RRC ID 76916
Author Zhu Z, Becam I, Tovey CA, Elfarkouchi A, Yen EC, Bernard F, Guichet A, Conduit PT.
Title Multifaceted modes of γ-tubulin complex recruitment and microtubule nucleation at mitotic centrosomes.
Journal J Cell Biol
Abstract Microtubule nucleation is mediated by γ-tubulin ring complexes (γ-TuRCs). In most eukaryotes, a GCP4/5/4/6 "core" complex promotes γ-tubulin small complex (γ-TuSC) association to generate cytosolic γ-TuRCs. Unlike γ-TuSCs, however, this core complex is non-essential in various species and absent from budding yeasts. In Drosophila, Spindle defective-2 (Spd-2) and Centrosomin (Cnn) redundantly recruit γ-tubulin complexes to mitotic centrosomes. Here, we show that Spd-2 recruits γ-TuRCs formed via the GCP4/5/4/6 core, but Cnn can recruit γ-TuSCs directly via its well-conserved CM1 domain, similar to its homologs in budding yeast. When centrosomes fail to recruit γ-tubulin complexes, they still nucleate microtubules via the TOG domain protein Mini-spindles (Msps), but these microtubules have different dynamic properties. Our data, therefore, help explain the dispensability of the GCP4/5/4/6 core and highlight the robustness of centrosomes as microtubule organizing centers. They also suggest that the dynamic properties of microtubules are influenced by how they are nucleated.
Volume 222(10)
Published 2023-10-2
DOI 10.1083/jcb.202212043
PII 276255
PMID 37698931
PMC PMC10497398
MeSH Animals Centrosome* Cytoskeletal Proteins* / genetics Cytosol Drosophila Drosophila Proteins / genetics Homeodomain Proteins / genetics Microtubule-Organizing Center* Microtubules* / genetics Tubulin* / genetics
IF 8.811
Drosophila HMJ23752