2’-O-methylation on rRNA of Trypanosoma brucei is developmentally regulated

The parasite Trypanosoma brucei cycles between an insect and a mammalian host and is the causative agent of sleeping sickness. Here, we performed genome-wide mapping of 2’-O-methylations (Nms) on trypanosome rRNA using three high-throughput sequencing methods; RibOxi-seq, RiboMeth-seq and 2’-OMe-seq. The sequencing revealed at least ninety-nine Nms guided by eighty-five snoRNAs. This is the largest amount of Nms detected on rRNA of a single cell parasite. Based on RiboMeth-seq, several Nm sites were found to be differentially regulated in the two stages of the parasite propagating in the insect or the mammalian host. Depletion of snoRNAs that guide differentially modified Nm sites affected rRNA biogenesis and the ability of the parasite to cope with growth at elevated temperatures, suggesting that Nm modifications may contribute to the ability of the parasite to cycle between its two hosts.