Gopalakrishnan, JayachandranChim, Yiu-Cheung FrederickHa, AndrewBasiri, Marcus L.Lerit, Dorothy A.Rusan, Nasser M.Avidor-Reiss, Tomer2013-10-292012Gopalakrishnan, Jayachandran, Yiu-Cheung Frederick Chim, Andrew Ha, Marcus L. Basiri, Dorothy A. Lerit, Nasser M. Rusan, and Tomer Avidor-Reiss. 2012. Tubulin nucleotide status controls sas-4-dependent pericentriolar material recruitment. Nature cell biology 14(8): 865-873.1465-7392http://nrs.harvard.edu/urn-3:HUL.InstRepos:11235648Regulated centrosome biogenesis is required for accurate cell division and for maintaining genome integrity1. Centrosomes consist of a centriole pair surrounded by a protein network known as pericentriolar material (PCM)1. PCM assembly is a tightly regulated, critical step that determines a centrosome’s size and capability2–4. Here, we report a role for tubulin in regulating PCM recruitment via the conserved centrosomal protein Sas-4. Tubulin directly binds to Sas-4; together they are components of cytoplasmic complexes of centrosomal proteins5,6. A Sas-4 mutant, which cannot bind tubulin, enhances centrosomal protein complex formation and has abnormally large centrosomes with excessive activity. These suggest that tubulin negatively regulates PCM recruitment. Whereas tubulin-GTP prevents Sas-4 from forming protein complexes, tubulin-GDP promotes it. Thus, tubulin’s regulation of PCM recruitment depends on its GTP/GDP-bound state. These results identify a role for tubulin in regulating PCM recruitment independent of its well-known role as a building block of microtubules7. Based on its guanine bound state, tubulin can act as a molecular switch in PCM recruitment.en-USJournal Article2013-10-2910.1038/ncb2527