Simoes-Barbosa A, Chakrabarti K, Pearson M, Benarroch D, Shuman S, Johnson PJ.

RNA. 2012 Sep;18(9):1656-65. doi: 10.1261/rna.034249.112.

Box H/ACA snoRNAs are preferred substrates for the trimethylguanosine synthase in the divergent unicellular eukaryote Trichomonas vaginalis.

In Trichomonas vaginalis, snRNAs are not capped, but non-intronic snoRNAs are (with three methyls).