RPL24 has the greatest effect on CB number and the least effect on ribosome integrity. (A) Quantification of CB numbers per nucleus in HeLa cells after siRNA knockdown of control (NT) or ribosomal proteins for 72 h. RPL14 and RPL24 are positive hits identified in the siRNA screen to increase the CB number. RPL6 and RPL17 were not enriched in proximity biotinylation. Number of replicates: siNT = 7; siRPL14 = 6; siRPL24, siRPL6 and siRPL17 = 5. P values are obtained by Kruskal–Wallis test followed by the Dunn test with Bonferonni correction. **, P < 0.01, ****, P < 0.0001. Whiskers are plotted by the Tukey method. (B) 28S/18S rRNA ratio of RNA extracted from HeLa cells after respective siRNA knockdown. Number of replicates = 3. P values are obtained by unpaired t tests with siNT. **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. Error bar, SD. (C) Western blot analysis of ribosomal protein expression in HeLa cells after respective siRNA knockdown. Tubulin is used as a loading control. Number 1–3 stands for independent replicates. Source data are available for this figure: SourceData F6.