Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Protein domain assignments are based on AlphaFold predictions92,93, ToxoDB75 and FoldSeek103. Regions resolved in the cryo-EM maps are indicated with green boxes.