Differential regulation of cancer progression by CDK4/6 plays a central role in DNA replication and repair pathways

2020 ◽  
pp. canres.2121.2020
Author(s):  
Meiou Dai ◽  
Julien Boudreault ◽  
Ni Wang ◽  
Sophie Poulet ◽  
Girija Daliah ◽  
...  
2005 ◽  
Vol 79 (11) ◽  
pp. 6664-6673 ◽  
Author(s):  
Travis H. Stracker ◽  
Darwin V. Lee ◽  
Christian T. Carson ◽  
Felipe D. Araujo ◽  
David A. Ornelles ◽  
...  

ABSTRACT The early transcriptional region 4 (E4) of adenovirus type 5 (Ad5) encodes gene products that modulate splicing, apoptosis, transcription, DNA replication, and repair pathways. Viruses lacking both E4orf3 and E4orf6 have a severe replication defect, partially characterized by the formation of genome concatemers. Concatemer formation is dependent upon the cellular Mre11 complex and is prevented by both the E4orf3 and E4orf6 proteins. The Mre11/Rad50/Nbs1 proteins are targeted for proteasome-mediated degradation by the Ad5 viral E1b55K/E4orf6 complex. The expression of Ad5 E4orf3 causes a redistribution of Mre11 complex members and results in their exclusion from viral replication centers. For this study, we further analyzed the interactions of E4 proteins from different adenovirus serotypes with the Mre11 complex. Analyses of infections with serotypes Ad4 and Ad12 demonstrated that the degradation of Mre11/Rad50/Nbs1 proteins is a conserved feature of the E1b55K/E4orf6 complex. Surprisingly, Nbs1 and Rad50 were localized to the replication centers of both Ad4 and Ad12 viruses prior to Mre11 complex degradation. The transfection of expression vectors for the E4orf3 proteins of Ad4 and Ad12 did not alter the localization of Mre11 complex members. The E4orf3 proteins of Ad4 and Ad12 also failed to complement defects in both concatemer formation and late protein production of a virus with a deletion of E4. These results reveal surprising differences among the highly conserved E4orf3 proteins from different serotypes in the ability to disrupt the Mre11 complex.


Open Biology ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 200293
Author(s):  
Patricia Pérez-Arnaiz ◽  
Ambika Dattani ◽  
Victoria Smith ◽  
Thorsten Allers

The tree of life shows the relationship between all organisms based on their common ancestry. Until 1977, it comprised two major branches: prokaryotes and eukaryotes. Work by Carl Woese and other microbiologists led to the recategorization of prokaryotes and the proposal of three primary domains: Eukarya, Bacteria and Archaea. Microbiological, genetic and biochemical techniques were then needed to study the third domain of life. Haloferax volcanii , a halophilic species belonging to the phylum Euryarchaeota, has provided many useful tools to study Archaea, including easy culturing methods, genetic manipulation and phenotypic screening. This review will focus on DNA replication and DNA repair pathways in H. volcanii , how this work has advanced our knowledge of archaeal cellular biology, and how it may deepen our understanding of bacterial and eukaryotic processes.


2021 ◽  
Vol 4 (9) ◽  
pp. e202101138
Author(s):  
Kenji Shimada ◽  
Monika Tsai-Pflugfelder ◽  
Niloofar Davoodi Vijeh Motlagh ◽  
Neda Delgoshaie ◽  
Jeannette Fuchs ◽  
...  

DNA polymerase δ, which contains the catalytic subunit, Pol3, Pol31, and Pol32, contributes both to DNA replication and repair. The deletion of pol31 is lethal, and compromising the Pol3–Pol31 interaction domains confers hypersensitivity to cold, hydroxyurea (HU), and methyl methanesulfonate, phenocopying pol32Δ. We have identified alanine-substitutions in pol31 that suppress these deficiencies in pol32Δ cells. We characterize two mutants, pol31-T415A and pol31-W417A, which map to a solvent-exposed loop that mediates Pol31–Pol3 and Pol31–Rev3 interactions. The pol31-T415A substitution compromises binding to the Pol3 CysB domain, whereas Pol31-W417A improves it. Importantly, loss of Pol32, such as pol31-T415A, leads to reduced Pol3 and Pol31 protein levels, which are restored by pol31-W417A. The mutations have differential effects on recovery from acute HU, break-induced replication and trans-lesion synthesis repair pathways. Unlike trans-lesion synthesis and growth on HU, the loss of break-induced replication in pol32Δ cells is not restored by pol31-W417A, highlighting pathway-specific roles for Pol32 in fork-related repair. Intriguingly, CHIP analyses of replication forks on HU showed that pol32Δ and pol31-T415A indirectly destabilize DNA pol α and pol ε at stalled forks.


