Figure 1.

Distinct portions of the N-terminal half of Erb1 are required for growth. (A) Schematic representation of the heterotrimeric subcomplex formed between Ytm1, Erb1 and Nop7. (B) PyMOL structure depicting the Erb1 binding site (yellow) in 25S rRNA domain I (purple), and the Nop7 protein (blue) bound to 5.8S rRNA/25S rRNA domain III (green) in preribosomes (PDB ID: 3JCT). (C) Schematic representation of internal deletions of highly conserved residues in the N-terminal half of Erb1. (D) Growth of GAL-ERB1 strains containing plasmids encoding wildtype Erb1 or mutant erb1 proteins under the control of the ERB1 promoter, was assayed by spotting ten-fold serial dilutions on solid media containing galactose (C-Trp+Gal) or glucose (C-Trp+Glu). The GAL-ERB1 strain containing the empty vector (pRS314) is included as a negative control.