Figure EV1. Conservation of transporter C‐terminal MIMs and control stainings for antibodies.

1. The C‐termini of indicated transporters were aligned using Clustal Omega software. Conserved residues of candidate MIMs are highlighted by blue boxes; (*)—fully conserved residue; (:)—residues of strongly similar properties; (.)—residues of weakly similar properties. The previously described endocytic motif in DAT is highlighted by the green dashed box.
2. Cryosections of mouse brain were prepared covering the dorsal raphe and stained with hematoxylin/eosin. The black box indicates the approximate area of immunofluorescence images in Figs 1B and 3A and B. AQ = cerebral aqueduct.
3. Mouse brain sections were subjected to immunofluorescence microscopy as described under “Materials and Methods,” with or without polyclonal antibodies for either TPH or MAD2, as indicated. Scale bars represent 100 μm.