scholarly journals Timed inhibition of CDC7 increases CRISPR-Cas9 mediated templated repair

2018 ◽  
Author(s):  
Beeke Wienert ◽  
Sharon J Feng ◽  
Melissa Locke ◽  
David N Nguyen ◽  
Stacia K Wyman ◽  
...  

Repair of double strand DNA breaks (DSBs) can result in gene disruption or precise gene modification via homology directed repair (HDR) from a templating donor DNA. During genome editing, altering cellular responses to DSBs may be an effective strategy to rebalance editing outcomes towards HDR and away from other repair pathways. To identify factors that regulate HDR from a double-stranded DNA donor (dsDonor), we utilized a pooled screen to define the consequences of thousands of individual gene knockdowns during Cas9-initiated HDR from a double strand plasmid donor. We find that templated dsDonor repair pathways are mostly genetically distinct from single strand donor DNA (ssDonor) repair but share aspects that include dependency upon the Fanconi Anemia (FA) pathway. We also identified several factors whose knockdown increases HDR and thus act as repressors of gene modification. Screening available small molecule inhibitors of these repressors revealed that the cell division cycle 7-related protein kinase (CDC7) inhibitor XL413 increases the efficiency of HDR by 2-3 fold in many contexts, including primary T-cells. XL413 stimulates HDR through cell cycle regulation, inducing an early S-phase cell cycle arrest that, to the best of our knowledge, is uncharacterized for Cas9-induced HDR. We anticipate that XL413 and other such rationally developed inhibitors will be useful tools for boosting the efficiency of gene modification.

Author(s):  
Fatma Ismail Alhmied ◽  
Ali Hassan Alammar ◽  
Bayan Mohammed Alsultan ◽  
Marooj Alshehri ◽  
Faheem Hyder Pottoo

Abstract:: Thymoquinone (TQ), the bioactive constituent of Nigella Sativa seeds is a well-known natural compound for the management of several types of cancers. The anti-cancer properties of thymoquinone are thought to be operated via intervening with various oncogenic pathways including cell cycle arrest, prevention of inflammation and oxidative stress, induction of invasion, metastasis, inhibition of angiogenesis, and apoptosis. As well as up-regulation and down-regulation of specific tumor suppressor genes and tumor promoting genes, respectively. Proliferation of various tumor cells is inhibited by TQ via induction of cell cycle arrest, disruption of the microtubule organization, and down regulating cell survival protein expression. TQ induces G1 phase cell cycle arrest in human breast cancer, colon cancer and osteosarcoma cells through inhibiting the activation of cyclin E or cyclin D and up-regulating p27and p21 a cyclin dependent kinase (Cdk) inhibitor. TQ concentration is a significant factor in targeting a particular cell cycle phase. While high concentration of TQ induced G2 phase arrest in human breast cancer (MCF-7) cells, low concentration causes S phase arrest. This review article provides mechanistic insights into the anti-cancer properties of thymoquinone.


Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 501
Author(s):  
So Hyun Park ◽  
Ji-Young Hong ◽  
Hyen Joo Park ◽  
Sang Kook Lee

Oxypeucedanin (OPD), a furocoumarin compound from Angelica dahurica (Umbelliferae), exhibits potential antiproliferative activities in human cancer cells. However, the underlying molecular mechanisms of OPD as an anticancer agent in human hepatocellular cancer cells have not been fully elucidated. Therefore, the present study investigated the antiproliferative effect of OPD in SK-Hep-1 human hepatoma cells. OPD effectively inhibited the growth of SK-Hep-1 cells. Flow cytometric analysis revealed that OPD was able to induce G2/M phase cell cycle arrest in cells. The G2/M phase cell cycle arrest by OPD was associated with the downregulation of the checkpoint proteins cyclin B1, cyclin E, cdc2, and cdc25c, and the up-regulation of p-chk1 (Ser345) expression. The growth-inhibitory activity of OPD against hepatoma cells was found to be p53-dependent. The p53-expressing cells (SK-Hep-1 and HepG2) were sensitive, but p53-null cells (Hep3B) were insensitive to the antiproliferative activity of OPD. OPD also activated the expression of p53, and thus leading to the induction of MDM2 and p21, which indicates that the antiproliferative activity of OPD is in part correlated with the modulation of p53 in cancer cells. In addition, the combination of OPD with gemcitabine showed synergistic growth-inhibitory activity in SK-Hep-1 cells. These findings suggest that the anti-proliferative activity of OPD may be highly associated with the induction of G2/M phase cell cycle arrest and upregulation of the p53/MDM2/p21 axis in SK-HEP-1 hepatoma cells.


DNA Repair ◽  
2021 ◽  
Vol 98 ◽  
pp. 103047
Author(s):  
Fatemeh Sadoughi ◽  
Jamal Hallajzadeh ◽  
Zatollah Asemi ◽  
Mohammad Ali Mansournia ◽  
Forough Alemi ◽  
...  

