The key role of a basic domain of histone H2B N‐terminal tail in the action of 5‐bromodeoxyuridine to induce cellular senescence

Abstract

5‐Bromodeoxyuridine (BrdU), a thymidine analogue, is an interesting reagent that modulates various biological phenomena. BrdU, upon incorporation into DNA, causes destabilized nucleosome positioning which leads to changes in heterochromatin organization and gene expression in cells. We have previously shown that BrdU effectively induces cellular senescence, a phenomenon of irreversible growth arrest in mammalian cells. Identification of the mechanism of action of BrdU would provide a novel insight into the molecular mechanisms of cellular senescence. Here, we showed that a basic domain in the histone H2B N‐terminal tail, termed the HBR (histone H2B repression) domain, is involved in the action of BrdU. Notably, deletion of the HBR domain causes destabilized nucleosome positioning and derepression of gene expression, as does BrdU. We also showed that the genes up‐regulated by BrdU significantly overlapped with those by deletion of the HBR domain, the result of which suggested that BrdU and deletion of the HBR domain act in a similar way. Furthermore, we showed that decreased HBR domain function induced cellular senescence or facilitated the induction of cellular senescence. These findings indicated that the HBR domain is crucially involved in the action of BrdU, and also suggested that disordered nucleosome organization may be involved in the induction of cellular senescence.

Upregulated expression of lamin B receptor increases cell proliferation and suppresses genomic instability: implications for cellular immortalization

“…Nuclease sensitivity assays were performed as previously described [50]. Cells were permeabilized for 5 min at room temperature with the buffer [10 m m Pipes (pH 7.0), 100 m m NaCl, 300 m m sucrose, 3 m m MgCl 2 and 0.2% Triton X‐100] and then treated with DNase I (5 U·mL −1 ) for 20 min at 37 °C in the buffer [10 m m Tris‐HCl (pH 7.5), 0.5 m m CaCl 2 , 2.5 m m MgCl 2 , 10 m m Pipes (pH7.0), 100 m m NaCl and 300 m m sucrose].…”

Cellular senescence: beneficial, harmful, and highly complex

“…." the in vitro and in vivo assessment of cellular senescence [19] Finally, we recommend reading two recently published research articles: one that describes a novel pathway from disturbed proteostasis to cellular senescence via excess ROS production and changes in mitochondria [20], and another that elucidates the role of a basic domain of histone H2B Nterminal tail in the action of 5-bromodeoxyuridine to induce cellular senescence [21,22].…”

“…We hope that this Editorial provides the readers with a comprehensive introduction to the articles featured in this Special Issue on Senescence in Ageing and Disease, and we thank the authors for their excellent contributions. We also invite our readers to look into The FEBS Journal senescence‐related articles published in the last couple of years (and which are not included in the issue); these involve, among others, an overview of the role of the extracellular matrix (ECM) of senescent cells in ageing [17], a review on targeting inter‐organelle communication, proteostasis and metabolism to eliminate senescent cells [18] and a “Guide To…” the in vitro and in vivo assessment of cellular senescence [19] Finally, we recommend reading two recently published research articles: one that describes a novel pathway from disturbed proteostasis to cellular senescence via excess ROS production and changes in mitochondria [20], and another that elucidates the role of a basic domain of histone H2B N‐terminal tail in the action of 5‐bromodeoxyuridine to induce cellular senescence [21,22].…”

Methods for Inferring Cell Cycle Parameters Using Thymidine Analogues

“…EdU, on the other hand, presents a terminal alkyne group in the same 5 position [ 22 ]. When administered, they are integrated as a totally foreign atom into replicating DNA, generating important changes in the double helical structure of this nucleic acid [ 23 ]. From these data, it is reasonable to presume that the genes that use this modified DNA are unlikely to transcribe appropriately into RNA and, eventually, the proper protein [ 11 ].…”