Tweaking cartwheel and centriole symmetry by rational SAS-6 engineering

Jamina — Thu, 22 Oct 2015 08:49:50 +0000

Talk 2 of the day, by Michel STEINMETZ from the Paul Scherrer Institute, Department of Chemistry and Biology, Laboratory of Biomolecular Research, Villigen CH, presents studies on how SAS-6 engineering effects Cartwheel and centriole symmetry

In most species newly formed centrioles are organized around a 9-fold symmetric ‘cartwheel’ structure established by protein SAS-6
They challenged the Scaffold model, that postulates cartwheel is formed first and dictates the assembly of 9 fold symmetric microtubule wall
To do that experiments were performed to challenge this master role of the cartwheel by mutating SAS-6 to change cartwheel symmetry
The oligomers formed by various SAS-6 mutants were characterized in vitro using a combination of biophysical and structural methods, and the impact on symmetry changing mutations on cartwheels was assessed in Chlamydomonas and human cells
Independent model: Their findings reveal that cartwheel and microtubule wall operate in an independent manner to establish the 9-fold symmetric architecture of centrioles.

Reconstituting mitotic spindle organization in artificial confinement

Jamina — Thu, 22 Oct 2015 08:14:25 +0000

The first talk of the day, by Marileen Dogterom from the Department of Bionanoscience in the Kavli Institute of Nanoscience, Delft University of Technology, NL, is about Reconstituting Mitotic Spindle organization

Different experiments in artificial confinement on microtubule dynamics, their pushing and pulling forces.
Independent experiments observing the effect on mitotic spindle organization of Dynein, ACE 1 and others, show how microtubule organization and tubulin change when adding or removing them.

CRG Symposium 2015 » microtubule organization

Tweaking cartwheel and centriole symmetry by rational SAS-6 engineering

Reconstituting mitotic spindle organization in artificial confinement