The yeast DASH complex forms closed rings on microtubules.
The Saccharomyces cerevisiae DASH complex is an essential microtubule-binding component of the kinetochore. We coexpressed all ten subunits of this assembly in Escherichia coli and purified a single complex, a approximately 210-kDa heterodecamer with an apparent stoichiometry of one copy of each subunit. The hydrodynamic properties of the recombinant assembly are indistinguishable from those of the native complex in yeast extracts. The structure of DASH alone and bound to microtubules was visualized by EM. The free heterodecamer is relatively globular. In the presence of microtubules, DASH oligomerizes to form rings and paired helices that encircle the microtubules. We discuss potential roles for such collar-like structures in maintaining microtubule attachment and spindle integrity during chromosome segregation.
Miranda
J J L
JJ
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
De Wulf
Peter
P
Sorger
Peter K
PK
Harrison
Stephen C
SC
D020090:Chromosome Segregation; D018386:Kinetochores / Q000737:chemistry* / Q000378:metabolism*; D008854:Microscopy, Electron; D008870:Microtubules / Q000235:genetics / Q000378:metabolism*; D046912:Multiprotein Complexes / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
D046912:Multiprotein Complexes; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins