3WFQ

tRNA processing enzyme complex 1

Summary for 3WFQ

• Entry DOI: 10.2210/pdb3wfq/pdb
• Related: 3WFO 3WFP 3WFR 3WFS
• Descriptor: RNA (73-MER), Poly A polymerase (2 entities in total)
• Functional Keywords: terminal nucleotide transferase, transferase-rna complex, transferase/rna
• Biological source: synthetic construct; More
• Total number of polymer chains: 8
• Total formula weight: 321952.16

Authors

Yamashita, S.,Takeshita, D.,Tomita, K. (deposition date: 2013-07-23, release date: 2014-01-01, Last modification date: 2023-11-08)

Primary citation

Yamashita, S.,Takeshita, D.,Tomita, K.
Translocation and rotation of tRNA during template-independent RNA polymerization by tRNA nucleotidyltransferase
Structure, 22:315-325, 2014

PubMed Abstract: The 3'-terminal CCA (CCA-3' at positions 74-76) of tRNA is synthesized by CCA-adding enzyme using CTP and ATP as substrates, without a nucleic acid template. In Aquifex aeolicus, CC-adding and A-adding enzymes collaboratively synthesize the CCA-3'. The mechanism of CCA-3' synthesis by these two enzymes remained obscure. We now present crystal structures representing CC addition onto tRNA by A. aeolicus CC-adding enzyme. After C₇₄ addition in an enclosed active pocket and pyrophosphate release, the tRNA translocates and rotates relative to the enzyme, and C₇₅ addition occurs in the same active pocket as C₇₄ addition. At both the C₇₄-adding and C₇₅-adding stages, CTP is selected by Watson-Crick-like hydrogen bonds between the cytosine of CTP and conserved Asp and Arg residues in the pocket. After C₇₄C₇₅ addition and pyrophosphate release, the tRNA translocates further and drops off the enzyme, and the CC-adding enzyme terminates RNA polymerization.

PubMed: 24389024
DOI: 10.1016/j.str.2013.12.002

Experimental method

X-RAY DIFFRACTION (3.619 Å)