Epigenetics Flashcards

Flashcards on Epigenetics

Transcription

Synthesis of RNA complementary to one strand of a DNA segment.

Processing

In the nucleus of eukaryotic cells, the RNA usually undergoes chemical modification.

Translation

The processed RNA molecule is used to specify the order in which amino acids are joined together to form a polypeptide chain.

Enhancers

DNA sequence that can be far away from gene that improves or represses the basal level of transcription and may be located either 5′ or 3′ to the transcription start site

Epigenetics

Changes in gene function that are mitotically and/or meiotically heritable and that do not entail a change in DNA sequence

Epigenetic phenomena

Heritable self-perpetuating changes in gene expression not caused by base pair sequence changes

Histone molecules

Approximately 160 bp of DNA wrap twice around core of eight histones

Histone acetyltransferases

Add acetyl groups to histone tails, prevents close packing of nucleosomes, favors expression of genes in euchromatin

Histone methyltransferases

Add methyl groups to histone tails and the effect depends on specific amino acid modified

PRE (Polycomb response element)

Cis-acting DNA sequence that binds repressors that recruit the PRC2 co- repressor complex

DNA methylation

A methyl group is added to the cytosine base in a 5′ CpG 3′ dinucleotide by DNA methyl transferases (DNMTs)

CpG island

Cis-acting transcriptional regulatory element rich in CpG dinucleotides that is found upstream of some eukaryotic genes

Genomic imprinting

Phenomenon in which expression of an allele depends on the parent that transmits it

Insulators

Regulatory elements that establish independent domains of transcriptional activity within eukaryotic genomes

Retrotransposon

A transposable element that undergoes transposition from one place to another in the genome of a cell by forming an intermediate RNA transcript from which a copy of the DNA of the transposable element is made using a reverse transcriptase and inserted into the genome at a new location

ATAC-seq

Stands for transposase-accessible chromatin sequencing. Chromatin is isolated from a tissue of choice and DNA is fragmented using a Tn5 transposase and adapters are added simultaneously