Comparative modeling and SAXS profile fitting using the Chimera visualization package. MODELLER was used to add missing residues and a His tag on the C-terminal domain of Nup133 (see sequence alignment in the upper right window). Three models were generated (red, green and blue) using a template structure [PDB:3KFO] (white). The FoXS interface (lower left window) was used to fit the profiles computed for the X-ray structure and the models to the experimental SAXS profile (lower right window). A) model window, B) sequence alignment window, C) model scores, D) FoXS interface window, and E) FoXS output window.