Summary information and primary citation
- PDB-id
- 4o8j; SNAP-derived features in text and JSON formats;
DNAproDB
- Class
- ligase-RNA
- Method
- X-ray (2.04 Å)
- Summary
- Crystal structure of rtca, the RNA 3'-terminal phosphate cyclase from pyrococcus horikoshii, in complex with racaaa3'phosphate and adenine.
- Reference
- Desai KK, Bingman CA, Cheng CL, Phillips Jr GN, Raines RT (2014): "Structure of RNA 3'-phosphate cyclase bound to substrate RNA." Rna, 20, 1560-1566. doi: 10.1261/rna.045823.114.
- Abstract
- RNA 3'-phosphate cyclase (RtcA) catalyzes the ATP-dependent cyclization of a 3'-phosphate to form a 2',3'-cyclic phosphate at RNA termini. Cyclization proceeds through RtcA-AMP and RNA(3')pp(5')A covalent intermediates, which are analogous to intermediates formed during catalysis by the tRNA ligase RtcB. Here we present a crystal structure of Pyrococcus horikoshii RtcA in complex with a 3'-phosphate terminated RNA and adenosine in the AMP-binding pocket. Our data reveal that RtcA recognizes substrate RNA by ensuring that the terminal 3'-phosphate makes a large contribution to RNA binding. Furthermore, the RNA 3'-phosphate is poised for in-line attack on the P-N bond that links the phosphorous atom of AMP to N(ϵ) of His307. Thus, we provide the first insights into RNA 3'-phosphate termini recognition and the mechanism of 3'-phosphate activation by an Rtc enzyme.
