Methylated histones on mitotic chromosomes promote topoisomerase IIα function for high fidelity chromosome segregation

Sanjana Sundararajan, Hyewon Park, Shinji Kawano, Marnie R Johansson, Bunu Lama, Tomoko Saito-Fujita, Noriko Saitoh, Alexei Arnaoutov, Mary Dasso, Zhengqiang Wang, Daniel Keifenheim, Duncan J Clarke, Yoshiaki Azuma

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

DNA Topoisomerase IIα (TopoIIα) decatenates sister chromatids, allowing their segregation in mitosis. Without the TopoIIα Strand Passage Reaction (SPR), chromosome bridges and ultra-fine DNA bridges (UFBs) arise in anaphase. The TopoIIα C-terminal domain is dispensable for the SPR in vitro but essential for mitotic functions in vivo. Here, we present evidence that the Chromatin Tether (ChT) within the CTD interacts with specific methylated nucleosomes and is crucial for high-fidelity chromosome segregation. Mutation of individual αChT residues disrupts αChT-nucleosome interaction, induces loss of segregation fidelity and reduces association of TopoIIα with chromosomes. Specific methyltransferase inhibitors reducing histone H3 or H4 methylation decreased TopoIIα at centromeres and increased segregation errors. Methyltransferase inhibition did not further increase aberrant anaphases in the ChT mutants, indicating a functional connection. The evidence reveals novel cellular regulation whereby TopoIIα specifically interacts with methylated nucleosomes via the αChT to ensure high-fidelity chromosome segregation.

Original languageEnglish (US)
Article number106743
JournaliScience
Volume26
Issue number5
DOIs
StatePublished - May 19 2023

Bibliographical note

Funding Information:
This work was supported by NIH/NIGMS, GM112793 and GM130858, then in part, by NIH/NCIR 21CA259718 and KUCC/CB pilot grant (KAN1000623) and General research funds from University of Kansas (#2144098 and #2144083). It was also supported by JSPS KAKENHI Grant Numbers JP18H05531, JP18K19310, JP20H03520 [to N.S.], and by grants from The Vehicle Racing Commemorative Foundation [to N.S.]. A. Arnaoutov and M. Dasso are supported by NIH/NICHD Intramural projects Z01 HD008954 and ZIA HD001902. SS conducted chromatin pull-down assays, created TopoII mutant replaced cell lines in Figure 3, performed UFB assay with them, optimized GSK-343 treatment conditions and performed cell-based assays in Figures 2, 5, and 6, and drafted the manuscript. HP created AID-TopoIIα cell lines and most of the TopoII mutant replaced lines, performed cell-based assays in Figures 1, 2, and S4, and acquired images. BL performed part of pull-down assays in Figures 1C and 3C, and confirmed genome editing of the cells by gPCR and western blotting for Figures S2D and S5, and part of UFB assays in Figure 5. SK established AID-TopoII line then performed initial UFB assay in Figure 5 for TopoIIα-depleted cells. DC co-designed study with YA and performed live cell imaging and analysis together with MJ and DK. TF and NS performed wndchrm analysis of the images in Figure 4. AA and MD provided original gene targeting plasmids for OsTIR and CENP-A. ZW synthesized GSK-J4 and provided important insight regarding its use in live cells. YA designed the study, supervised project, and co-wrote the manuscript with DC. The authors declare no competing financial interests. We support inclusive, diverse, and equitable conduct of research.

Funding Information:
This work was supported by NIH/ NIGMS , GM112793 and GM130858 , then in part, by NIH/ NCIR 21CA259718 and KUCC/CB pilot grant ( KAN1000623 ) and General research funds from University of Kansas (# 2144098 and # 2144083 ). It was also supported by JSPS KAKENHI Grant Numbers JP18H05531 , JP18K19310 , JP20H03520 [to N.S.], and by grants from The Vehicle Racing Commemorative Foundation [to N.S.]. A. Arnaoutov and M. Dasso are supported by NIH/ NICHD Intramural projects Z01 HD008954 and ZIA HD001902 .

Publisher Copyright:
© 2023 The Author(s)

Keywords

  • Biological sciences
  • Chromosome organization
  • Molecular biology
  • Molecular mechanism of gene regulation

PubMed: MeSH publication types

  • Journal Article

Fingerprint

Dive into the research topics of 'Methylated histones on mitotic chromosomes promote topoisomerase IIα function for high fidelity chromosome segregation'. Together they form a unique fingerprint.

Cite this