transcription

Question 1

what are the 5 steps of transcription

Answer 1

RNA polymerase binding(detection of promoters on DNA, requires transcription factors)
DNA chain separation(unwind chain, access nucleotides)
transcription initiation(selection of first nucleotide)
elongation(addition of further nucleotides)
termination(release of finished RNA)

Question 2

what is the role of RNA polymerase bind promoters

Answer 2

to promote the initiation site of transcription

Question 3

what is TBP and what is its role in transcription

Answer 3

TBP(TATA box binding protein), part of a general transcription factor(TFIIF) that determines start and direction of transcription

Question 4

describe the initiation of transcription

Answer 4

it requires additional general transcription factors, TFIIF and RNA polymerase(Pol II) extend the transcript on their own

Question 5

describe the process of elongation in transcription

Answer 5

transcription bubble moves along DNA in one direction, DNA is unwound in front of RNA polymerase and rewound behind, RNA chain made in 5’ to 3’ direction, new RNA strand complimentary to template strand(contains uracil)

Question 6

describe transcription termination

Answer 6

newly synthesised RNA makes stem loop structure, a specific enzyme cleaves the RNA which is then released

Question 7

describe the specific regulation of transcription

Answer 7

requires specific transcription factors, which are DA-binding proteins and bind to specific DNA sequences in vicinity of promoter(enhancers)
can be regulated negatively or positively