Extended Data Fig. 5: Interactions of the biogenesis factors Loc1, Noc2 and Rrp17 in state E2 and of the newly modeled helix of Nop53 in state NE1.

a, Cartoon representation of the interaction between Rrp17 (red), Spb1-MTD (teal) and H64 (blue). A plot of residue conservation scores as implemented in Jalview⁶⁶ from on an alignment of 15 representative fungal Rrp17 homologs is shown below the model. Residues with an arbitrarily chosen conservation score >7 are highlighted and shown as sticks in the structural model. b, Cartoon representation of the interaction between Rrp17 (red), eL30 (green), Spb4-D1 (yellow), the Spb1 helical element (teal) and H34 (gray). Conserved residues (identified in plot) are shown as sticks (same criteria as in panel a). c, Cartoon representation of the interaction between the C-terminal helix of Rrp17 (red), Spb1-MTD (teal) and H64 (blue). Adjacent rRNA helices H90 (green) and H92 (orange) are also shown. Conserved residues (identified in plot) are shown as sticks (same criteria as in panel A). d, Detail of the position and interactions of Loc1 within the state E2 60S particle. The cartoon representation shows the interaction of Loc1 (purple) with various RBFs and rRNA elements. Model building and validation was aided by a crosslink between Loc1 and Brx1 (green connected spheres)³¹. e, Cartoon representation of the Noc2 (green)/Noc3(blue) interaction highlighting the conserved Noc module (orange) of Noc3 and the extended N-terminus of Noc2, which extends into the 60 S core (inset). Positions of crosslinks between Noc2 and Noc3 and Noc2 and Nip7 are shown as green connected spheres³¹. The interaction between Noc2/Noc3 is analogous to the interaction between Noc4 and Nop14, revealing Noc2 and Nop14 to be structural paralogs⁶⁷. f, State NE1 with Nop53 colored maroon for emphasis. The newly modeled Nop53 helix is boxed and expanded in the inset. Surface view of the helix is shown for clarity.