Genes ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 342
Author(s):  
Lihi Gershon ◽  
Martin Kupiec

Acetylation on lysine 56 of histone H3 of the yeast Saccharomyces cerevisiae has been implicated in many cellular processes that affect genome stability. Despite being the object of much research, the complete scope of the roles played by K56 acetylation is not fully understood even today. The acetylation is put in place at the S-phase of the cell cycle, in order to flag newly synthesized histones that are incorporated during DNA replication. The signal is removed by two redundant deacetylases, Hst3 and Hst4, at the entry to G2/M phase. Its crucial location, at the entry and exit points of the DNA into and out of the nucleosome, makes this a central modification, and dictates that if acetylation and deacetylation are not well concerted and executed in a timely fashion, severe genomic instability arises. In this review, we explore the wealth of information available on the many roles played by H3K56 acetylation and the deacetylases Hst3 and Hst4 in DNA replication and repair.


Cancers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1289 ◽  
Author(s):  
Xing Bian ◽  
Wenchu Lin

Small cell lung cancer (SCLC), accounting for about 15% of all cases of lung cancer worldwide, is the most lethal form of lung cancer. Despite an initially high response rate of SCLC to standard treatment, almost all patients are invariably relapsed within one year. Effective therapeutic strategies are urgently needed to improve clinical outcomes. Replication stress is a hallmark of SCLC due to several intrinsic factors. As a consequence, constitutive activation of the replication stress response (RSR) pathway and DNA damage repair system is involved in counteracting this genotoxic stress. Therefore, therapeutic targeting of such RSR and DNA damage repair pathways will be likely to kill SCLC cells preferentially and may be exploited in improving chemotherapeutic efficiency through interfering with DNA replication to exert their functions. Here, we summarize potentially valuable targets involved in the RSR and DNA damage repair pathways, rationales for targeting them in SCLC treatment and ongoing clinical trials, as well as possible predictive biomarkers for patient selection in the management of SCLC.


Genes ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 416 ◽  
Author(s):  
Dea Slade

DNA replication and repair are essential cellular processes that ensure genome duplication and safeguard the genome from deleterious mutations. Both processes utilize an abundance of enzymatic functions that need to be tightly regulated to ensure dynamic exchange of DNA replication and repair factors. Proliferating cell nuclear antigen (PCNA) is the major coordinator of faithful and processive replication and DNA repair at replication forks. Post-translational modifications of PCNA, ubiquitination and acetylation in particular, regulate the dynamics of PCNA-protein interactions. Proliferating cell nuclear antigen (PCNA) monoubiquitination elicits ‘polymerase switching’, whereby stalled replicative polymerase is replaced with a specialized polymerase, while PCNA acetylation may reduce the processivity of replicative polymerases to promote homologous recombination-dependent repair. While regulatory functions of PCNA ubiquitination and acetylation have been well established, the regulation of PCNA-binding proteins remains underexplored. Considering the vast number of PCNA-binding proteins, many of which have similar PCNA binding affinities, the question arises as to the regulation of the strength and sequence of their binding to PCNA. Here I provide an overview of post-translational modifications on both PCNA and PCNA-interacting proteins and discuss their relevance for the regulation of the dynamic processes of DNA replication and repair.


BMC Genomics ◽  
2018 ◽  
Vol 19 (1) ◽  
Author(s):  
Justin Gibbons ◽  
Katrina A. Button-Simons ◽  
Swamy R. Adapa ◽  
Suzanne Li ◽  
Maxwell Pietsch ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document