CTF19 complex ensures accurate chromosome segregation by directing multiple key processes during S. cerevisiae meiosis
View/ Open
VincentenN_2015.pdf (17.88Mb)
Date
2015Item status
Restricted AccessAuthor
Vincenten, Nadine
Metadata
Abstract
The segregation of homologous chromosomes during meiosis I is a key step in the
formation of gametes. Proper segregation of homologs requires correct bipolar
spindle attachment. However, how a cell monitors and achieves this remains
unclear.
This work explores the role of the conserved Ctf19 kinetochore complex in
ensuring the accurate segregation of homologous chromosomes during meiosis I in
Saccharomyces cerevisiae. The Ctf19 complex was found to contribute to faithful
chromosome segregation during meiosis in at least three ways. First, it was found
that the Ctf19 complex is required for the localisation of both cohesin as well as the
synaptonemal complex protein, Zip1, to the centromere. Consistent with the
reduced levels of cohesin at the centromere, the disjunction of sister chromatids in
meiosis II is impaired in Ctf19 complex mutants. Second, it was shown that a
functional Ctf19 complex is important to repress crossover formation in a
pericentromeric interval, but not in a chromosome arm interval. Third, preliminary
data indicates that Ctf19 complex members are required for robust kinetochoremicrotubule
attachments. However, both the spindle assembly checkpoint and the
Aurora B-dependent error correction machinery appear to be functional in Ctf19
complex mutants. Overall, these findings demonstrate that the Ctf19 complex plays
critical roles during both meiotic prophase I and metaphase I that impinge on the
accurate segregation of homologous chromosomes during meiosis I.