Abstract
A model based on DNA methylation is proposed to explain the initiation and maintenance of mammalian X inactivation and certain aspects of other permanent events in eukaryotic cell differentiation. A key feature of the model is the proposal of sequence-specific DNA methylases that methylate unmethylated sites with great difficulty but easily methylate half-methylated sites. Although such enzymes have not yet been detected in eukaryotes, they are known in bacteria. An argument is presented, based on recent data on DNA-binding proteins, that DNA methylation should affect the binding of regulatory proteins. In support of the model, short reviews are included covering both mammalian X inactivation and bacterial restriction and modification enzymes.
Keywords
BiologyDNA methylationDNAMethylationEnzymeBiochemistryGeneticsGeneGene expression
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Publication Info
- Year
- 1975
- Type
- review
- Volume
- 14
- Issue
- 1
- Pages
- 9-25
- Citations
- 1318
- Access
- Closed
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Cite This
Arthur D. Riggs
(1975).
X inactivation, differentiation, and DNA methylation.
Cytogenetic and Genome Research
, 14
(1)
, 9-25.
https://doi.org/10.1159/000130315
Identifiers
- DOI
- 10.1159/000130315