The stoichiometries of kinetochores and their constituent proteins in yeast and vertebrate cells were determined using the histone H3 variant CENP-A, known as Cse4 in budding yeast, as a counting standard. One Cse4-containing nucleosome exists in the centromere (CEN) of each chromosome, so it has been assumed that each anaphase CEN/kinetochore cluster contains 32 Cse4 molecules. We report that anaphase CEN clusters instead contained approximately fourfold more Cse4 in Saccharomyces cerevisiae and ~40-fold more CENP-A (Cnp1) in Schizosaccharomyces pombe than predicted. These results suggest that the number of CENP-A molecules exceeds the number of kinetochore-microtubule (MT) attachment sites on each chromosome and that CENP-A is not the sole determinant of kinetochore assembly sites in either yeast. In addition, we show that fission yeast has enough Dam1-DASH complex for ring formation around attached MTs. The results of this study suggest the need for significant revision of existing CEN/kinetochore architectural models.
Pubmed ID: 22084306 RIS Download
Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.
Data analysis, graphing, and management application that allows users to import, manipulate, analyze data, and create customized plots. Plots include x-y probability, histogram, box, percentile, horizontal bar, stack bar, column, stack column, polar, and pie. Binned data can be exported to a histogram, step plot, or spike plot. KaleidaGraph works with Windows and Macintosh systems.
View all literature mentions