2012 ◽  
Vol 33 (12) ◽  
pp. 1500-1505 ◽  
Author(s):  
Yu Sun ◽  
Shusheng Tang ◽  
Xi Jin ◽  
Chaoming Zhang ◽  
Wenxia Zhao ◽  
...  

Genetics ◽  
2003 ◽  
Vol 164 (1) ◽  
pp. 323-334
Author(s):  
S B Preuss ◽  
A B Britt

Abstract Although it is well established that plant seeds treated with high doses of gamma radiation arrest development as seedlings, the cause of this arrest is unknown. The uvh1 mutant of Arabidopsis is defective in a homolog of the human repair endonuclease XPF, and uvh1 mutants are sensitive to both the toxic effects of UV and the cytostatic effects of gamma radiation. Here we find that gamma irradiation of uvh1 plants specifically triggers a G2-phase cell cycle arrest. Mutants, termed suppressor of gamma (sog), that suppress this radiation-induced arrest and proceed through the cell cycle unimpeded were recovered in the uvh1 background; the resulting irradiated plants are genetically unstable. The sog mutations fall into two complementation groups. They are second-site suppressors of the uvh1 mutant's sensitivity to gamma radiation but do not affect the susceptibility of the plant to UV radiation. In addition to rendering the plants resistant to the growth inhibitory effects of gamma radiation, the sog1 mutation affects the proper development of the pollen tetrad, suggesting that SOG1 might also play a role in the regulation of cell cycle progression during meiosis.


Biomolecules ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 302 ◽  
Author(s):  
Xin Zhang ◽  
Yao Qin ◽  
Zhaohai Pan ◽  
Minjing Li ◽  
Xiaona Liu ◽  
...  

The main chemical component of cannabis, cannabidiol (CBD), has been shown to have antitumor properties. The present study examined the in vitro effects of CBD on human gastric cancer SGC-7901 cells. We found that CBD significantly inhibited the proliferation and colony formation of SGC-7901 cells. Further investigation showed that CBD significantly upregulated ataxia telangiectasia-mutated gene (ATM) and p53 protein expression and downregulated p21 protein expression in SGC-7901 cells, which subsequently inhibited the levels of CDK2 and cyclin E, thereby resulting in cell cycle arrest at the G0–G1 phase. In addition, CBD significantly increased Bax expression levels, decreased Bcl-2 expression levels and mitochondrial membrane potential, and then upregulated the levels of cleaved caspase-3 and cleaved caspase-9, thereby inducing apoptosis in SGC-7901 cells. Finally, we found that intracellular reactive oxygen species (ROS) increased after CBD treatment. These results indicated that CBD could induce G0–G1 phase cell cycle arrest and apoptosis by increasing ROS production, leading to the inhibition of SGC-7901 cell proliferation, thereby suggesting that CBD may have therapeutic effects on gastric cancer.


2010 ◽  
Vol 84 (24) ◽  
pp. 12832-12840 ◽  
Author(s):  
Yuan He ◽  
Ke Xu ◽  
Bjoern Keiner ◽  
Jianfang Zhou ◽  
Volker Czudai ◽  
...  

ABSTRACT Many viruses interact with the host cell division cycle to favor their own growth. In this study, we examined the ability of influenza A virus to manipulate cell cycle progression. Our results show that influenza A virus A/WSN/33 (H1N1) replication results in G0/G1-phase accumulation of infected cells and that this accumulation is caused by the prevention of cell cycle entry from G0/G1 phase into S phase. Consistent with the G0/G1-phase accumulation, the amount of hyperphosphorylated retinoblastoma protein, a necessary active form for cell cycle progression through late G1 into S phase, decreased after infection with A/WSN/33 (H1N1) virus. In addition, other key molecules in the regulation of the cell cycle, such as p21, cyclin E, and cyclin D1, were also changed and showed a pattern of G0/G1-phase cell cycle arrest. It is interesting that increased viral protein expression and progeny virus production in cells synchronized in the G0/G1 phase were observed compared to those in either unsynchronized cells or cells synchronized in the G2/M phase. G0/G1-phase cell cycle arrest is likely a common strategy, since the effect was also observed in other strains, such as H3N2, H9N2, PR8 H1N1, and pandemic swine H1N1 viruses. These findings, in all, suggest that influenza A virus may provide favorable conditions for viral protein accumulation and virus production by inducing a G0/G1-phase cell cycle arrest in infected cells.


2022 ◽  
Author(s):  
Selvaraj Shyamsivappan ◽  
Raju Vivek ◽  
Thangaraj Suresh ◽  
Palanivel Naveen ◽  
Kaviyarasu Adhigaman ◽  
...  

A progression of new N-(3'-acetyl-8-nitro-2,3-dihydro-1H,3'H-spiro[quinoline-4,2'-[1,3,4]thiadiazol]-5'-yl) acetamide derivatives were synthesized from potent 8-nitro quinoline-thiosemicarbazones. The synthesized compounds were characterized by different spectroscopic studies and single X-ray crystallographic studies. The compounds were...


Sign in / Sign up

Export Citation Format

Share Document