Proteomic analysis of human metaphase chromosomes reveals topoisomerase II alpha as an Aurora B substrate

Proteomic analysis of human metaphase chromosomes reveals topoisomerase II alpha as an Aurora B substrate.

The essential Aurora B kinase is a chromosomal passenger protein that is required for mitotic chromosome alignment and segregation. Aurora B function is dependent on the chromosome passenger, INCENP. INCENP, in turn, requires sister chromatid cohesion for its appropriate behaviour. Relatively few substrates have been identified for Aurora B, so that the precise role it plays in controlling mito...

Proteome Analysis of Human Metaphase Chromosomes*□S

A postprophase topoisomerase II-dependent chromatid core separation step in the formation of metaphase chromosomes

Metaphase chromatids are believed to consist of loops of chromatin anchored to a central scaffold, of which a major component is the decatenatory enzyme DNA topoisomerase II. Silver impregnation selectively stains an axial element of metaphase and anaphase chromatids; but we find that in earlier stages of mitosis, silver staining reveals an initially single, folded midline structure, which sepa...

Localization of topoisomerase II in mitotic chromosomes

In the preceding article we described a polyclonal antibody that recognizes cSc-1, a major polypeptide component of the chicken mitotic chromosome scaffold. This polypeptide was shown to be chicken topoisomerase II. In the experiments described in the present article we use indirect immunofluorescence and immunoelectron microscopy to examine the distribution of topoisomerase II within intact ch...

Aurora B puts chromosomes in their place

Aurora B puts chromosomes in their place mall molecule inhibitors of Aurora B activity, characterized by Hauf et al. (page 281) and Ditchfield et al. (page 267), reveal that the mammalian kinase and its budding yeast counterpart, Ipl1, have similar functions. Without Aurora B, mistakes in kinetochore–chromosome interactions go uncorrected. Early evidence of a function for the Aurora family in c...