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Flashcards in Epigenetics Deck (10)
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1
Q

A change in phenotype that does not result from a change in the sequence of the gene.

  • caused by a mechanism other than mutation
  • Change is heritable
A

Epigenetics

2
Q

Signal received—> chromatin changed without changing DNA sequence
*Not all genes are expressed at any given time

A

Epigenators

3
Q

The interplay between DNA methylation and histone acetylation, and RNAi to completely repress expression of genes
-CpG island is unmethylated (allows for txn machinery to bind) —–>CpG island methylated (physically blocks txn machinery from binding)

A

Gene silencing

4
Q

Is reversible, but more permanent than not

-Sometimes methylation recruits histone deacytlases to modify histone tails

A

Gene Silencing

5
Q
  • Done in response to signals not spontaneous
  • Big insulator proteins stop processes
  • Packing pattern is heritable
A

Histone Tail Modification

6
Q
  • Transfer acetyl groups to histone tails, masking their (+) charges
  • Relaxes histone and allows txn machinery to get in
A

Histone acetyl transferases (HATS)

7
Q
  • Recruited by DNA methylation

- Reverses histone acetyl transferase activity

A

Histone Deactylases

8
Q
Regulatory RNAs control target mRNA degradation
Done by:
microRNA (miRNA)
short-interfering RNA (siRNA)
-Used:
  *during development
  *immune system of cell against viruses
A

RNA interference (RNAi)

9
Q

Protein that picks up shRNA because it recognizes it

A

RISC (RNA interference silencing complex)

10
Q

(In nucleus) miRNA—>transcribed—>miRNA transcript—>processed—(outside of nucleus)–>short hairpin RNA (shRNA)—>processed—>RISC picks up shRNA—>binds to target mRNA—–>RISC cuts mRNA—->mRNA degraded by exonuclease activity

A

Process of RNA interference