RNomics: Exploring the World of Non-Protein Coding (npc) RNAs
With experimental high-throughput cDNA library screening and biocomputational methods we identify and characterize novel npcRNAs from diverse model organisms. In contrast to mRNAs, which are templates for translating proteins, npcRNAs exhibit various functions in different compartments and developmental stages of the cell. Small nucleolar RNAs (snoRNAs), one of the largest classes of npcRNAs, guide post-transcriptional modifications of other RNAs that are crucial for appropriate RNA folding as well as for RNA-RNA and RNA-protein interactions. Detailed comparisons of paralog snoRNAs revealed, in addition to trans-duplication, a novel, cis-duplication distribution strategy with insertions near to the original loci. Some snoRNAs coevolved with their modification target sites, demonstrating the close interaction of complementary regions. Some target sites modified by snoRNAs are changed, added or lost, documenting a high degree of evolutionary plasticity of npcRNAs. The evolutionary history of npcRNAs in mammalian species is one of our main subjects to explore the world of RNomics.