Unit 3: Intro to Transcription Flashcards
MCB 181R University of Arizona
What is transcription?
The process of creating RNA from a DNA template.
What are the three stages of transcription?
Initiation, Elongation, Termination.
What happens during the initiation stage of transcription?
RNA polymerase binds to the DNA at the beginning of a gene.
What happens during the elongation stage of transcription?
RNA polymerase moves along the DNA template, adding RNA nucleotides to create a complementary DNA Strand.
What happens during the termination stage of transcription.
A terminator sequence signals RNA polymerase to detach from the DNA, ending the transcription.
How is the initiation stage of transcription regulated?
By proteins binding to DNA sequences.
What is the role of enhancer sequences in transcription?
They are DNA sequences that can increase transcription when bound by specific proteins (activators).
what are regulatory transcription factors?
Proteins that bind to DNA sequences and can affect the rate of transcription.
What are generally transcription factors?
Proteins that are essential for the binding of RNA polymerase to the promoter and the initiation of transcription.
What happens to the RNA polymerase after termination?
It is now free to transcribe another gene.
What happens to the RNA after transcription in prokaryotes?
The primary transcript of a protein - encoding gene is the mRNA that is translated to make protein molecules.
What happens to the RNA after transcription in eukaryotes?
The primary structure is process in the nucleus to make the mature mRNA. The mature mRNA then leaves the nucleus and enter the cytoplasm, where it is translated to make protein molecules.
What is the role of proteins binding to DNA in transcription?
They affect the transcription initiation.
Where does the growing RNA strand exit from the RNA polymerase?
It exits the RNA polymerase.
What happens to the DNA during elongation?
The DNA is “unzipped” by RNA polymerase.
What to the DNA after RNA polymerase passes?
The DNA is “Zipped up” again.
