4BT0

MuB is an AAAplus ATPase that forms helical filaments to control target selection for DNA transposition

Summary for 4BT0

• Entry DOI: 10.2210/pdb4bt0/pdb
• Related: 4BS1 4BT1
• EMDB information: 2398
• Descriptor: TRANSCRIPTIONAL REGULATOR, ADENOSINE-5'-DIPHOSPHATE (3 entities in total)
• Functional Keywords: transcription, aaa+ atpase, dna transposition, nucleoprotein filament, symmetry mismatch
• Biological source: ENTEROBACTERIA PHAGE MU; More
• Total number of polymer chains: 2
• Total formula weight: 28814.70

Authors

Mizuno, N.,Dramicanin, M.,Mizuuchi, M.,Adam, J.,Wang, Y.,Han, Y.W.,Yang, W.,Steven, A.C.,Mizuuchi, K.,Ramon-Maiques, S. (deposition date: 2013-06-12, release date: 2013-07-03, Last modification date: 2024-05-08)

Primary citation

Mizuno, N.,Dramicanin, M.,Mizuuchi, M.,Adam, J.,Wang, Y.,Han, Y.W.,Yang, W.,Steven, A.C.,Mizuuchi, K.,Ramon-Maiques, S.
Mub is an Aaa+ ATPase that Forms Helical Filaments to Control Target Selection for DNA Transposition.
Proc.Natl.Acad.Sci.USA, 110:E2441-, 2013

PubMed Abstract: MuB is an ATP-dependent nonspecific DNA-binding protein that regulates the activity of the MuA transposase and captures target DNA for transposition. Mechanistic understanding of MuB function has previously been hindered by MuB's poor solubility. Here we combine bioinformatic, mutagenic, biochemical, and electron microscopic analyses to unmask the structure and function of MuB. We demonstrate that MuB is an ATPase associated with diverse cellular activities (AAA+ ATPase) and forms ATP-dependent filaments with or without DNA. We also identify critical residues for MuB's ATPase, DNA binding, protein polymerization, and MuA interaction activities. Using single-particle electron microscopy, we show that MuB assembles into a helical filament, which binds the DNA in the axial channel. The helical parameters of the MuB filament do not match those of the coated DNA. Despite this protein-DNA symmetry mismatch, MuB does not deform the DNA duplex. These findings, together with the influence of MuB filament size on strand-transfer efficiency, lead to a model in which MuB-imposed symmetry transiently deforms the DNA at the boundary of the MuB filament and results in a bent DNA favored by MuA for transposition.

PubMed: 23776210
DOI: 10.1073/PNAS.1309499110

Experimental method

ELECTRON MICROSCOPY (17 Å)