Figure 1.

Structure probing and genetic data indicate repositioning of Rps3. (A) Primer extension pattern of ribosomes from n = 3 biological replicates of WT and ΔLtv1 cells in the presence (+) or absence (–) of DMS. Differentially accessible residues as quantified below are highlighted in red (exposed) or blue (protected). Gray bars show ΔLtv1, and black bars show WT. (B and C) Quantification was done using Image Lab 6.0 and normalized to band 1, which causes a stop in all lanes. Differentially accessible residues are shown in the secondary (B) and tertiary (C) structure of the head rRNA. Rps3 (red), Rps10 (blue), Rps20 (green), Rps29 (cyan), Asc1 (yellow), and Rps17 (brown) binding sites are indicated in the colored boxes (B) or in the structure of mature 40S ribosome (C; PDB ID: 4V88). Enp1 and a peptide of Ltv1 are shown in purple. Their position was derived from a superposition of 40S in 4V88 and pre-40S in 6FAI. (D) Genetic interactions between Ltv1 deletion and mutations at the interface between Rps3 and Rps17. (E) Genetic interactions between Ltv1 deletion and mutations in the Rps3 protein network. Fold-changes were determined by comparison of the effects from Rps3, Rps20, or Rps17 mutations in the presence or absence of Ltv1. Data in D and E are three to five technical repeats of 3–12 biological replicates. Error bars represent the SEM, and significance was determined using an unpaired t test. ****, P < 0.0001.