Tag: 100-200

On March 4, 2021, Zhu, Pengpeng; He, Fang; Hou, Yixuan; Tu, Gang; Li, Qiao; Jin, Ting; Zeng, Huan; Qin, Yilu; Wan, Xueying; Qiao, Yina; Qiu, Yuxiang; Teng, Yong; Liu, Manran published an article.Category: imidazoles-derivatives The title of the article was A novel hypoxic long noncoding RNA KB-1980E6.3 maintains breast cancer stem cell stemness via interacting with IGF2BP1 to facilitate c-Myc mRNA stability. And the article contained the following:

Abstract: The hostile hypoxic microenvironment takes primary responsibility for the rapid expansion of breast cancer tumors. However, the underlying mechanism is not fully understood. Here, using RNA sequencing (RNA-seq) anal., we identified a hypoxia-induced long noncoding RNA (lncRNA) KB-1980E6.3, which is aberrantly upregulated in clin. breast cancer tissues and closely correlated with poor prognosis of breast cancer patients. The enhanced lncRNA KB-1980E6.3 facilitates breast cancer stem cells (BCSCs) self-renewal and tumorigenesis under hypoxic microenvironment both in vitro and in vivo. Mechanistically, lncRNA KB-1980E6.3 recruited insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) to form a lncRNA KB-1980E6.3/IGF2BP1/c-Myc signaling axis that retained the stability of c-Myc mRNA through increasing binding of IGF2BP1 with m6A-modified c-Myc coding region instability determinant (CRD) mRNA. In conclusion, we confirm that lncRNA KB-1980E6.3 maintains the stemness of BCSCs through lncRNA KB-1980E6.3/IGF2BP1/c-Myc axis and suggest that disrupting this axis might provide a new therapeutic target for refractory hypoxic tumors. The experimental process involved the reaction of N-Methyl-7H-purin-6-amine(cas: 443-72-1).Category: imidazoles-derivatives

The Article related to hypoxia lncrnkb1980e63 breast cancer stem cell igf2bp1 cmyc transcription, Biochemical Genetics: Genomic Processes and other aspects.Category: imidazoles-derivatives

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On July 30, 2020, Sun, Tong; Wu, Zhikun; Wang, Xiufang; Wang, Yilin; Hu, Xiaoyun; Qin, Wenyan; Lu, Senxu; Xu, Dongping; Wu, Yutong; Chen, Qiuchen; Ding, Xiangyu; Guo, Hao; Li, Yalun; Wang, Yuanhe; Fu, Boshi; Yao, Weifan; Wei, Minjie; Wu, Huizhe published an article.Quality Control of N-Methyl-7H-purin-6-amine The title of the article was LNC942 promoting METTL14-mediated m6A methylation in breast cancer cell proliferation and progression. And the article contained the following:

Abstract: Increasing evidence supports that long noncoding RNAs (lncRNAs) act as master regulators involved in tumorigenesis and development at the N6-methyladenine (m6A) epigenetic modification level. However, the underlying regulatory mechanism in breast cancer (BRCA) remains elusive. Here, we unveil that LINC00942 (LNC942) exerts its functions as an oncogene in promoting METTL14-mediated m6A methylation and regulating the expression and stability of its target genes CXCR4 and CYP1B1 in BRCA initiation and progression. Specifically, LNC942 and METTL14 were significantly upregulated accompanied with the upregulation of m6A levels in BRCA cells and our included BRCA cohorts (n = 150). Functionally, LNC942 elicits potent oncogenic effects on promoting cell proliferation and colony formation and inhibiting cell apoptosis, subsequently elevating METTL14-mediated m6A methylation levels and its associated mRNA stability and protein expression of CXCR4 and CYP1B1 in BRCA cells. Mechanistically, LNC942 directly recruits METTL14 protein by harboring the specific recognize sequence (+176-+265), thereby stabilized the expression of downstream targets of LNC942 including CXCR4 and CYP1B1 through posttranscriptional m6A methylation modification in vitro and in vivo. Therefore, our results uncover a novel LNC942-METTL14-CXCR4/CYP1B1 signaling axis, which provides new targets and crosstalk m6A epigenetic modification mechanism for BRCA prevention and treatment. The experimental process involved the reaction of N-Methyl-7H-purin-6-amine(cas: 443-72-1).Quality Control of N-Methyl-7H-purin-6-amine

