8Q3W

ATP-bound IstB in complex to duplex DNA

Summary for 8Q3W

• Entry DOI: 10.2210/pdb8q3w/pdb
• EMDB information: 18136 3031 3032
• Descriptor: Insertion sequence IS5376 putative ATP-binding protein, DNA (48-MER) Target DNA FW, DNA (48-MER) Traget DNA Rv, ... (5 entities in total)
• Functional Keywords: dna transposition, transposon, transpososome, aaa+ atpases, target dna, is21, istb, insertion sequence, dna binding protein, cryo-electron microscopy.
• Biological source: Geobacillus stearothermophilus; More
• Total number of polymer chains: 12
• Total formula weight: 338324.27

Authors

de la Gandara, A.,Spinola-Amilibia, M.,Araujo-Bazan, L.,Nunez-Ramirez, R.,Berger, J.M.,Arias-Palomo, E. (deposition date: 2023-08-04, release date: 2024-07-10)

Primary citation

de la Gandara, A.,Spinola-Amilibia, M.,Araujo-Bazan, L.,Nunez-Ramirez, R.,Berger, J.M.,Arias-Palomo, E.
Molecular basis for transposase activation by a dedicated AAA+ ATPase.
Nature, 630:1003-1011, 2024

PubMed Abstract: Transposases drive chromosomal rearrangements and the dissemination of drug-resistance genes and toxins. Although some transposases act alone, many rely on dedicated AAA+ ATPase subunits that regulate site selectivity and catalytic function through poorly understood mechanisms. Using IS21 as a model transposase system, we show how an ATPase regulator uses nucleotide-controlled assembly and DNA deformation to enable structure-based site selectivity, transposase recruitment, and activation and integration. Solution and cryogenic electron microscopy studies show that the IstB ATPase self-assembles into an autoinhibited pentamer of dimers that tightly curves target DNA into a half-coil. Two of these decamers dimerize, which stabilizes the target nucleic acid into a kinked S-shaped configuration that engages the IstA transposase at the interface between the two IstB oligomers to form an approximately 1 MDa transpososome complex. Specific interactions stimulate regulator ATPase activity and trigger a large conformational change on the transposase that positions the catalytic site to perform DNA strand transfer. These studies help explain how AAA+ ATPase regulators-which are used by classical transposition systems such as Tn7, Mu and CRISPR-associated elements-can remodel their substrate DNA and cognate transposases to promote function.

PubMed: 38926614
DOI: 10.1038/s41586-024-07550-6

Experimental method

ELECTRON MICROSCOPY (3.18 Å)