Crystal structure of γ-tubulin complex protein GCP4 provides insight into microtubule nucleation

Autor: Martine Knibiehler, Valérie Guillet, Cécile Chemin, Marie-Hélène Remy, Justin M. Kollman, Andreas Merdes, Lynn Gregory-Pauron, David A. Agard, Lionel Mourey, Cécile Bon, Brigitte Raynaud-Messina
Přispěvatelé: Institut de pharmacologie et de biologie structurale (IPBS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées
Rok vydání: 2011
Předmět:
Zdroj: Nature Structural and Molecular Biology
Nature Structural and Molecular Biology, Nature Publishing Group, 2011, 18, pp.915-919. ⟨10.1038/nsmb.2083⟩
ISSN: 1545-9985
1545-9993
DOI: 10.1038/nsmb.2083
Popis: International audience; Microtubule nucleation in all eukaryotes involves g-tubulin small complexes (gTuSCs) that comprise two molecules of g-tubulin bound to g-tubulin complex proteins (GCPs) GCP2 and GCP3. In many eukaryotes, multiple gTuSCs associate with GCP4, GCP5 and GCP6 into large g-tubulin ring complexes (gTuRCs). Recent cryo-EM studies indicate that a scaffold similar to gTuRCs is formed by lateral association of gTuSCs, with the C-terminal regions of GCP2 and GCP3 binding g-tubulin molecules. However, the exact role of GCPs in microtubule nucleation remains unknown. Here we report the crystal structure of human GCP4 and show that its C-terminal domain binds directly to g-tubulin. The human GCP4 structure is the prototype for all GCPs, as it can be precisely positioned within the gTuSC envelope, revealing the nature of protein-protein interactions and conformational changes regulating nucleation activity.
Databáze: OpenAIRE