Structure of the SAS-6 cartwheel hub from Leishmania major.
van Breugel, M., Wilcken, R., McLaughlin, S.H., Rutherford, T.J., Johnson, C.M.(2014) Elife 3: e01812-e01812
- PubMed: 24596152 
- DOI: https://doi.org/10.7554/eLife.01812
- Primary Citation of Related Structures:  
4CKM, 4CKN, 4CKP - PubMed Abstract: 
Centrioles are cylindrical cell organelles with a ninefold symmetric peripheral microtubule array that is essential to template cilia and flagella. They are built around a central cartwheel assembly that is organized through homo-oligomerization of the centriolar protein SAS-6, but whether SAS-6 self-assembly can dictate cartwheel and thereby centriole symmetry is unclear. Here we show that Leishmania major SAS-6 crystallizes as a 9-fold symmetric cartwheel and provide the X-ray structure of this assembly at a resolution of 3.5 Å. We furthermore demonstrate that oligomerization of Leishmania SAS-6 can be inhibited by a small molecule in vitro and provide indications for its binding site. Our results firmly establish that SAS-6 can impose cartwheel symmetry on its own and indicate how this process might occur mechanistically in vivo. Importantly, our data also provide a proof-of-principle that inhibition of SAS-6 oligomerization by small molecules is feasible. DOI: http://dx.doi.org/10.7554/eLife.01812.001.
Organizational Affiliation: 
Medical Research Council Laboratory of Molecular Biology, Cambridge, United Kingdom.