Which kinase plays a crucial role in chromosome condensation?
Transformation of extended interphase chromatin into compact rod-shaped mitotic chromosomes requires condensin complexes and coordinated kinase activation. Condensin II pentamer containing SMC2, SMC4 and subunits CAP-D3, CAP-G2, CAP-H2 resides in nucleus during interphase and initiates early looping as cells enter prophase. Condensin I pentamer with CAP-D2, CAP-G, CAP-H gains access to chromosomes after nuclear envelope breakdown in prometaphase. Activation depends on mitotic kinases: CDK1-Cyclin B phosphorylates CAP-D3 Threonines and CAP-H promoting ATPase activity, Polo-like kinase 1 phospho
Ref: Hirano, Condensin Complexes Drive Chromosome Condensation, Annu Rev Cell Dev Biol 2005; Alberts et al., Chapter 17, Condensins.