title: G-quadruplex functionalized nano mesoporous silica for assay of the DNA methyltransferase activity.
abstract: The abnormal level of DNA methyltransferase (MTase) may cause the aberrant DNA methylation, which has been found being associated with a growing number of human diseases, so it is necessary to create a sensitive and selective method to detect DNA MTase activity. In this paper, a new type of DNA functionalized nano mesoporous silica (MSNs) was creatively introduced to the detection of DNA MTase activity with G-quadruplex as a lock for signal molecule to release. The method was carried out by designing a particular DNA which could fold into G-quadruplex and complement with probe DNA. Next, MSNs was prepared before blocking methylene blue (MB) by G-quadruplex. Probe DNA was then fixed on gold nanoparticles modified glass carbon electrode, and the material was able to be transferred to the surface of electrode by DNA hybridization. After methylation of DNA MTase and the cutting of restriction endonuclease, the electrode was transferred to phosphate buffer solution (pH 9.0) for the releasing of MB. The response of differential pulse voltammetry was obtained from the release of MB. Consequently, the difference of signals with or without methylation could prove the assay of M. SssI MTase activity. The results showed that the responses from MB increased linearly with the increasing of the M. SssI MTase concentrations from 0.28 to 50UmL(-1). The limit of detection was 0.28UmL(-1). In addition, Zebularine, a nucleoside analog of cytidine, was utilized for studying the inhibition activity of M. SssI MTase.
authors.affiliation: College of Chemistry and Material Science, Shandong Agricultural University, 271018 Taian, Shandong, PR China.
authors.forename: Pei
authors.initials: P
authors.lastname: Liu
authors.affiliation: College of Chemistry and Material Science, Shandong Agricultural University, 271018 Taian, Shandong, PR China.
authors.forename: Junling
authors.initials: J
authors.lastname: Pang
authors.affiliation: College of Chemistry and Material Science, Shandong Agricultural University, 271018 Taian, Shandong, PR China. Electronic address: yinhs@sdau.edu.cn.
authors.forename: Huanshun
authors.initials: H
authors.lastname: Yin
authors.affiliation: College of Chemistry and Material Science, Shandong Agricultural University, 271018 Taian, Shandong, PR China. Electronic address: ashy@sdau.edu.cn.
authors.forename: Shiyun
authors.initials: S
authors.lastname: Ai
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D003562:Cytidine / Q000031:analogs & derivatives / Q000494:pharmacology; D019175:DNA Methylation; D015257:DNA-Cytosine Methylases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D055664:Electrochemical Techniques / Q000379:methods; D057075:Enzyme Assays / Q000379:methods*; D054856:G-Quadruplexes; D006801:Humans; D057230:Limit of Detection; D008751:Methylene Blue / Q000737:chemistry; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003562:Cytidine; D012822:Silicon Dioxide; C009131:pyrimidin-2-one beta-ribofuranoside; C081573:DNA modification methylase SssI; D015257:DNA-Cytosine Methylases; D008751:Methylene Blue
keywords: DNA methylation; Differential pulse voltammetry; Methylene blue; Nano mesoporous silica