The Article related to lnc942 mettl14 methylation human breast cancer proliferation metastasis, Biochemical Genetics: Genomic Processes and other aspects.Quality Control of N-Methyl-7H-purin-6-amine

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On December 1, 2007, Al Mamun, Abu Amar M. published an article.COA of Formula: C6H5N3O The title of the article was Elevated expression of DNA polymerase II increases spontaneous mutagenesis in Escherichia coli. And the article contained the following:

Escherichia coli DNA polymerase II (Pol-II), encoded by the SOS-regulated polB gene, belongs to the highly conserved group B (α-like) family of “high-fidelity” DNA polymerases. Elevated expression of polB gene was recently shown to result in a significant elevation of translesion DNA synthesis at 3, N4-ethenocytosine lesion with concomitant increase in mutagenesis. Here, I show that elevated expression of Pol-II leads to an approx. 100-fold increase in spontaneous mutagenesis in a manner that is independent of SOS, umuDC, dinB, recA, uvrA and mutS functions. Cells grow slowly and filament with elevated expression of Pol-II. Introduction of carboxy terminus (“β interaction domain”) mutations in polB eliminates elevated spontaneous mutagenesis, as well as defects in cell growth and morphol., suggesting that these abilities require the interaction of Pol-II with the β processivity subunit of DNA polymerase III. Introduction of a mutation in the proofreading exo motif of polB elevates mutagenesis by a further 180-fold, suggesting that Pol-II can effectively compete with DNA polymerase III for DNA synthesis. Thus, Pol-II can contribute to spontaneous mutagenesis when its expression is elevated. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).COA of Formula: C6H5N3O

The Article related to escherichia dna polymerase ii expression motif spontaneous mutagenesis, Biochemical Genetics: Genomic Processes and other aspects.COA of Formula: C6H5N3O

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On January 29, 2006, Al Mamun, Abu Amar M.; Humayun, M. Zafri published an article.Related Products of 55662-66-3 The title of the article was Escherichia coli DNA polymerase II can efficiently bypass 3,N4-ethenocytosine lesions in vitro and in vivo. And the article contained the following:

Escherichia coli DNA polymerase II (pol-II) is a highly conserved protein that appears to have a role in replication restart, as well as in translesion synthesis across specific DNA adducts under some conditions. Here, we have investigated the effects of elevated expression of pol-II (without concomitant SOS induction) on translesion DNA synthesis and mutagenesis at 3,N 4-ethenocytosine (εC), a highly mutagenic DNA lesion induced by oxidative stress as well as by exposure to industrial chems. such as vinyl chloride. In normal cells, survival of transfected M13 single-stranded DNA bearing a single εC residue (εC-ssDNA) is about 20% of that of control DNA, with about 5% of the progeny phage bearing a mutation at the lesion site. Most mutations are C → A and C → T, with a slight predominance of transversions over transitions. In contrast, in cells expressing elevated levels of pol-II, survival of εC-ssDNA is close to 100%, with a concomitant mutation frequency of almost 99% suggesting highly efficient translesion DNA synthesis. Furthermore, an overwhelming majority of mutations at εC are C → T transitions. Purified pol-II efficiently catalyzes translesion synthesis at εC in vitro, accompanied by high levels of mutagenesis with the same specificity. These results suggest that the observed in vivo effects in pol-II over-expressing cells are due to pol-II-mediated DNA synthesis. Introduction of mutations in the carboxy terminus region (β interaction domain) of polB eliminates in vivo translesion synthesis at εC, suggesting that the ability of pol-II to compete with pol-III requires interaction with the β processivity subunit of pol-III. Thus, pol-II can compete with pol-III for translesion synthesis. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Related Products of 55662-66-3

