PDS5A and TOP2B cooperate for chromatin recruitment via CTCF

Area of Science:

• Molecular Biology
• Genomics
• Cancer Research

Background:

• PDS5A (cohesin subunit) and TOP2B (DNA enzyme) interact with CTCF to regulate genome organization and gene expression.
• Mechanisms of PDS5A and TOP2B recruitment to chromatin remain unclear.

Purpose of the Study:

• Investigate the functional relationship between PDS5A and TOP2B.
• Determine their impact on genome organization and gene expression.
• Explore therapeutic implications in glioma.

Main Methods:

• Studied TOP2B-PDS5A cooperation in recruitment to CTCF-bound sites.
• Assessed PDS5A occupancy changes with active TOP2B.
• Identified a novel PDS5A-CTCF interaction region (CTCF N-terminal 95-116aa).
• Analyzed effects of CTCF(95-116aa) loss on chromatin loops and gene expression.
• Examined PDS5A and TOP2B expression in gliomas.
• Performed inducible knockdown of PDS5A in glioma cells.

Main Results:

• TOP2B and PDS5A cooperate for recruitment to CTCF-bound chromatin.
• Active TOP2B enhances PDS5A chromatin occupancy genome-wide.
• A novel CTCF interaction region (95-116aa) is essential for PDS5A-CTCF-TOP2B interaction and PDS5A enrichment.
• Loss of CTCF(95-116aa) reduces chromatin loops and dysregulates gene expression.
• PDS5A and TOP2B expression are correlated in gliomas, influencing gene expression heterogeneity.
• PDS5A knockdown reduces TOP2B occupancy and alters gene expression in glioma.
• PDS5A mediates sensitivity to TOP2 cancer drugs in glioma cells.

Conclusions:

• A novel functional interaction between PDS5A and TOP2B at chromatin boundaries clarifies genome organization mechanisms.
• This interaction impacts gene regulation and has implications for glioma therapeutics.
• PDS5A is a key mediator of sensitivity to TOP2-targeting cancer drugs in glioma.