Transcription, RNA processing, and translation machinery tested on USMLE Step 1.
38 cards · basic cards · AI-written, checked twice. Edit anything.
- Which eukaryotic RNA polymerase synthesizes ribosomal RNA (28S, 18S, and 5.8S)?
- RNA polymerase I
- Which eukaryotic RNA polymerase synthesizes mRNA and most snRNA?
- RNA polymerase II
- Which eukaryotic RNA polymerase synthesizes tRNA and 5S ribosomal RNA?
- RNA polymerase III
- Alpha-amanitin inhibits which RNA polymerase?
- RNA polymerase II
- What mushroom is the source of the RNA polymerase II inhibitor alpha-amanitin?
- Amanita phalloides (the death cap mushroom)
- What eukaryotic promoter element, located about 25 base pairs upstream of the transcription start site, helps position RNA polymerase II?
- TATA box
- What upstream eukaryotic promoter element, located roughly 75 base pairs upstream of the start site, helps regulate transcription frequency?
- CAAT box
- What chemical structure is added to the 5' end of eukaryotic pre-mRNA during processing?
- A 7-methylguanosine (m7G) cap
- What enzyme adds the poly-A tail to the 3' end of pre-mRNA?
- Poly-A polymerase
- What consensus sequence signals the site of cleavage and polyadenylation on pre-mRNA?
- AAUAAA
- What structure removes introns from pre-mRNA?
- The spliceosome
- What are the RNA-protein complexes that make up the spliceosome called?
- snRNPs (small nuclear ribonucleoproteins)
- During pre-mRNA splicing, the ____ adenine attacks the 5' splice site to form a lariat intermediate.
- branch point
- What two-nucleotide consensus sequence marks the 5' splice (donor) site of an intron?
- GU
- What two-nucleotide consensus sequence marks the 3' splice (acceptor) site of an intron?
- AG