Stem Cell Epigenetics (Lecture 6)

Question 1

Stem cell signaling process

Answer 1

• transcription factor expression
• nuclear structure
• epigenetics

Question 2

Core pluripotency network

Answer 2

• the stemness factors are reinforcing one another (feed-forward)
• not always transcriptional activators, sometimes they inhibit

Question 3

Activating function of oct4, klf4, sox2 (and nanog)

Answer 3

LISTEN TO RECORDING

• p300 is coactivator that recruits transcription factors to increase expression
• – add acetyl groups to histones to open them up and allow transcription factors to bind and turn on target genes

Question 4

HAT

Answer 4

increases histone acetylation and opens chromatin

Question 5

HDAC

Answer 5

• decreases histone acetylation and closes chromatin
• removes acetyl groups, allowing histones to wrap DNA tightly, deactivating genes
• recruits PcG to repress particular genes

Question 6

cMyc function

Answer 6

• multi-use transcription factor turning on proliferation regulators while inhibiting differentiation genes
• ramps up transcription and translation and promotes energy proliferation and metabolism

Question 7

H3 trimethylation

Answer 7

• off –> PcG catalyzes trimethylation of lysine 27 (H3K27me3)
• on –> Trx catalyzes trimethylation of lysine 4 (H3K4me3)