DNA-Templated Silver Nanoclusters for DNA Methylation Detection

Abstract

DNA methylation entails the covalent addition of a methyl group to C-5 position of cytosine by a family of DNA methyltransferase enzymes and has a significant role in gene regulation. Epigenetic changes such as DNA methylation of CpG islands located in the promoter region of some tumor suppressor genes are very common in human diseases such as cancer. Detection of aberrant methylation pattern could serve as an excellent diagnostic approach. It is key to develop methods for the direct and simple detection of methylated DNA or of methyltransferase activity without using antibodies, chemical modification, labeling and enzymatic treatments. In this study, we employ DNA-templated silver nanoclusters for detection of DNA methylation. This method entails use of cytosine rich DNA sequence as an effective template. By monitoring changes in fluorescence intensity, DNA methylation and DNA methyltransferase activity is detected. Upon DNA methylation, the fluorescence intensity of DNA templated Ag/NCs is decreased in a linear range when the concentration of methylated DNA is increased.

New application of bimetallic Ag/Pt nanoplates in a colorimetric biosensor for specific detection of E. coli in water

“…Furthermore, the electrostatic and intermolecular interactions of aptamer–TMB increased the substrate affinity of NPLs. As a result, the catalytic efficacy of Ag/Pt NPL was improved, resulting in a deeper blue signal ( Figure 2a , Figure 2b ) [ 32 – 33 ]. The zeta potentials of Ag/Pt NPLs, aptamer-NPLs, aptamer-NPLs coupled with E. coli , and E. coli alone were measured ( Figure 2c ).…”

Targeting the chromatin structural changes of antitumor immunity

“…During DNA methylation, cytosine protrudes from the double helix of DNA and into a gap where it can bind to enzymes. Under the catalysis of cytosine methyltransferase, the active methyl is transferred from S-adenosylmethionine to cytosine 5 to form 5mC [ 87 ]. Methylation of the gene promoter region can lead to transcriptional silence.…”

Development of General Methods for Detection of Virus by Engineering Fluorescent Silver Nanoclusters

“…Such systems efficiently avoid the sophisticated labeling and further functional process, which are favorable for sensing various analytes. For instance, DNA-AgNCs have shown excellent performance for the detection of nucleic acids (e.g., methylated DNA, miRNAs), − antibodies, bacteria, metal ions, and small molecules, in diagnostic fields.…”