PT  - JOURNAL ARTICLE
AU  - Nina Schweizer
AU  - Laurence Haren
AU  - Ricardo Viais
AU  - Cristina Lacasa
AU  - Ilaria Dutto
AU  - Andreas Merdes
AU  - Jens Lüders
TI  - Sub-centrosomal mapping identifies augmin-γTuRC as part of a centriole-stabilizing scaffold
AID  - 10.1101/2020.11.18.384156
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.11.18.384156
4099  - http://biorxiv.org/content/early/2020/11/18/2020.11.18.384156.short
4100  - http://biorxiv.org/content/early/2020/11/18/2020.11.18.384156.full
AB  - Centriole biogenesis and maintenance are crucial for cells to generate cilia and assemble centrosomes that function as microtubule organizing centers (MTOCs). Centriole biogenesis and MTOC function both require the microtubule nucleator γ-tubulin ring complex (γTuRC). The widely accepted view is that γTuRC localizes to the pericentriolar material (PCM), where it nucleates microtubules. γTuRC has also been observed at centriolar regions that lack PCM, but the significance of these findings is unclear. Here we have used expansion microscopy to map spatially and functionally distinct sub-populations of centrosomal γTuRC including in the centriole lumen. Luminal localization is mediated by augmin and both complexes are linked to the centriole inner scaffold through POC5. Disruption of luminal localization impairs centriole stability and cilia assembly, defects that are also observed in γTuRC mutant fibroblasts derived from a patient suffering from microcephaly with chorioretinopathy. These results identify a novel, non-canonical role of augmin-γTuRC in the centriole lumen that is linked to human disease.Competing Interest StatementThe authors have declared no competing interest.