Extended Data Fig. 4: Cryo-EM analysis of S2-connected duplex pairs from non-homologous dsDNA reactions.
From: Mechanism of strand exchange from RecA–DNA synaptic and D-loop structures
a, The 5′ end of the filament, but not the 3′ end, produces classes with conspicuously short duplexes. Reconstruction after 3D refinement of paired duplexes that have duplexH or duplexI. Top, maps of classes with short duplexes. Bottom, maps of classes from the same 3D classification but with regular, long duplexes. The black circle highlights the difference in duplex length. Maps are coloured by the duplex tilt (5′, cyan; 3′, purple), with S2 DNA in red. Overall resolution, from gold-standard refinement procedure, and particle numbers are also shown. b, Charts show the number of particles with S2-connected duplex pairs for the non-homologous 67-bp dsDNA dataset. Each chart is of the series that contains the first duplex in common. Pairs of duplexes starting at RecAC are omitted, as they are shown in Fig. 1d. The dataset was collected once. c, Charts show the number of particles with S2-connected duplex pairs for the non-homologous 120-bp dsDNA dataset as in b. Pairs of duplexes starting at RecAC are omitted as they are shown in Fig. 1l. The dataset was collected once.
