1. Eukaryotic Gene Organization & Control
AP Biology
Chapter 16.3/18

2. Being prokaryotic is easy
Not much DNA
One cell
Boring life

3. Being eukaryotic is hard
DNA is longer – need organization
Multicellular – every cell is different
Each cell is a specialist

4. Organization of Eukaryotic Genomes

5. Cell Differentiation
Remember you were originally one cell, with one strand of DNA.
Now you are trillions of cells, 200 different kinds of cells
Expressing different genes at different times is how you got to be you!
Hox genes

6. Eukaryotes have many different modes of control over gene expression AT ALL STEPS IN THE DIAGRAM

7. Gene Expression in Eukaryotes
physical availability of genes
due to DNA packing
consisting of nucleosomes, 30-nm chromatin fibers, looped domains
structural or chemical changes
such as
methylation, amplification
transcriptional control
transcription factors, enhancer and promoter, hormones and other chemical signals
post-transcriptional control
RNA processing
translational control
initiation factors or repressors
post-translational control
cleavage, chemical additions, degradation