Deciphering the Role of Aft1p in Chromosome Stability

Abstract

The Saccharomyces cerevisiae iron-responsive transcription factor, Aft1p, has a well established role in regulating iron homeostasis through the transcriptional induction of iron-regulon genes. However, recent studies have implicated Aft1p in other cellular processes independent of iron-regulation such as chromosome stability. In addition, chromosome spreads and two-hybrid data suggest that Aft1p interacts with and co-localizes with kinetochore proteins, however the cellular implications of this have not been established. Here, we demonstrate that Aft1p associates with the kinetochore complex through Iml3p. Furthermore, we show that Aft1p, like Iml3p, is required for the increased association of cohesin with the pericentromere and that aft1Δ cells display sister chromatid cohesion defects in both mitosis and meiosis. Our work defines a new role for Aft1p in the sister chromatid cohesion pathway.