Clinical Correlates

Front 1

Telomere length decreases with with age due to adults having less telomerase. What are 4 problems caused by genetic defects of telomerase?

Back 1

Bone marrow failure; skin abnormalities, intestinal villus atrophy, lung fibrosis

Hint 1

Problems in quickly dividing cells

Front 2

A danger of taking etopside or doxorubicin

Back 2

These are cancer drugs that inhibit topoisomerase II. A side effect is that they are very toxic to any rapidly diving cells

Front 3

What causes Hutchinson-Gilford Progeria?

Back 3

Mutation in lamin A protein (one of the proteins making up nuclear lamina). Actual mechanism of disease unclear

Front 4

Tetracycline

Back 4

Inhibits aminoacyl tRNA binding

Front 5

Streptomycin

Back 5

Inhibits initiation, causes misreading of the code

Front 6

Erythromycin

Back 6

Inhibits translocation

Front 7

Chloramphenicol

Back 7

Inhibits peptidyl transferase in bacteria

Front 8

Cycloheximide

Back 8

Inhibits peptidyl transferase in humans

Front 9

This inactivates 28S section of large subunit of the ribosome by removing highly conserved adenine

Back 9

Ricin enzyme (a residue after making castor oil)

Front 10

A toxin that Inactivates eEF2 (elongation factor that does translocation)

Back 10

Dyptheria

Front 11

Part of this virus cleaves eIF4G so it can no longer function as a bRidge between the cap binding protein and the 40S subunit

Back 11

Poliomyelitis

Front 12

After CG-rich sequences are methylated, proteins such as MECP2 (methylcytosine-binding protein-2) bind to help compact and silence the gene.

An X-linked loss-of-function mutation in MECP2 causes what disease?

Back 12

Rett Syndrome -- causes dysregulated gene expression.

Males die before birth

Heterozygous females are normal at birth but have developmental regression, neuro symptoms by 6 months

Front 13

Difference between pseudogene and processed pseudogene

Back 13

Both are nonfunctional but pseudogenes are duplicated genes, mutated out of functionality.

Processed pseudogenes are integrated cDNA where the promoters have been processed out

Front 14

Misalignment during meiosis happens and creates duplicated genes lying next to each other with what mechanism?

Back 14

Illegitimate crossing over

Front 15

2 important Na+ channels

Back 15

Voltage gated:action potential generation

Nonvoltage gated: absorption of Na+ by epithelial in GI Tracy and kidneys

Front 16

3 important types of K+ channels

Back 16

Generation of resting potential in all cells (unlike Na+, electrochemical driving force for K+ tends to cause efflux of K+)

Termination of action potential in excitable cells

Homeostasis of K+ in GI and kidneys

Front 17

3 important types of K+ channels

Back 17

Generation of resting potential in all cells (unlike Na+, electrochemical driving force for K+ tends to cause efflux of K+)

Termination of action potential in excitable cells

Homeostasis of K+ in GI and kidneys

Front 18

2 important Ca+ channels

Back 18

1. Transmembrane signaling in many cells

2.generation of action potential in some excitable cells

Electrochemical driving F always favors influx of Ca+ (but it's 1000x less concentrated in cells than ECF)

Front 19

4 roles of Cl- channels

Back 19

1. Excitability CNS neurons

2.controls cell volume

3. Acidification of endosomes

4. Resting membrane potential in skeletal muscle

Electrochemical driving F favors efflux

Front 20

Na/K -ATPase pumps what in and out?

And this causes what to leak out through a channel?

And also causes a driving force to couple secondary active transport of other ions with bringing what back into the cell?

Back 20

3Na+ out for every 2K+ in

K+ leaks back out thru a channel

Na+ wants to get back in and this electrochemical gradient can be coupled to secondary active transport to bring other ions (e.g. Ca++) OUT

Front 21

"Bad pore"

Back 21

Staphylococcus aureus releases a toxin that inserts into plasma membrane and acts as non-selective pore =lysis and tissue damage

Front 22

Lynch Syndrome (hereditary nonpolyposis colon cancer)

Back 22

Defect of post-replication mismatch repair in patients who are heterozygous for a defect in mismatch repair protein. When there is a somatic mutation, their intact copy becomes dysfunctional and some cells become cancerous. Mismatch repair of mismatched nucleotides happens in stem cells in the G2

phase of the cell cycle.

Front 23

Cockayne Syndrome

Back 23

Defect of transcription-coupled nucleotide excision repair --especially in neurons. Autosomal recessive.

Leads to poor growth, neuro problems, and early senility.

Front 24

Xeroderma pigmentosum

Back 24

Defect in genome-wide nucleotide excision repair. Those that would normally repair pyrimidine dimers (T-T) caused by UV radiation in skin. Leads to lesions and skin cancer .