We study RNA modifications and their role in germ cell proliferation and differentiation. During development cells constantly face a decision between cell division and differentiation. Regulation of gene expression is key to this decision making process and RNA is at the centre of many gene regulatory processes. There are more than 150 distinct chemical modifications found on RNA. RNA modifications control the processing, stability, expression and function of diverse types of RNAs. The germline development of C. elegans provides an ideal model system to study the role of RNA modifications and RNA modifying enzymes in cell proliferation and differentiation.