Molecular Genetics & Biotechnology - Lecture Fifteen

Question 1

Central Dogma

Answer 1

Transcription and translation

Question 2

Transcriptional control

Answer 2

Determines when and in what cell a gene is transcribed to produce mRNA

Question 3

The more copies of our gene that is transcribed

Answer 3

The more that can be translated, and therefore the more proteins that can be produced

Question 4

Each cell contains the same ~21,000 protein coding genes, how many of these genes are expressed in a particular cell type?

Answer 4

11,000 to 17,000

Question 5

Transcription

Answer 5

The process where a DNA sequence is copied (transcribed) into an RNA molecule

Question 6

A gene when transcribed

Answer 6

Is turned on or expressed

Question 7

Why is transcription a key control point?

Answer 7

If a gene gets transcribed, it is used to make a protein (expressed), but if a gene is not transcribed in a cell, it can’t be used to make a protein in that cell

Question 8

Transcription factors

Answer 8

Proteins that bind to a specific DNA sequence and control the rate of transcription (DNA or RNA)

Question 9

Regulatory regions or promotors

Answer 9

Which are generally at the start of the gene and they’re going to function to regulate turning a gene and off and on

Question 10

Transcribed region

Answer 10

Sequences of DNA that are copied into RNA (transcribed)

Question 11

How do transcription factors control transcription?

Answer 11

A pair of activators promote transcription

Repressor inhibits transcription

Question 12

Transcription factors are forming a protein complex that is able to recruit RNA polymerase to the promotor

Answer 12

The transcription factors bind first which gives them affinity (able to interact specifically with the protein) so any RNA polymerase in the cell will end up binding to the transcription factors. Once they’ve landed, they’ll be tight and sit on the region then be in a complex where it can recognise the DNA and convert it into RNA