Roles for nutrients in epigenetic events.
The field of epigenetics is the study of modifications of DNA and DNA-binding proteins that alter the structure of chromatin without altering the nucleotide sequence of DNA; some of these modifications may be associated with heritable changes in gene function. Nutrients play essential roles in the following epigenetic events. First, folate participates in the generation of S-adenosylmethionine, which acts as a methyl donor in the methylation of cytosines in DNA; methylation of cytosines is associated with gene silencing. Second, covalent attachment of biotin to histones (DNA-binding proteins) plays a role in gene silencing and in the cellular response to DNA damage. Third, tryptophan and niacin are converted to nicotinamide adenine dinucleotide, which is a substrate for poly(ADP-ribosylation) of histones and other DNA-binding proteins; poly(ADP-ribosylation) of these proteins participates in DNA repair and apoptosis. Here we present a novel procedure to map nutrient-dependent epigenetic marks in the entire genomes of any given species: the combined use of chromatin immunoprecipitation assays and DNA microarrays. This procedure is also an excellent tool to map the enzymes that mediate modifications of DNA and DNA-binding proteins in chromatin. Given the tremendous opportunities offered by the combined use of chromatin immunoprecipitation assays and DNA microarrays, the nutrition community can expect seeing a surge of information related to roles for nutrients in epigenetic events.
Oommen
Anna M
AM
Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, NE 68583-0806, USA.
Griffin
Jacob B
JB
Sarath
Gautam
G
Zempleni
Janos
J
D001483:Base Sequence; D019921:Biotinylation; D002843:Chromatin / Q000648:ultrastructure; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D019175:DNA Methylation; D055614:Genetic Phenomena; D006657:Histones / Q000378:metabolism; D007163:Immunosorbent Techniques; D009747:Nutritional Physiological Phenomena; D020411:Oligonucleotide Array Sequence Analysis; D011064:Poly Adenosine Diphosphate Ribose / Q000378:metabolism
D002843:Chromatin; D006657:Histones; D011064:Poly Adenosine Diphosphate Ribose; D004247:DNA