Diseases and Drugs Flashcards
What disease does AZT treat and what is its mechamism of action?
HIV; inhibits reverse transcriptase
What disease does acyclovir treat and what is its method of action?
Herpes; inhibits reverse transcriptase
What is quinolone?
Broad-spectrum antibiotic; inhibits DNA gyrase and replication of DNA
What is the cause of dyskeratosis congenita?
Telomerase deficiency syndrome; causes premature aging
What is the cause of hereditary non-polyposis colorectal cancer (Lynch Syndrome)?
Mutations in MMR (mismatch repair) genes
What is the cause of Hemoglobin Wayne syndrome?
Deletion of U frameshift/sense mutation that results in polypeptide elongation
What is the cause of Thalassemias?
Mutation in beta-globin promoter or complete deletion of locus control region (LCR) of beta-globin gene cluster, resulting in lower levels of hemoglobin production in RBCs
Describe Hemophilia B-Leyden.
Due to a mutation in promoter of Factor IX gene, important in blood clotting. After puberty, Factor IX production increases because androgen can alternatively bind the promoter.
Describe Fragile X Syndrome.
Most common form of mental retardation in boys; results from CGG repeat expansion in 5’UTR of FMR1 gene, causing region to be highly methylated and preventing initiation of transcription.
How does aspirin inhibit production of inflammatory cytokines?
Inhibits IKB phosphorylation, disallowing NF-kB from unbinding and moving into nucleus.
Why does a congenital loss of APC increase the likelihood of developing colon cancer?
APC, a tumor suppressor, is part of the complex that degrades B-catenin. B-catenin is a TF to induce cell proliferation.
How does Rifampicin work?
It binds RNA polymerase in bacteria and blocks the RNA exit channel.
What is alpha-amanitin and what does it do?
Toxin/peptide of death-cap mushroom; prevents RNA Pol II from translocating by binding the bridge helix.
What do Cockayne syndrome, Xeroderma Pigmentosum and Trichothiodystrophy have in common?
Involve mutations/loss of function in TFIIH, which is involved in transcriptional initiation and nucleotide excision repair. Common symptom is photosensitivity.
How does Vorinostat work?
HDAC inhibitor used to treat T-cell lymphoma.
What is Gleevac (imantinib)?
A tyrosine kinase inhibitor used to treat chronic mylogenous leukemia, a disease in which tyrosine kinase in permanently turned on.
What is the molecular basis of Cystic Fibrosis?
F508 gene deletion resulting in misfolded CF transmembrane conductase regulator (CFTR), required to regulate sweat, mucus, and digestive fluids.
Describe Methotrexate.
Competitive inhibitor of dihydrofolate reductase, an enzyme necessary for nucleotide biosynthesis; used in cancer treatment.
How does penicillin work to block bacterial growth?
Irreversibly binds and inhibits glycopeptide transpeptidase and prevents cell wall formation.
Describe Gout.
Due to accumulation of (low-soluble) purines in tissue. Leads to symptoms of arthritis, pain and welling in the joints (often big toe) due to increase in uric acid.
Describe Lesch-Nyhan Disease.
An X-linked trait. A defect in the enzyme the breaks down purines, leading to accumulation in tissues. Leads to symptoms of gout and self-destructive biting
Describe Cysplatin.
A chemotherapetuic alkylating agent. Causes crosslinks in DNA that are not remedies by repair mechanisms and lead to cell death.
Describe Acyclovir.
A nucleoside analogue that is incorporated during replication and that then blocks DNA polymerase. An antiviral.
Describe Adriamycin.
AKA doxorubicin, a chemotherapy drug; intercalates (inserts) between planar bases of DNA, inhibiting topoisomerase
Describe Puromycin.
A nucleotide analogue that mimics tRNA acceptor region, allowing peptide transfer and premature termination of translation. An antibiotic.
Describe spinal muscular atrophy.
Caused by defect in SNM1 gene that encodes for SMN protein (survival of motor neuron protein), which is an essential component of splicesomal machinery.
Describe Erythromycin.
Antiobiotic; affects peptidyl transferase process of translation
Describe Rapamycin.
mTOR protein-kinase inhibitor; kinase phosphorylates 4E-BP, prohibiting it from sequestering 4E, a binding protein of translation. A common immunosuppressant.
Describe Craniosynostosis.
Causes premature fusion of cranial sutures; Proline to histidine substitution within MSX2 homeodomain causes stronger protein binding, “gain of function” mutation
Describe Androgen-Insensitivity Syndrome.
Due to mutation in DNA binding domain of androgen receptor (a Zn-finger DNA binding protein)
Describe Waardenburg Syndrome Type II.
A pigmentation anomaly due to mutation in MITF gene which encodes a bHLH binding protein, rendering the protein non-functional.
Describe Rubinstein-Taybi Syndrome.
Characterized by short stature, broad fingers and toes. Due to mutation in CBP (a HAT co-activator) for many TFs.
How does Tamoxifen work?
An estrogen antagonist prevents binding of estrogen to estrogen receptor, which then cannot dimerize and bind to DNA to recruit HATs.
Describe Cyclosporin.
An immunosuppressant that inhibits calcineurin, a calcium-dependent kinase that acts on NF-AT, activating it to move into the nucleus to affect transcription of T-cells.
What is the preferred secretase pathway of the APP (amyloid precursor protein)?
Alpha, then gamma. If beta, than gamma, protein is AB40 or AB42.
Describe Prion Disease.
Due to misfolding of the prion protein into aggregates composed of a large proportion of beta-sheets.
