Extended Data Fig. 5: Human versus yeast interactions between TRRAP/Tra1, SUPT20/Spt20 and TAF12/Taf12.

a. Location of the SUPT20H/Spt20 C-terminal region after superposition of human TRRAP and yeast Tra1. The C-terminal helix of yeast Spt20 aligns with helix one of the SUPT20H linker. b. The sequence alignment of the SUPT20H/Spt20 C-terminal regions for 24 metazoan (SUPT20H) and two yeast (Spt20) species shows that the SUPT20H CTD is highly conserved in vertebrates, while it does not appear to exist in yeast. Secondary structure elements are indicated above the alignment. *: D291 forms a salt bridge with TRRAP R3746 (Fig. 5f). Vertebrate and invertebrate sequences were pre-aligned to human SUPT20H, regions corresponding to the structured part in a were extracted and realigned with the yeast sequences corresponding to the region from helix 1 in a to the C-terminus. c. Relative location of the TAF12 N-terminal region, based on the superposition shown in a. In yeast, an N-terminal linker of Taf12 wraps around the inside of the Tra1 FAT domain, while human TAF12 contacts TRRAP in a different location. The structured N-terminus of yeast Taf12 is located in the same relative position as the human SUPT20H CTD. d. Zoomed-out sequence alignment of 24 metazoan and two yeast TAF12/Taf12 subunits. Structured regions are colored as in c and the region corresponding to the linker in yeast is indicated. Aligned regions in b and d are colored by similarity in gray scale (annotated in d). In yeast, Taf12 contains a considerably longer N-terminus that appears to be unique to yeast. Sequences are labeled as: Scientific organism name (Uniprot or NCBI accession code). The organism selection corresponds to Extended Data Fig. 1a and Supplementary Table 1.