Methylation and all that
Mammals use methylation for the heritable silencing of retrotransposons and imprinted genes and for the inactivation of the X chromosome in females.
The establishment of patterns of DNA methylation during gametogenesis depends upon DNMT3L, an enzymatically inactive regulatory factor that is related in sequence to the DNA methyltransferase DNMT3A and DNMT3B. DNMT3L interacts with the end of a histone H3 which in turn is inhibited by methylation of the histone H3.
Histone methylation is central for regulating chromatin structure, gene transcription and the epigenetic state of the cell.
This is not obscure yawn material but has significance in
1.this is how the heritable factors held in DNA are controlled, and the role of the proteins histones.
2. Methylation may well be dependent upon dietary elements , folic acid, vitamin B12 comes to mind. Clearly this is a guess but this is fascinating
Ooi et al DNMT3L ( 2007 ) connects unmethylated lysine 4 of histone H3 to de novo methylation of DNA. Nature vol 448, 714-717
Lan et al ( 2007 ) Recognition of unmethylated histone H3 lysine 4 links BHC80 to LSD1-medaited gene expression. Nature vol 448, 718-722
- Martin Eastwood