IJMS, Vol. 19, Pages 1917: The Roles of DNA Topoisomerase IIβ in Transcription
International Journal of Molecular Sciences doi: 10.3390/ijms19071917
Type IIA topoisomerases allow DNA double helical strands to pass through each other by generating transient DNA double strand breaks &beta;DSBs), and in so doing, resolve torsional strain that accumulates during transcription, DNA replication, chromosome condensation, chromosome segregation and recombination. Whereas most eukaryotes possess a single type IIA enzyme, vertebrates possess two distinct type IIA topoisomerases, Topo II&alpha; and Topo II&beta;. Although the roles of Topo II&alpha;, especially in the context of chromosome condensation and segregation, have been well-studied, the roles of Topo II&beta; are only beginning to be illuminated. This review begins with a summary of the initial studies surrounding the discovery and characterization of Topo II&beta; and then focuses on the insights gained from more recent studies that have elaborated important functions for Topo II&beta; in transcriptional regulation.