 AAA+ ATPases. Interestingly, NOPCHAP1 interaction with RUVBL1/2 is disrupted upon ATP binding. Moreover, while it robustly binds both yeast and human NOP58, it makes little interactions with NOP56 and PRPF31, two other closely related CC-NOP proteins. Expression of NOP58, but not NOP56 or PRPF31, is decreased in NOPCHAP1 KO cells. We propose that NOPCHAP1 is a client-loading PAQosome cofactor that selects NOP58 to promote box C/D snoRNP assembly.

Original languageEnglish
Pages (from-to)1094-1113
Number of pages20
JournalNucleic Acids Research
Issue number2
Publication statusPublished - 25 Jan 2021


Dive into the research topics of 'NOPCHAP1 is a PAQosome cofactor that helps loading NOP58 on RUVBL1/2 during box C/D snoRNP biogenesis'. Together they form a unique fingerprint.

Cite this