Figure 1.

Domain architecture of S. cerevisiae and C. thermophilum Nab2. Both proteins contain an N-terminal domain based on a PWI fold (yellow) followed by an RGG domain (grey), a stretch of Gln-rich sequences (red) and finally a C-terminal domain (blue) that contains CCCH Zn-fingers (seven in S. cerevisiae and five in C. thermophilum). Saccharomyces cerevisiae fingers 5–7 are crucial for control of poly(A) tail length and BLAST analysis (Supplementary Figure S1) indicated that they are most similar to C. thermophilum fingers 3–5.