Question

Why is condensin II positioned to initiate chromosome condensation in prophase?

Answer 1

Condensin II is positioned to initiate chromosome condensation in prophase because:

1. Condensin localization in cells can influence the processes in chromosomal condensation in vertebrate cells, at least in part.
2. Condensin I is located in the cytoplasm during prophase, while condensin II binds to the chromosomes inside the nucleus.
3. Condensin II is thus poised to induce chromosomal condensation in prophase, possibly in response to cyclin A–Cdk activation.
4. Condensin I gains access to the chromosomes after the nuclear envelope is broken, and it may be critical for the cyclin B-dependent development of mitotic chromosomal structure in prometaphase and metaphase.