Ribonucleoprotein (RNP) is a nucleoprotein that contains RNA, i.e. it is an association that combines ribonucleic acid and protein together (referred also as protein-RNA complexes). A few known examples include the ribosome, the enzyme telomerase, vault ribonucleoproteins, RNase P, hnRNP and small nuclear RNPs (snRNPs), which are implicated in pre-mRNA splicing (spliceosome) and are among the main components of the nucleolus.