Introduction to the Thematic Minireview Series on Epigenetics

Joel M Gottesfeld

doi:10.1074/jbc.r111.243527

Abstract

Abstract The past decade has witnessed rapid advances in our understanding of the biochemistry of "epigenetics," as exemplified by the articles in this minireview series. Epigenetics is usually defined as the study of inherited changes in phenotype of an organism or cell, caused by changes in gene expression that do not result from changes in the underlying DNA sequence. Epigenetic modifications of DNA and chromatin are essential for development of an adult organism from a fertilized egg. Each cell type in an organism expresses a distinct set of genes, but, with minor exceptions, all cells have the same DNA or genes. A fertilized egg, or zygote, changes into the numerous cell types of an organism, i.e., neurons, muscle, blood cells, etc., by activating some genes and inactivating others. Similarly, the cells within an organism respond to various stimuli by the programmed expression or repression of classes of genes.

Highlights

The enzymes responsible for both de novo DNA methylation and maintenance of methylation patterns during cell divisions are very well characterized, how these activities function in the context of cellular chromatin is less understood
The links between DNA methyltransferases and chromatin-associated proteins and post-synthetic modifications are discussed in this minireview
Stein address these mechanistic questions in their minireview entitled “Bookmarking the Genome: Maintenance of Epigenetic Information.”

Summary

Introduction

Riggs describe recent advances in our understanding of the mechanisms responsible for DNA methylation and demethylation in mammals. The enzymes responsible for both de novo DNA methylation and maintenance of methylation patterns during cell divisions are very well characterized, how these activities function in the context of cellular chromatin is less understood.

Results

Conclusion