Epigenetic Mechanisms and their Toxicological Significance
Genetic Toxicology, Oncogenesis, Developmental and Reproductive Toxicology
Published Online: 15 DEC 2009
Copyright © 2009 John Wiley & Sons, Ltd. All rights reserved.
General, Applied and Systems Toxicology
How to Cite
Watson, R. E. 2009. Epigenetic Mechanisms and their Toxicological Significance. General, Applied and Systems Toxicology. .
- Published Online: 15 DEC 2009
Epigenetic mechanisms are processes that exert control over gene expression without altering the DNA sequence. These mechanisms essentially work as genetic switches, turning gene expression levels on and off in response to various stimuli. Currently, DNA methylation and histone modifications (particularly histone acetylation and methylation) are the best characterized and most commonly recognized epigenetic mechanisms, although in recent years attention has turned to additional epigenetic processes such as microRNAs. Together, these mechanisms form the epigenome, a dynamic, reversible construct necessary for differentiation, tissue-specific functions, development and neurological function in eutherian mammals. However, aberrant epigenetic function may lead to untoward effects and can be a contributing factor to a variety of diseases including cancer and developmental/neurological disorders. This chapter summarizes major epigenetic mechanisms and their relevance to toxicologists, including their role in normal biological functions vs. disease-associated processes, as well as how nutrition and xenobiotic stimuli influence the epigenome. An enhanced understanding of factors that affect the epigenome can assist in both predicting undesirable toxic outcomes and in designing therapeutic strategies.
- epigenetics and toxicology;
- DNA methylation;
- histone modifications