Spatiotemporal Dynamics of H2AX Phosphorylation in Immediate Response to DNA Double-strand Breaks
Year: 2023
Type: dissertation
Abstract: DNA double-strand break (DSB) can result in genomic instability and might lead to diseases.In response to DSB, phosphorylation of the histone H2AX (γ-H2AX) by ataxia telangiectasia-mutated (ATM), ataxia telangiectasia and Rad3-related (ATR), and DNA-dependent protein kinase (DNA-PK) occurs as DNA damage signaling and can be a platform for binding of other DNA repair proteins.Here, the immediate-early dynamics of γ-H2AX was detected by using the fluorescently labeled specific antigen-binding fragments (Fabs) against γ-H2AX in time-lapse, live-cell imaging.The results indicate that DNA-PK was the essential kinase for the early γ-H2AX, while ATM was dispensable.Histone H4 lysine 16 acetylation (H4K16ac) by MOF might have a role during the DSB and its effect was examined.MOF-knockdown cells revealed that MOF did not affect the immediate-early dynamics of γ-H2AX, but disturbed the accumulation of ATM.By using the permeabilization cell assay, DNA-PK was found to be diffuses freely, while ATM was repeatedly bind and unbind from the chromatin.These results imply that ATM and DNA-PK have both redundant and non-overlapping functions during DSB.
Authors: Trakarnphornsombat, Watanya, Trakarnphornsombat, Watanya
Language: English
Topic: DNA Repair Mechanisms
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7006078568