Usage Information
Abstract
Glycogen synthase kinase-3β (GSK3β) is an established regulator in the DNA double-strand break (DSB) repair pathway. Recent work by Allam et al. revealed a mechanism of DSB repair pathway choice through GSK3β-mediated, site-specific phosphorylation of the tumor suppressor p53 binding protein 1 (53BP1) at threonine 334 (T334). 53BP1 T334 phosphorylation prevented interaction between 53BP1 and its downstream functional partners, PTIP and RIF1, thereby inhibiting 53BP1-directed nonhomologous end joining (NHEJ). Additionally, 53BP1 T334 phosphorylation promoted recruitment of CtIP and RPA32 to DNA damage sites to facilitate homologous recombination (HR). In contrast with loss of 53BP1 function, a 53BP1 T334A phospho-deficient mutant accumulated aberrantly at DSBs, where it impaired end resection and suppressed HR activity. These surprising results suggest that GSK3β may select between NHEJ and HR DNA repair pathways. Additionally, these data support targeting the GSK3β/53BP1 axis to enhance PARP inhibitor efficacy in solid tumors, regardless of BRCA1 status.
Authors
Justin W. Leung, David Gius
Usage data is cumulative from November 2025 through August 2026.
| Usage | JCI | PMC |
|---|---|---|
| Text version | 1,935 | 119 |
| 528 | 29 | |
| Figure | 371 | 0 |
| Citation downloads | 230 | 0 |
| Totals | 3,064 | 148 |
| Total Views | 3,212 | |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)