Notes

The detection methods and research methods of DNA and RNA modification such as Li Chengji and song chunjia were comprehensively summarized
NMN (Nicotinamide Mononucleotide),

Gao Jian provides expert evaluation, guides academic debate and expresses academic criticism. In good faith, pay attention to the scientific research ecology, disseminate scientific research experience, and promote the interaction between teachers and students.
Grapefruit sauce
So far, 17 kinds of DNA and more than 160 kinds of RNA modifications have been confirmed. The attention to the biological functions of these modifications has promoted the establishment and development of epigenetics and epigenetics. Understanding the exact location of specific deformations in the genome or transcriptome is essential for the analysis of biological function. The development of sequencing technology makes it possible to make DNA / RNA modification map, but it also leads to new problems and thoughts.
Recently, Li Chengji team of Peking University and song chunjia team of Oxford University published the invitation summary mapping the epigenetic modification software RNA in protein cell, which is currently Qualcomm DNA/
DNA fertilization plays an important role in ontogeny [1], aging [2] and cancer [3]. These modifications do not hinder the principle of Watson Crick pair, but will affect the binding of protein and DNA. Methylation of the fifth carbon atom in the mammalian genome (5-methylamine, 5-methylamine or 5mC) is the most abundant form of DNA modification, also known as the "fifth base" [1]. 5mC is catalyzed by DNA methylase DNMTs and mainly exists on CpG island. The distribution of 5mC is tissue-specific, but 70% ~ 80% of CpG islands have 5mC modification [4]. 5-hydroxymethylpyrimidine (5-hydroxymethylpyrimidine or 5hmc), also known as the sixth base, is made by oxidation of 5mC by Tet1 enzyme. 5 further oxidation of HMC produces 5-porphyrin (5FC) and 5-carboxycytosine (SCAC) 5 CAC.
Like DNA, RNA has various modifications, including all aspects of RNA metabolism. In recent years, the technology of identifying DNA / RNA modified sites by high-throughput detection has made great contributions to the research of epigenetics and epigenetics.
Identification of DNA modified sites at single base level
1. Identify 5mC components
BS SEQ (bisulfite sequencing, BS SEQ) has 99% efficiency in the conversion of bisulfite to unmethylated C. This method has the highest acceptance [5-7]. However, bisulfite treatment will produce DNA decomposition [8] , which limits its application in rare and precious samples. In addition, unmethylated C accounting for 95% of the genome becomes T, the matching genome efficiency of sequencing fragments decreases, and people's preference for coverage is higher and higher. Finally, please note that BS SEQ cannot distinguish 5mC from 5hmc.
Recently, tert azo derivative sequence (TAPs) and em-seq (em-seq) enzymaticmethylem SEQ were developed. Using tet and DNA deaminase apobec3a, the sensitivity was higher than that of BS SEQ.
Website: https://www.esthelivsale.com/products-uniqueness