Transcription

• What is the process called when DNA turns into mRNA?

  Transcription
• Where does RNA transcription occur in a eukaryote?

  In the Nucleus
• Where does RNA transcription occur in prokaryotes?

  In the cytoplasm
• True or false: In PROKARYOTES, Transcription and Translation occur in the cytoplasm at the same time


  TRUE
• Define a gene

  The part of the DNA that is transcribed into RNA
• What is another term for a "gene"


  Transcription unit
• What are the 3 components of a gene?

  • Start Transcription: (+1) In the upstream
  • Upstream
  • Downstream
• In upstream, do the numbers become positive or negative?


  Negative
• In downstream, do the numbers become positive or negative?


  Positive
• What is the region in the upstream also known as?

  The promoter
• What is the promoter composed of?

  A's & T's
• What binds to the promoter? 


  RNAP b/c that is where it starts transcribing
• In EUKARYOTES; what is the A&T rich region called?


  The TATA Box
• How many RNAPs do eukaryotes have?

  3
• In EUKARYOTES; What does RNAP i do?


  Makes rRNA
• In EUKARYOTES; What does RNAP ii do? 


  Makes mRNA (Involved in transcription)
• In EUKARYOTES; What does RNAP iii do? 


  Makes tRNA
• In PROKARYOTES; What is the A&T rich region known as?


  Pribnow Box
• What is the first step of transcription?


  Initiation
• What are the 3 steps of initiation of a prokaryote?

  • RNAP recognises and binds to the promoter
  • DNA unwinds
  • Transcription begins at the start point
• What is the sequence located in the downstream called?

  Terminal Sequence
• What is the PIC

  Transcription Pre Initiation complex
• What are the 2 components that are binding in PIC (In Order)

  • Transcription Factor
  • Inactive (dephosphorylated) RNAP II on promoter
• What does the transcription factor do?


  Protein that helps initiate and regulate transcription
• How do we need to activate RNAP ii?

  Need to phosphorylate RNAp ii on the C-Terminal Domain (CTD)
• True or False: Transcription will begin when CTD on the RNAp ii is phosphorylated


  True
• What is another word for the coding strand 


  sense strand

  • B/C it makes sense
• What is another word for the non coding strand

  • Antisense Strand
  • Template
• What is the transcript?


  Newly synthesized DNA
• What is the second step of transcription?

  Elongation
• What does RNAP do in elongation

  Unwinds DNA
• How many bases does RNAP expose when unwinding DNA

  10 - 20 bases
• What happens ones the RNA nucleotides bind and add complementary pairs to the template?


  RNA detaches from the template and RNAP continues to elongate
• Does the DNA helix reform behind RNAP?

  Yes
• What is the first step of termination in a EUKARYOTE? 


  dephosphorylation of CTD on RNAP ii
• Why does the CTD on RNAP ii need to be deactivated (Dephosphorylation) 


  Reduces the rate of elongation

  Increases rate of pausing
• What is the terminator sequence in a eukaryote?


  AUAAA
• What does the terminator sequence do?


  Stalls and pauses RNAP ii

  BUT... RNAP ii can still continue for a few thousand bases
• How is the terminator sequence started in PROKARYOTES?


  2 G&C rich sequences are inverted on the DNA
• In PROKARYOTES: 'When RNA transcribes the inverted G&C rich sequence what happens?

  They form complementary base pairs with each other