What accounts for the negative charge of DNA?
What accounts for the positive charge of histones?
Lysine and arginine
Condensed, transcriptionally inactive, sterically inaccessible genetic information
Less condensed, transcriptionally active, sterically accessible genetic information
Carbon sources for purines
Nitrogen sources for purines
Carbon sources for pyrimidines
Nitrogen sources for pyrimidines
What nucleotides are purines?
Arginine and Guanine
What nucleotides are pyrimidines?
Thymine/Uracil and Cytosine
Rate-limiting step in pyrimidine synthesis
Rate-limiting step in purine synthesis
Glutamine PRPP aminotransferase
S/S of orotic aciduria
Orotic acid in urine
Meagloblastic anemia that does not improve with B12 or folate
Failure to thrive
MOA of mycophenylate
Inhibition of IMPDH
How does UV light damage DNA
Creates thymine dimers on the same strand of DNA
Enzyme deficiency in Lesch-Nyhan syndrome
Hypoxanthine guanine phophoribosyl transferase (HGPRT)
MOA of adenosine deaminase (ADA)
Converts adenosine to inosine
Adenosine deaminase deficiency leads to what disease?
Autoimmune disease a/w anti-DNA topoisomerases
Diffuse scleroderma (Anti-Scl-70)
DNA pol. that replicates that lagging strand and synthesizes a RNA primer
DNA pol. that repairs DNA
Beta and Epsilon
DNA pol. that replicates mit. DNA
DNA pol. that replicates the leading strand
What are the components of a primasome?
DNA helicase and Primase
Four mechanisms of DNA repair
Nucleotide excision repair
Base excision repair
Nonhomologous end joining
DNA mismatch repair is defective in what pathology?
Hereditary nonpolyposis colorectal cancer (HNPCC)
Nucleotide excision repair is defective in what pathology?
DNA repair defect a/w hypersensitivity to UV light and an 1000x increased risk of skin cancers
DNA repair defect a/w sensitivity to ionizing radiation, immunodeficiency and ataxia beginning at 1-2 yrs
DNA repair defect a/w hypersensitivity to sunlight, leukemias and lymphomas, and average age of cancer onset is 25 yrs
What is the characteristic sequence of the promoter region?
-25 TATA box
-75 CATT box
mRNA stop codons
UGA, UAA, UAG
Name the 4 DNA binding motifs
MOA of alpha-amanitin
Cap mushroom chemical that inhibits RNA pol. II
RNA pol. that makes rRNA
RNA pol. that makes mRNA
RNA pol. that makes tRNA
What is hnRNA
Initial transcript of RNA before it is processed into mRNA
Post transcription modifications of hnRNA
Splicing out of introns
tRNA are charged with an amino acid at which end?
Enzyme that charges tRNA with an amino acid
Antibiotic(s) that binds the 30s ribosomal subunit and prevents attachment of aminoacyl-tRNA
Antibiotic(s) that inhibits the 50s ribosomal peptidyltransferase
Streptogramins and chloramphenicol
Antibiotic(s) that blocks translocation at the 50s ribosomal subunit
Macrolides and linzolide
Antibiotic(s) that inhibit prokaryotic RNA polymerase
Antibiotic(s) that inhibit prokaryotic topoisomerases
Antibiotic(s) that inhibit prokaryotic DHFR
Three different mechanisms cells employ to break down proteins
Ca++ dependent enzymes
Enzyme that catalyzes peptide bond formation during protein synthesis