Summary information and primary citation
- PDB-id
-
3epl;
DSSR-derived features in text and
JSON formats
- Class
- transferase-RNA
- Method
- X-ray (3.6 Å)
- Summary
- Crystallographic snapshots of eukaryotic
dimethylallyltransferase acting on trna: insight into trna
recognition and reaction mechanism
- Reference
-
Zhou C, Huang RH (2008): "Crystallographic
snapshots of eukaryotic dimethylallyltransferase acting
on tRNA: insight into tRNA recognition and reaction
mechanism." Proc.Natl.Acad.Sci.Usa,
105, 16142-16147. doi: 10.1073/pnas.0805680105.
- Abstract
- Hypermodifications near the anticodon of tRNA are
fundamental for the efficiency and fidelity of protein
synthesis. Dimethylallyltransferase (DMATase) catalyzes
transfer of a dimethylallyl moiety from dimethylallyl
pyrophosphate to N6 of A37 in certain tRNAs. Here we
present the crystal structures of Saccharomyces cerevisiae
DMATase-tRNA(Cys) complex in four distinct forms, which
provide snapshots of the RNA modification reaction
catalyzed by DMATase. The structures reveal that the enzyme
recognizes the tRNA substrate through indirect sequence
readout. The targeted nucleotide A37 flips out from the
anticodon loop of tRNA and flips into a channel in DMATase,
where it meets its reaction partner di methylallyl
pyrophosphate, which enters the channel from the opposite
end. Structural changes accompanying the transfer reaction
taking place in the crystal result in disengagement of
DMATase-tRNA interaction near the reaction center. In
addition, structural comparison of DMATase in the complex
with unliganded bacterial DMATase provides a molecular
basis of ordered substrate binding by DMATase.
