TOP2B's contributions to transcription.

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Transcription is a complex process involving multiprotein complexes within chromatin.
• DNA topoisomerases modulate DNA topology during transcription by transiently breaking and rejoining DNA strands.
• DNA topoisomerase II beta (TOP2B) is one of six mammalian topoisomerases with a significant role in gene regulation.

Purpose of the Study:

• To review the role of DNA topoisomerase II beta (TOP2B) in transcription.
• To identify proteins interacting with TOP2B in the context of transcription regulation.
• To explore the impact of TOP2B absence on gene expression, particularly for long genes.

Main Methods:

• Biochemical studies to identify TOP2B-interacting proteins during ligand-regulated transcription.
• Analysis of public protein-protein interaction databases (e.g., BioGrid, IntAct).
• Comparison of publicly available ChIP-seq datasets to determine protein-DNA interaction sites.

Main Results:

• TOP2B interacts with PARP1, PRKDC, XRCC5, and XRCC6 during ligand-regulated transcription.
• Interactions with transcriptional regulators like TRIM28 and chromosome organization proteins like CTCF and RAD21 were confirmed via database analysis.
• Absence of TOP2B significantly alters transcription, with long genes being particularly affected.

Conclusions:

• TOP2B plays a critical role in regulating the transcription of developmentally important genes, especially long ones.
• TOP2B interacts with a network of proteins involved in transcription, DNA repair, and chromosome organization.
• Publicly available interaction and sequencing datasets are valuable resources for advancing models of TOP2B function in transcription.