The Article related to escherichia dna polymerase ii ethenocytosine lesion bypass mutagenesis, Biochemical Genetics: Genomic Processes and other aspects.Related Products of 55662-66-3

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

Revankar, Ganapathi R.; Robins, Roland K. published an article in 1975, the title of the article was Synthesis and biological activity of some nucleosides resembling guanosine: imidazo[1,2-a]pyrimidine nucleosides.Quality Control of 7-Chloroimidazo[1,2-a]pyrimidin-5(1H)-one And the article contains the following content:

Refluxing di-Et malonate in NaOEt with 2-aminoimidazole hemisulfate gave 49.6% 5,7-dihydroxyimidazo[1,2-a]pyrimidine, which was chlorinated with POCl3 and treated with 5% aqueous NaOH to give I. Refluxing I with NH(SiMe3)2 and (NH4)2SO4 followed by addition of tetra-O-acetyl-β-D-ribofuranose and deacetylation gave II (R = Cl) (III). Amination of III with NH3 in MeOH at 100° gave 46% II (R = NH2) which showed no in vitro antiviral activity with the RNA and DNA virus tested. The experimental process involved the reaction of 7-Chloroimidazo[1,2-a]pyrimidin-5(1H)-one(cas: 57473-33-3).Quality Control of 7-Chloroimidazo[1,2-a]pyrimidin-5(1H)-one

The Article related to imidazopyrimidine nucleoside, ribofuranosylimidazopyrimidine virucide, Carbohydrates: Nucleosides, Nucleotides and other aspects.Quality Control of 7-Chloroimidazo[1,2-a]pyrimidin-5(1H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On March 15, 2017, Chaim, Isaac A.; Gardner, Alycia; Wu, Jie; Iyama, Teruaki; Wilson, David M. III; Samson, Leona D. published an article.Computed Properties of 55662-66-3 The title of the article was A novel role for transcription-coupled nucleotide excision repair for the in vivo repair of 3,N4-ethenocytosine. And the article contained the following:

Etheno (ε) DNA base adducts are highly mutagenic lesions produced endogenously via reactions with lipid peroxidation (LPO) products. Cancer-promoting conditions, such as inflammation, can induce persistent oxidative stress and increased LPO, resulting in the accumulation of ε-adducts in different tissues. Using a recently described fluorescence multiplexed host cell reactivation assay, we show that a plasmid reporter bearing a site-specific 3,N4-ethenocytosine (εC) causes transcriptional blockage. Notably, this blockage is exacerbated in Cockayne Syndrome and xeroderma pigmentosum patient-derived lymphoblastoid and fibroblast cells. Parallel RNA-Seq expression anal. of the plasmid reporter identifies novel transcriptional mutagenesis properties of εC. Our studies reveal that beyond the known pathways, such as base excision repair, the process of transcription-coupled nucleotide excision repair plays a role in the removal of εC from the genome, and thus in the protection of cells and tissues from collateral damage induced by inflammatory responses. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Computed Properties of 55662-66-3

The Article related to transcription coupled nucleotide dna excision repair nethenocytosine, Biochemical Genetics: Genomic Processes and other aspects.Computed Properties of 55662-66-3

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On December 21, 2004, Choi, Jun-Hyuk; Pfeifer, Gerd P. published an article.COA of Formula: C6H5N3O The title of the article was DNA damage and mutations produced by chloroacetaldehyde in a CpG-methylated target gene. And the article contained the following:

Chloroacetaldehyde (CAA) is a metabolite of the human carcinogen vinyl chloride. CAA produces several types of DNA adducts including the exocyclic base adducts 3,N4-ethenocytosine, 1,N6-ethenoadenine, N2,3-ethenoguanine, and 1,N2-ethenoguanine. Adducts of CAA with 5-methylcytosine have not yet been characterized. Here the authors have analyzed the mutational spectra produced by CAA in the supF gene of the pSP189 shuttle vector when present in either an unmethylated or CpG-methylated state. The vectors were replicated in human nucleotide excision repair-deficient XP-A fibroblasts. The mutational spectra obtained with the unmethylated and methylated supF target genes were generally similar with a preponderance of C/G to T/A transitions and C/G to A/T transversions. CAA-induced DNA adducts were mapped along the supF gene by using thermostable thymine DNA glycosylase (TDG) in conjunction with ligation-mediated PCR or by a Taq polymerase stop assay. Prominent CAA-induced TDG-sensitive sites were seen at several CpG positions but were independent of methylation. Methylated CpG sites were sites of CAA-induced mutations but were not the major mutational hotspots. Taq polymerase arrest sites were observed at numerous sequence positions in the supF gene and reflected the rather broad distributions of mutations along the sequence. We conclude that methylated CpG sites are not preferential targets for chloroacetaldehyde-induced mutagenesis. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).COA of Formula: C6H5N3O

The Article related to dna damage mutation chloroacetaldehyde cpg methylation supf gene, Toxicology: Carcinogens, Mutagens, and Teratogens and other aspects.COA of Formula: C6H5N3O

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On February 3, 2009, Knutson, Charles G.; Rubinson, Emily H.; Akingbade, Dapo; Anderson, Carolyn S.; Stec, Donald F.; Petrova, Katya V.; Kozekov, Ivan D.; Guengerich, F. Peter; Rizzo, Carmelo J.; Marnett, Lawrence J. published an article.COA of Formula: C6H5N3O The title of the article was Oxidation and Glycolytic Cleavage of Etheno and Propano DNA Base Adducts. And the article contained the following:

Non-invasive strategies for the anal. of endogenous DNA damage are of interest for the purpose of monitoring genomic exposure to biol. produced chems. The authors have focused the authors’ research on the biol. processing of DNA adducts and how this may impact the observed products in biol. matrixes. Preliminary research has revealed that pyrimidopurinone DNA adducts are subject to enzymic oxidation in vitro and in vivo and that base adducts are better substrates for oxidation than the corresponding 2′-deoxynucleosides. The authors tested the possibility that structurally similar exocyclic base adducts may be good candidates for enzymic oxidation in vitro. The authors investigated the in vitro oxidation of several endogenously occurring etheno adducts [1,N2-ε-guanine (1,N2-ε-Gua), N2,3-ε-Gua, heptanone-1,N2-ε-Gua, 1,N6-ε-adenine (1,N6-ε-Ade), and 3,N4-ε-cytosine (3,N4-ε-Cyt)] and their corresponding 2′-deoxynucleosides. Both 1,N2-ε-Gua and heptanone-1,N2-ε-Gua were substrates for enzymic oxidation in rat liver cytosol; heteronuclear NMR experiments revealed that oxidation occurred on the imidazole ring of each substrate. In contrast, the partially or fully saturated pyrimidopurinone analogs [i.e., 5,6-dihydro-M1G and 1,N2-propanoguanine (PGua)] and their 2′-deoxynucleoside derivatives were not oxidized. The 2′-deoxynucleoside adducts, 1,N2-ε-dG and 1,N6-ε-dA, underwent glycolytic cleavage in rat liver cytosol. Together, these data suggest that multiple exocyclic adducts undergo oxidation and glycolytic cleavage in vitro in rat liver cytosol, in some instances in succession. These multiple pathways of biotransformation produce an array of products. Thus, the biotransformation of exocyclic adducts may lead to an addnl. class of biomarkers suitable for use in animal and human studies. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).COA of Formula: C6H5N3O

The Article related to etheno propano dna base adduct oxidation glycolytic cleavage, Toxicology: Carcinogens, Mutagens, and Teratogens and other aspects.COA of Formula: C6H5N3O

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On October 31, 1992, Kusmierek, J. T.; Singer, B. published an article.Quality Control of Imidazo[1,2-c]pyrimidin-5(6H)-one The title of the article was 1,N2-Ethenodeoxyguanosine: properties and formation in chloroacetaldehyde-treated polynucleotides and DNA. And the article contained the following:

1,N2-Etheno-2′-deoxyguanosine (1,N2-εdGuo) (I), not previously reported as a product of chloroacetaldehyde (CAA) reaction, was synthesized and characterized. Reaction of deoxyguanosine with CAA in DMF in the presence of K2CO3 led to the preparation of pure 1,N2-εdGuo with a 55% yield. PKa values are 2.2 and 9.2. The anionic form of the compound exhibits weak but defined fluorescence; the intensity is similar to that of N2,3-etheno-2′-deoxyguanosine (N2,3-εdGuo) at neutrality. The stability of the glycosyl bond of 1,N2-εdGuo (t1/2 = 2.3 h at 37°, pH 1) is 10-fold greater than of unmodified deoxyguanosine and at least 1000-fold greater than that of isomeric N2,3-εdGuo. Reaction of CAA with model polynucleotides indicates that hydrogen bonding of guanine residues in the double-stranded structures is, as expected, an important factor in the formation of 1,N2-ethenoguanine. In contrast, the formation of isomeric N2,3-ethenoguanine is relatively independent of whether the DNA is single- or double-stranded. In salmon sperm DNA, reacted with CAA at neutrality, the formation of 1,N2-ethenoguanine could be demonstrated. However, the authors find the efficiency of formation of this adduct in double-stranded DNA is lower than that of all other etheno derivatives The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Quality Control of Imidazo[1,2-c]pyrimidin-5(6H)-one

The Article related to chloroacetaldehyde ethenodeoxyguanosine polynucleotide dna, Toxicology: Carcinogens, Mutagens, and Teratogens and other aspects.Quality Control of Imidazo[1,2-c]pyrimidin-5(6H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem

On April 20, 1993, Palejwala, Vaseem A.; Rzepka, Robert W.; Humayun, M. Zafri published an article.Reference of Imidazo[1,2-c]pyrimidin-5(6H)-one The title of the article was UV irradiation of Escherichia coli modulates mutagenesis at a site-specific ethenocytosine residue on M13 DNA. Evidence for an inducible recA-independent effect. And the article contained the following:

Mutagenic action of chem. and phys. mutagens is mediated through DNA damage and subsequent misreplication at sites of unrepaired damage. Most DNA damage is noninstructive in the sense that the causative chem. modification either destroys the template information or renders it inaccessible to the DNA polymerase. Noninstructive adducts possess high genotoxicity because they stop DNA replication. Replication past noninstructive adducts is thought to depend on induced functions in addition to the regular replication machinery. In E. coli, noninstructive DNA damage leads to induction of the SOS regulon, which in turn is thought to provide the inducible functions required for replicative bypass of the lesion. Because of the absence of accessible template instruction, base incorporation opposite noninstructive lesions is inherently error-prone and results in mutagenesis. Ethenocytosine (εC), an exocyclic DNA lesion induced by carcinogens such as vinyl chloride and urethane, is a highly mutagenic, noninstructive lesion on the basis of its template characteristics in vivo and vitro. However, mutagenesis at εC does not require SOS functions, as evidenced by efficient mutagenesis in recA-deleted E. coli. Even though efficient mutagenesis in recA-deleted cells shows a lack of SOS dependence, the question remains whether SOS induction can modulate mutagenesis opposite εC. To exam. the possible contribution of SOS functions to mutagenesis at εC, an M13 duplex circular DNA mol. containing an εC residue was constructed at a unique site. The construct was transfected into nonirradiated or UV-irradiated E. coli. The frequency as well as specificity of the mutations induced under a number of conditions was determined by using a multiplex DNA sequencing technol. Without prior UV irradiation, ∼33% of the host cells show a significant increase in mutagenesis, with most of the increase accounted for by an increase in C→A transversions. Surprisingly, essentially identical effects were observed in irradiated recA-deleted cells as well as in umuC-deficient cells, suggesting that the observed UV modulation of mutagenesis is independent of the SOS pathway. These observations suggest the existence of a recA-independent UV-inducible mutagenic mechanism in E. coli. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).Reference of Imidazo[1,2-c]pyrimidin-5(6H)-one

The Article related to uv mutagenesis dna ethenocytosine site escherichia, Radiation Biochemistry: Effects In Microorganisms and other aspects.Reference of Imidazo[1,2-c]pyrimidin-5(6H)-one

Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem