[chimerax-users] Refine predicted structure by pulling

Dear ChimeraX Users,

There is this AlphaFold prediction: https://alphafold.ebi.ac.uk/entry/P02549. And we know this protein should be more or less in a rod-like shape rather than a globular shape: https://en.wikipedia.org/wiki/Spectrin and related literature such as https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3218374/. I wonder is there a way that we can pull the two ends of the predicted structure while maintaining the secondary structures, mostly alpha-helices in this case, inside ChimeraX?

I am quite new to ChimeraX. I understand this is more fitted to an MD simulation. But I got to know there are options to fit a PDB to a density map. So I wondered if this can be achieved in ChimeraX.

Best, Roden