Nutrigenomics: Epigenetics Flashcards
What is Histone Acetylation?
Addition of an acetyl group. Methyl group (CH3) bound to carbonyl group
What is the effect of acetylation on histones?
Acetylation neutralizes positive charge of histone tails = less binding to negative DNA.
- DNA more accessible
- More transcription (gene activation)
What is Deacetylation?
Gene silencing
What are Sirtuins?
Protein that deacetylates histones (silencing genes). 7 different sirtuins
How are Sirtuin genes/proteins changed?
By lifestyle.
- Calorie restriction
- Exercise
- Alcohol
- Smoking
- Plant compounds
What is Resveratrol?
Phenolic compound in wine. Histone Modification
Resveratrol and Deacetylation
- Sirtuins
- Removal of acetyl group from histone
- Changes gene expression (silences)
- Linked to health and longevity in specific societies
Epigenetics
microRNA
What are microRNA?
- Made from own genes or introns (non coding regions)
- Short RNA that binds to mRNA and increases mRNA degradation
- Regulation “above”the gene but based on bases in genes (ATCH)
- Another key component of gene regulation
miRNA found in Breast Milk
- microRNAs abundant in human breast milk for the duration of breast feeding
- 442 unique premiRNAs and 602 unique miRNAs found in breast milk exosomes
- miRNAs found in mammal milk is stable at room temp and are resistant to repeated freeze cycles
- —encapsulated in exosomes
When are miRNA highest in immune support?
first 6 months of feeding
RD role with Nutrigenetics
- Translation of scientific knowledge of how diet affects individual humans
- individualized care
RD role with nutrigenomics
- translation of scientific knowledge about how diet affect gene expression
- understanding of mechanism
Types of genetic testing
- Research –> decode link between genes and disease
- Direct to consumer genetic testing –> send in DNA sample from saliva (ancestral orgins)
- Health care guided testing–> rare disease and chronic disease
Transcriptomics
study of gene expression - RNA
