PICH and Cotargeted Plk1 Coordinately Maintain Prometaphase Chromosome Arm Architecture

PICH and Cotargeted Plk1 Coordinately Maintain Prometaphase Chromosome Arm Architecture

To maintain genomic stability, chromosome architecture needs to be tightly regulated as chromosomes undergo condensation during prophase and separation during anaphase, but the mechanisms remain poorly understood. Here, we show that the Plk1-binding protein PICH and Plk1 kinase coordinately maintain chromosome architecture during prometaphase. PICH knockdown results in a loss of Plk1 from the c...

PICH, a Centromere-Associated SNF2 Family ATPase, Is Regulated by Plk1 and Required for the Spindle Checkpoint

We identify PICH (Plk1-interacting checkpoint "helicase"), a member of the SNF2 ATPase family, as an interaction partner and substrate of Plk1. Following phosphorylation of PICH on the Cdk1 site T1063, Plk1 is recruited to PICH and controls its localization. Starting in prometaphase, PICH accumulates at kinetochores and inner centromeres. Moreover, it decorates threads that form during metaphas...

Upstream and downstream of PICH: Revisiting the role of the Plk1-binding protein PICH in the spindle assembly checkpoint

Regulation of Sister Chromatid Cohesion between Chromosome Arms

Sister chromatid separation in anaphase depends on the removal of cohesin complexes from chromosomes. In vertebrates, the bulk of cohesin is already removed from chromosome arms during prophase and prometaphase, whereas cohesin remains at centromeres until metaphase, when cohesin is cleaved by the protease separase. In unperturbed mitoses, arm cohesion nevertheless persists throughout metaphase...

Electrostatic force in prometaphase, metaphase, and anaphase-A chromosome motions.

Primitive cells had to divide using very few biological mechanisms. This work proposes physicochemical mechanisms, based upon nanoscale electrostatics, which explain and unify the motions of chromosomes during prometaphase, metaphase, and anaphase A. In the cytoplasmic medium that exists in biological cells, electrostatic fields are subject to strong attenuation by ionic screening, and therefor...