Figure 4. Online SAXS analysis of PA-PB1, RanBP5 and PA-PB1-RanBP5 complex in solution.

Results are shown for (a) PA-PB1(1-686), (b) RanBP5 and (c) PA-PB1-RanBP5. On the left are the experimental Ln[I(q)] curves with the ab-initio DAMMIN curve fit (blue) using the Damstart (DAMAVER) as an initial constraint and the CRYSOL fit (red) of the closest homologous X-ray structure. The MONSA fit is also shown for PA-PB1-RanBP5 in black. The Chi², to evaluate the statistical similarity between experimental intensities and those computed from a model, are also shown. On the right, the homologous PDB structure of PA-PB1(1-686) from Bat-IAV polymerase is depicted in cartoon and fitted in both the DAMAVER and the MONSA generated envelops of PA-PB1(1-686) which are depicted in grey. PA is coloured in blue, PB1 in green and the NLS of PB1 in magenta. The DAMAVER and MONSA envelop of RanBp5 is coloured in purple. As a comparison, the atomic structure of Kap123P (pdb is: 3W3T) is depicted in cartoon with a sky blue colour alongside the DAMAVER envelop of RanBP5. All envelopes and models are adjusted at the same size scale.