When small RNAs become smaller: emerging functions of snoRNAs and their derivatives.

Small nucleolar RNAs (snoRNAs) are molecules located in the cell nucleolus and in Cajal bodies. Many scientific reports show that snoRNAs are not only responsible for modifications of other RNAs but also fulfill multiple other functions such as metabolic stress regulation or modulation of alternative splicing. Full-length snoRNAs as well as small RNAs derived from snoRNAs have been implied in human diseases such as cancer or Prader-Willi Syndrome. In this review we describe emerging, non-canonical roles of snoRNAs and their derivatives with the emphasis on their role in human diseases.