4- DNA and how genes work reading the code

Question 1

How is gene expression regulated at the level of transcription?

Answer 1

DNA packaged around histone proteins
Histone modification regulates access to the DNA
Histone acetylation increases transcription
Modification of histones a cancer therapy

Question 2

What are transcription factors for?

Answer 2

Create the conditions for transcription

Question 3

What is alternative splicing?

Answer 3

Some RNAs use different combinations of exons to form different proteins
Regulated by cell conditions
This has a profound effect upon protein function

Question 4

What are microRNAs?

Answer 4

small “non-coding” regulatory RNAs

Question 5

How do microRNAs regulate their target mRNAs?

Answer 5

Cause them to be degraded

Prevent them from being translated

Question 6

How does each stage in a PCR contribute to amplification of a specific DNA sequence?

Answer 6

1. Everything denatured at 95C
2. Annealing step at 55C - primer bind to the opposite strand
3. Extension phase 72C the primers are extended towars each other at the 3’-OH group

Question 7

What are the components required for a PCR reaction?

Answer 7

Target DNA
Foward and reverse primers
Deoxynucleotide triphosphates PCR buffer monovalent salts
DNA polymerase

Question 8

What is the significance of NGS?

Answer 8

Allows the sequencing of millions of pieces of DNA at the same time
This enables the collection of large amounts of genetic information about individual patients which can be used to inform them what the best treatment is