DNA Methyltransferases in Mammalian Oocytes
OOCYTES: MATERNAL INFORMATION AND FUNCTIONS, cilt.63, ss.211-222, 2017 (SCI-Expanded)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 63
- Basım Tarihi: 2017
- Doi Numarası: 10.1007/978-3-319-60855-6_10
- Dergi Adı: OOCYTES: MATERNAL INFORMATION AND FUNCTIONS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, EMBASE, MEDLINE
- Sayfa Sayıları: ss.211-222
- Akdeniz Üniversitesi Adresli: Evet
Özet
Epigenetic mechanisms play important roles in properly occurring mammalian oogenesis. One of these mechanisms is DNA methylation adding a methyl group to the fifth carbon atom of the cytosine residues using S-adenosyl-L-methionine as a methyl donor. DNA methylation generally takes place at cytosine-phosphate-guanine (CpG) dinucleotide sites and rarely occurs at cytosine-phosphate-thymine (CpT), cytosine-phosphate-adenine (CpA), or cytosine-phosphate-cytosine sites, known as non-CpG sites. Basically, two different DNA methylation processes are identified: de novo methylation and maintenance methylation. While the de novo methylation functions in methylation of unmethylated DNA strands, maintenance methylation is capable of methylating hemi-methylated DNA strands following DNA replication. Both DNA methylation processes are catalyzed by special DNA methyltransferase (DNMT) enzymes. To date, five different DNMTs have been identified: DNMT1, DNMT3A, DNMT3B, DNMT3L, and DNMT2. In this chapter, we focus particularly on temporal and spatial expression of DNMTs in mammalian oocytes and granulosa cells.