Fig. 6: Observation of real-time Abo1 conformational change by HS-AFM shows stochastic AAA+ ring symmetry breaking.
From: Structural basis of nucleosome assembly by the Abo1 AAA+ ATPase histone chaperone
a Representative high-speed AFM image of Abo1 hexamer immobilized on an APTES-treated mica surface in the absence of nucleotide. Scale bar = 20 nm. b Full width at half-maximum (FWHM) histogram of Abo1 molecules fit to a Gaussian distribution with a mean ± SD of 19.8 ± 2.6 nm. c AFM data simulations of Abo1 in different nucleotide states using models from cryo-EM data. Top panels show “bottom view” from the AAA2 ___domain side, and bottom panels show “top view” from the AAA1 ___domain side. Scale bar = 5 nm. d Snapshots of an Abo1 molecule undergoing conformational change upon ATP addition. Movies were taken at a frame rate of 5 Hz. Scale bar = 5 nm. e Analysis of the position of Abo1 ring opening (gray boxes) sorted by subunit according to time shows random subunit activation. Additional examples shown in Supplementary Fig. 17.
