Fig. 3: Structural basis for the assembly of multiple PabRPA molecules on ssDNA.
From: DNA-binding mechanism and evolution of replication protein A
a Negative-staining microscopy of PabRPA bound to M13 ssDNA plasmid. The experiment was repeated three times independently. b Cryo-EM structures of PabRPA bound to a poly-dT100 reveals two interacting modes. Two independent datasets were collected and revealed different levels of condensation of ssDNA-PabRPA complexes: a “relaxed” one and a “condensed” one. Crystal structures of the poly-dT20-bound Tri-C and the OB-1 domain were rigid-body fitted in each cryo-EM 3D reconstruction. Cryo-EM maps are contoured at a level of 6 rmsd. c Specific binding of Rpa3 (50, 100, 200 µM; n = 3) to immobilized Rpa1-Nter domains (AROD-OB-1) measured by BLI. Source data are provided as a source data file. d AlphaFold2 predictions of the Tri-C(n)/OB-1(n + 1) complex.
