Client-loading PAQosome/R2TP complex cofactor that selects NOP58 to promote box C/D small nucleolar ribonucleoprotein (snoRNP) assembly. Acts as a bridge between NOP58 and the R2TP complex via RUVBL1:RUVBL2. . This is the function of Ensembl gene identifier ENSG00000151131 (NOPCHAP1, NOP protein chaperone 1).