7LCC

Helitron transposase bound to LTS

Summary for 7LCC

• Entry DOI: 10.2210/pdb7lcc/pdb
• EMDB information: 23271
• Descriptor: Helraiser K1068Q, LTS, ZINC ION (3 entities in total)
• Functional Keywords: helitron, transposase, evolution, gene editing, gene capture, rolling circle, replication, recombination, nuclease, helicase, relaxase
• Biological source: synthetic construct; More
• Total number of polymer chains: 2
• Total formula weight: 177476.95

Authors

Kosek, D.,Dyda, F. (deposition date: 2021-01-10, release date: 2021-08-25, Last modification date: 2024-05-29)

Primary citation

Kosek, D.,Grabundzija, I.,Lei, H.,Bilic, I.,Wang, H.,Jin, Y.,Peaslee, G.F.,Hickman, A.B.,Dyda, F.
The large bat Helitron DNA transposase forms a compact monomeric assembly that buries and protects its covalently bound 5'-transposon end.
Mol.Cell, 81:4271-4286.e4, 2021

PubMed Abstract: Helitrons are widespread eukaryotic DNA transposons that have significantly contributed to genome variability and evolution, in part because of their distinctive, replicative rolling-circle mechanism, which often mobilizes adjacent genes. Although most eukaryotic transposases form oligomers and use RNase H-like domains to break and rejoin double-stranded DNA (dsDNA), Helitron transposases contain a single-stranded DNA (ssDNA)-specific HUH endonuclease domain. Here, we report the cryo-electron microscopy structure of a Helitron transposase bound to the 5'-transposon end, providing insight into its multidomain architecture and function. The monomeric transposase forms a tightly packed assembly that buries the covalently attached cleaved end, protecting it until the second end becomes available. The structure reveals unexpected architectural similarity to TraI, a bacterial relaxase that also catalyzes ssDNA movement. The HUH active site suggests how two juxtaposed tyrosines, a feature of many replication initiators that use HUH nucleases, couple the conformational shift of an α-helix to control strand cleavage and ligation reactions.

PubMed: 34403695
DOI: 10.1016/j.molcel.2021.07.028

Experimental method

ELECTRON MICROSCOPY (3.66 Å)