Fig. 1
From: The emerging roles of non-coding competing endogenous RNA in hepatocellular carcinoma
The classification of coding and noncoding RNA. Eukaryotic mRNA molecules are usually composed of small segments of the original gene and are generated by a process of cleavage and rejoining from an original precursor RNA (pre-mRNA) molecule, which is an exact copy of the gene. Noncoding RNA (ncRNA) mainly include long non-coding RNA (lncRNA), microRNA (miRNA), pseudogene, circular RNA (circRNA), small interfering RNA (siRNA), piwi-interacting RNA (piRNA), small nucleolar RNA (snoRNA), small nuclear RNA (snRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA)