Figure 3. Human and yeast exosome cores: extensive similarities of the central scaffolds.

(A) Structure of the hEXO-9 barrel from the cryo-EM reconstruction bound to hMPP6 (teal). In hEXO-9, the cap proteins are shown in the same colors as in panel A and the base proteins are in light blue (for the Rrp41-like proteins hRRP41, hRRP46 and hMTR3) and light green (for the Rrp42-like proteins hRRP42, hRRP43 and hRRP45). The definition of Rrp41-like and Rrp42-like follows the original description in (Lorentzen et al., 2005). The superposition of the human and yeast scaffolds is shown in Figure 3—figure supplement 1. (B–D) Zoom-ins at specific regions of human hEXO-9 described in text, with cryo-EM density superposed. (E) Zoom-in at hMPP6 fragment bound to hRRP40, with cryo-EM density superposed.

Figure 3—figure supplement 1. Similar scaffolds of yeast and human exosome cores.

The cryo-EM structure of hEXO-9 (in the same colors as in Figure 3) is shown superposed to the structure of yExo-9 (Makino et al., 2015); PDB: 5c0w.

Figure 3—figure supplement 2. Zoomed in views of the hEXO-9 subunits.

Representative parts of the hEXO-9 core exosome complex from the hEXO-10 EM density map, showing secondary structure elements and resolved side chains. Subunit names and highlighted sequences are marked below corresponding views.