Diseases/Clinical Correlations

Question 1

Cyclophosphamide

Answer 1

bi-functional alkylating agent that forms inter and intra strand DNA crosslinks

blocks replication and triggers apoptosis

it is converted to phosphoramide mustard by the liver

Question 2

Rubinstein-Taybi Syndrome

Answer 2

arises by a mutation in CREB binding protein; memory and cognition problems

Question 3

Ricin is what and does what?

Answer 3

a glycosidase that removes adenine bases from various positions of rRNA in the large subunit.

Question 4

What is a glycosidase that removes adenine bases from various positions of rRNA in the large subunit?

Answer 4

ricin

Question 5

What arises by a mutation in CREB binding protein; memory and cognition problems?

Answer 5

Rubinstein-Taybi Syndrome

Question 6

What inactivates EF-2 by ADP-ribosylation?

Answer 6

Diptheria toxin

Question 7

How does diphetia toxin work?

Answer 7

inactivates EF-2 by ADP-ribosylation

Question 8

What happens in I-cell disease?

Answer 8

phosphomannose is not produced so lysosomal proteins do not reach their compartments and function is compromised

undegraded proteins in lysosome

Question 9

What lysosomal storage disease results from phosphomannose not being produced, so lysosomal proteins do not reach their compartments?

Answer 9

I-cell disease

Question 10

What is Charcot Marie Tooth Disease?

Answer 10

mutations in Heat shock proteins (chaperone); lead to protein misfolding disorders

Question 11

Congenital Disorders of glycosylation result in what?

Answer 11

impair N-linked glycosylation of proteins; this will prevent secretion and impair EC enzymatic repair actions;

hypoglycemia, hypotonia

Question 12

Multiple Sulfatase deficiency?

Answer 12

This is a failure in modification of a protein: the thiol group in cysteine can be converted into an aldehyde to form forymlgylcine; this is important for lysosomal sulfatases; a failure to do this cases sulfated glycosaminogylans to accumulate in the lysosome

Question 13

What is a rare mitochondrial disorder, that is caused by a mutation in the TIM component that impair cellular energy production by preventing the assembly of fully functional mitochondira?

Answer 13

Deafness-dystonia syndrome

Question 14

Protein sorting defects can lead to many inherited disorders. What are two we talked about in class?

Answer 14

CTFR: mutation interferes with folding/glycosylation of the protein causing CFTR protein to be moved into the cytosol and degraded.

I-Cell: transfer of phosphate to mannose is impaired; therefore, lysosomal proteins do not reach their compartment

Question 15

Ataxia telangiectasia?

Answer 15

Results from a mutation in the protein kinase ATM; cells are unable to respond to double stranded breaks

Question 16

What disease results from a mutation in ATM causing the cells to be unable to respond to double-stranded breaks?

Answer 16

Ataxia telangiectasia

Question 17

Burkitt’s Lymphoma?

Answer 17

results from a translocation of the c-myc gene; the myc gene is now near the genes encoding antibody heavy chains; results in a continually expressed myc, causing the B-cell to become cancerous?

Question 18

In what cancer do B-cells become cancerous? Why?

Answer 18

Burkitt’s Lymphoma. c-myc is translocated next to the promotor and continually on

Question 19

Retinoblastoma?

Answer 19

defect in RB1 gene;

in hereditary: child inherits 1 RB1 mutated gene; a second mutation can arise and tumors form

sporadic: individuals inhert 2 normal RB1 alleles; however, 2 seperate mutations can arise and cause double blindness

Question 20

What causes Li Fraumeni syndrome?

Answer 20

mutant P53 allelle; appearance of multiple tumors (breast cancer, sarcomas, brain tumors, etc)

dominant negative effect

Question 21

Doxorubicin

Answer 21

human Top II inhibitor and anticancer agent

Question 22

Nalidixic acid and ciprofloxacin?

Answer 22

bacterial top II inhibitor and function as antibiotics

Question 23

Lynch Syndrome?

Answer 23

also called hnpcc.. hereditary nonpoly colorectal carcinoma; caused by a defect in strand-directed mismatch repair; 80% chance of getting colon cancer

Question 24

Xeroderma pigmentosum?

Answer 24

caused by a mutation in nucleotide exicision repair mechanism; sensitivty to light, etc

Question 25

Cytarabine?

Answer 25

analogue of cytidine that contains arabinose in place of ribose; for treatment of leukemias; converted to cytarabine triphosphate in cells; competes with deoxyribose for binding to DNA polymerases and DNA replication and repair is blocked

Question 26

How does the death cap mushroom work?

Answer 26

it contains a-amanitin; which is an inhibitor of Poll II, and blocks the synthesis of mRNA

Question 27

What is rifampicin?

Answer 27

an antibiotic that is an inhibitor of RNA polymerase found in bacteria; human bac not affected

Question 28

What is B-thalassemia?

Answer 28

there is reduced synthesis of the B-chain of hemoglobin; resulting in profound anemia; results from a mutation in the B-globin gene that alters the nucleotide sequence at the intro/exon boundary

-no consensus sequence, resulting in an alternate splice site. Results in either splicing of an exon or splicing of an intro.

Question 29

What antibiotic binds to the small subunit and inhibits initaiton?

Answer 29

Streptomycin

Question 30

What antibiotic binds to the A site and prevents tRNA binding?

Answer 30

tetracycline

Question 31

What antibiotic binds to ribosomes and causes mistranslation of codons?

Answer 31

neomycin and gentamicin

Question 32

What antibiotic prevents peptidyl bond formation?

Answer 32

chloramphenicol