Inactivation of a Human Kinetochore by Specific Targeting of Chromatin Modifiers

Citations Over TimeTop 10% of 2008 papers

Abstract

We have used a human artificial chromosome (HAC) to manipulate the epigenetic state of chromatin within an active kinetochore. The HAC has a dimeric alpha-satellite repeat containing one natural monomer with a CENP-B binding site, and one completely artificial synthetic monomer with the CENP-B box replaced by a tetracycline operator (tetO). This HAC exhibits normal kinetochore protein composition and mitotic stability. Targeting of several tet-repressor (tetR) fusions into the centromere had no effect on kinetochore function. However, altering the chromatin state to a more open configuration with the tTA transcriptional activator or to a more closed state with the tTS transcription silencer caused missegregation and loss of the HAC. tTS binding caused the loss of CENP-A, CENP-B, CENP-C, and H3K4me2 from the centromere accompanied by an accumulation of histone H3K9me3. Our results reveal that a dynamic balance between centromeric chromatin and heterochromatin is essential for vertebrate kinetochore activity.

Related Papers

• → Specification of kinetochore-forming chromatin by the histone H3 variant CENP-A(2001)291 cited
• → Rapid evolution of centromeres and centromeric/kinetochore proteins(2012)13 cited
• → Epigenetic analysis of kinetochore assembly on variant human centromeres(2001)44 cited
• → Mammalian kinetochore/centromere composition: a 50 kDa antigen is present in the mammalian kinetochore/centromere(1987)89 cited
• → Centromeres, Kinetochores and the Segregation of Chromosomes(2002)2 cited