Research Progress in the Structural and Functional Analysis of Mammalian DNA Methyltransferase DNMT1 and DNMT3

doi:10.13560/j.cnki.biotech.bull.1985.2021-1589

Abstract

Abstract:

The DNA methyltransferases are an important protein family involved in epigenetic modification,and DNMT1,DNMT2,DNMT3A,DNMT3B and DNMT3L are the main members in mammalian. Particularly,the methyl group are transferred to the fifth carbon atom of cytosine catalyzed by DNMT1,DNMT3A and DNMT3B,which are involved in numerous biological processes of early embryonic development,germ cell development,learning and memory,and disease occurrence. In recent years,with the development of the study on the DNA methylation,the mechanism of DNA methyltransferases has attracted extensive attention from scientists. In this paper,the structural characteristics of mammalian DNA methyltransferases,the dynamic regulation of mammalian DNA methylation,and the role of DNA methyltransferases in ontogeny and disease occurrence are reviewed.

Key words: DNA methyltransferases, DNA methylation, structural characteristics, ontogeny, disease occurrence

WANG Chen-chen, ZHANG Fan-li, CHEN Pei-qi, WENG Si-yao, WANG Hui-fang, CUI Xiao-juan. Research Progress in the Structural and Functional Analysis of Mammalian DNA Methyltransferase DNMT1 and DNMT3[J]. Biotechnology Bulletin, 2022, 38(7): 31-39.

Figures/Tables 3

Fig.1 Conserved domains of mouse DNMTs protein family

Fig. 2 Establishment and maintenance of DNA methylation patterns

Fig. 3 Dynamic regulation of DNA methylation DNA methylation is established and maintained by DNMTs in mammalian. There are two pathways for DNA demethylation：1）passive dilution,i.e.,DNA replication or loss of enzymes participating in the dynamic regulation of DNA methylation may be involved in DNA demethylation;2）active demethylation,i.e.,TETs are involved in active DNA demethylation,which are successively oxidize 5mC to 5hmC,5fC and 5caC. Under the action of thymine DNA Glycosylase（TDG）,5fC and 5caC participate in the base excision repair（BER）pathway,converted to unmodified cytosine eventually

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