RNA cyclases are a family of RNA-modifying enzymes that are conserved in all cellular organisms. They catalyse the ATP-dependent conversion of the 3'-phosphate to the 2',3'-cyclic phosphodiester at the end of RNA, in a reaction involving formation of the covalent AMP-cyclase intermediate . The structure of RTC demonstrates that RTCs are comprised two domain. The larger domain contains an insert domain of approximately 100 amino acids .
RNA cyclases are a family of RNA-modifying enzymes that are conserved in eukaryotes, bacteria and archaea. Type 1 RNA 3'-terminal phosphate cyclases (EC) [PUBMED:9184239, PUBMED:2199762] catalyse the conversion of 3'-phosphate to a 2',3'-cyclic phosphodiester at the end of RNA: