Incorporation of modified nucleotides into DNA, using the PCR, has allowed us to probe the influence that the exocyclic 5-methyl group of pyrimidines has on DNAse I cleavage and sequence recognition by drugs. The results show that removal of the methyl group from the major groove, made possible by substituting uridine for thymidine, allows DNAse I to cleave more readily at AT-rich regions compared to normal DNA. By contrast, addition of an extra methyl group, contrived by substituting 5-methylcytidine for normal cytidine, allows DNAse I to cleave more readily at GC-rich regions compared to normal DNA. In the cutting pattern of DNA containing both uridine and 5-methyl cytosine, we find the cleavage characteristics of both the single-substituted DNA species combined. Thus, the presence or absence of the exocyclic 5-methyl group in the major groove has a strong influence on the relative intensity of cleavage of phosphodiester bonds by DNAse I. These nucleotide substitutions can also influence the sequence-selective binding of drugs to DNA. Whereas removal of the methyl group (replacement of T with U) generally has little effect on sequence recognition by a variety of drugs, addition of a methyl group (replacement of C with M) generates new binding sites for some intercalators, namely daunomycin, DACA and SN16713.
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http://dx.doi.org/10.1016/s0167-4781(99)00188-8 | DOI Listing |
Metab Brain Dis
January 2025
Key Laboratory of Longevity and Aging-Related Disease of Chinese Ministry of Education, Center for Translational Medicine, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi, China.
2-dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) is a cyclohexanedione compound extracted from the roots of Averrhoa carambola L. Several studies have documented its beneficial effects on diabetes, Alzheimer's disease, and cancer. However, its potential neuroprotective effects on Parkinson's disease (PD) have not yet been explored.
View Article and Find Full Text PDFEpigenomics
January 2025
Cancer Research Group, School of Life Health and Chemical Sciences, The Open University UK, Milton Keynes, UK.
Background: Aggressive Variant Prostate Cancers (AVPCs) are incurable malignancies. Platinum-based chemotherapies are used for the palliative treatment of AVPC. The Polycomb Repressive Complex 2 (PRC2) promotes prostate cancer progression histone H3 Lysine 27 tri-methylation (H3K27me3).
View Article and Find Full Text PDFInt J Gynecol Cancer
January 2025
Helsinki University Hospital and University of Helsinki, Department of Obstetrics and Gynecology, Helsinki, Finland; University of Helsinki, Faculty of Medicine, Helsinki University Hospital and Research Program in Applied Tumor Genomics, Department of Pathology, Helsinki, Finland.
Objective: Endometrial carcinomas with mismatch repair deficiency (MMRd) and no specific molecular profile (NSMP) are considered to have intermediate prognoses. However, potential prognostic differences between these molecular subgroups remain unclear due to the lack of standardized control for clinicopathologic factors. This study aims to evaluate outcomes of MMRd and NSMP endometrial carcinomas across guideline-based clinicopathologic risk groups.
View Article and Find Full Text PDFJ Inflamm Res
January 2025
Department of Gastroenterology, The National Key Clinical Specialty, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, 361004, People's Republic of China.
Introduction: Crohn's disease (CD) is a chronic inflammatory condition of the intestines with a rising global incidence. Traditional diagnostic and therapeutic methods have limitations, necessitating the exploration of more effective strategies.
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Phys Chem Chem Phys
January 2025
Department of Chemistry and Biomolecular Science, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan.
Control of the formation of liquid crystalline 3̄ gyroid phases and their nanostructures is critical to advance materials chemistry based on the structural feature of three-dimensional helical networks. Here, we present that introducing methyl side-group(s) and slight non-symmetry into aryloyl-hydrazine-based molecules is unexpectedly crucial for their formation and can be a new design strategy through tuning intermolecular interactions: the two chemical modifications in the core portion of the chain-core-chain type molecules effectively lower and extend the 3̄ phase temperature ranges with the increased twist angle between neighboring molecules along the network. The detailed analyses of the aggregation structure revealed the change in the core assembly mode from the double-layered core mode of the mother molecule (without methyl groups) to the single-layered core mode.
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