DNA/Chromosomes/Genomes 1 Flashcards
What is an ester bond?
RCOOR…RPOOR for the phosphodiester lineage.
DNA and protein make what structure?
Chromatin
Some translocations are normal, however, some are not balanced. What example do we have of a cancerous translocation?
Translocation of 9 and 22 forming the Philadelphia chromosome on 22.
Found in myelogenous leukemia
Explain Heterochromatin vs. Euchromatin
Heterochromatin is tightly packed and not actively transcribed.
Euchromatin is loose and is actively transcribed.
Where do nucleases cut?
Nucleases cut between nucleosomes, they cut the linker DNA.
Describe the histones octamer structure.
2 molecules each of H2A, H2B, H3, and H4.
Structural motif is called histone fold.
What is the component for chromatin regulation?
The N terminal amino acid tail extending out from the core particle undergo covalent modifications.
List the interactions between DNA and histones.
142 hydrogen bonds
Hydrophobic interactions
Salt linkages
Positive charges on Lysine and Arginine neutralize negatively charged DNA backbone.
What strand allows for genome replication?
The complimentary strand; serves as a template.
How were R strains changed to S strains and why did that matter?
S strains transformed R strains and made them pathogenic.
The process proved DNA carries genetic material.
Explain polarity?
5’ to 3’
DNA base pair in a complementary fashion = antiparallel
Pure As Gold?
Purines are adenine and guanine
Pyrimidines are big words for small ring?
One ring for Pyrimidines
Cytosine and Thymine for DNA
Uracil for RNA replaces Thymine
Why are Centromeres important and what are they associated with?
Centromeres are involved in cell division
Microtubules are attached
Treadmilliing and dynamic instability
GTP
Explain Chromosome painting?
Identifying the translocations for Philadelphia chromosome
Increased expression of BCR-ABL fusion gene
