One possible explanation for this curious observation might be that Crlz-1 as a UTP-3 constituent would be additionally required for the biogenesis and/or processing of rRNA to match up with a very rapid proliferation of pre-B or GC centroblast B cells and their derived lymphomas, but could be substituted by some other factors in different cells as exemplified by a recent report that DCAF13 is required for the rRNA maturation and ribosome biogenesis in the case of rapidly proliferating T cells.35 The gene discussed is DCAF13; the disease is lymphoma.