Key assembly factor specifically required for the stability of axonemal dynein heavy chains in cytoplasm. Component of the PAQosome complex which is responsible for the biogenesis of several protein complexes and which consists of R2TP complex members RUVBL1, RUVBL2, RPAP3 and PIH1D1, URI complex members PFDN2, PFDN6, PDRG1, UXT and URI1 as well as ASDURF, POLR2E and DNAAF10/WDR92 (By similarity). Interacts with PIH1D1; the interaction associates DNAAF10 with the R2TP complex (By similarity). Interacts with several dynein axonemal assembly factors (By similarity).