Learn.
Transcription is taking RNA and turning that into DNA. This is more prone to errors since there is no prof reading as they go (unlike DNA synthesis). DNA has regions known as promoters – this initiates RNA transcription, however, there are more complex regulatory actions at play. Additionally, short sections being repeatedly copied makes it more prone to error.
DNA unwinds its self, the same as it does in DNA replication. However, only one strand of the DNA is replicated. This strand in known as the template strand. The strand which is copied is known as the template DNA strand. Hence the sequence of the RNA matches that of the non-template strand.
RNA Polymerase is slow at inititaition of the RNA molecule, however, Chain-elongation is rapid this involves connecting nucleotides. A transcription factor signals where RNA transcription will commence.
Termination
- G/C rich regions have more hydrogen bonding resulting in the formation of a ds hairpin. This dissasociates the RNA out from the polymerase resulting in RNA termination.
- Alternativly, a RHO protein travels along the DNA and physically forces the RNA out of the polymerase molecule. This results in the dissasociation of the RNA from the polymerase molecule.
Master.
Question 1.
Explain how DNA is transcripted into RNA
Question 2.
Outline problems and their biological solution in transcription.
Question 3.
Describe the proteins function for RNA transcription
Question 4.
Compare and contrast the differences between DNA and RNA
Answers.