Families of H/ACA ncRNA molecules in trypanosomatids.

H/ACA molecules are small nucleolar RNAs (snoRNAs) that guide the conversion of a uridine into a pseudouridine. This modification is crucial for ribosomal RNA (rRNA) function. In addition, H/ACA RNA also function in ribosomal RNA processing. Unlike the double hairpin structure of H/ACA molecules in other organisms, H/ACA molecules in Trypanosomes have a single hairpin structure. Here we describe the repertoire of the 46 published H/ACA molecules in Trypanosoma brucei, as well as identify the orthologous counterparts in other Trypanosomatids enlarging the H/ACA collection in this family to over 300.