Topic 2:6c - biotechnology: CRISPR and new proteins

Question 1

What does CRISPR stand for?

Answer 1

Clustered Regularly Interspaced Short Palindromic Repeat

Question 2

What is CRISPR and its purpose?

Answer 2

CRISPR is a genomics editing tool that has the capacity to change parts of gene(s) by removing, adding, or altering sections of DNA. Its purpose is to correct mutations that may otherwise cause disease.

Question 3

CRISPR Cas 9 system contains two main parts:

Answer 3

Cas 9 – a bacterial enzyme that acts as molecular scissors to cut DNA at specific sites.

Guide RNA (gRNA) – ensures that the Cas 9 cuts at the right spots on the DNA.

Question 4

Explain what gRNA is

Answer 4

guide RNA has a short “guide” sequence that binds through complementary base pairing to a specific target sequence of DNA in a genome.

gRNA binds to the cas 9 enzyme, and targets the location at which the cuts the sugar phosphate backbone

Question 5

Explain what the cas 9 enzyme is

Answer 5

the Cas9 enzyme is bonded to the guide RNA and cuts the DNA sugar-phosphate backbone at the targeted location(s).

Question 6

where does gRNA come from?

Answer 6

it is synthesised in the lab, to have a complementary base sequence to the target gene

Question 7

What are the functions of CRISPR, what can it do?

Answer 7

edit genes in a genome:
-Change (edit) specific nucleotides (eg Thymine to Adenine)

-Add (transfer) vital missing genes or other fragments of DNA

-Remove or silence (edit) detrimental DNA

Question 8

What are three applications of CRISPR

Answer 8

• gene therapy: Gene mutations can be corrected using CRISPR/Cas allowing scientists to remove mutations in oncogenes and tumour suppressing genes that are implicated in cancer.

-Agriculture: CRISPR/Cas has been used to insert disease resistant genes into plants

Research: Scientists study the role of gene mutations in the onset and development of diseases by using CRISPR/Cas to create targeted mutations in certain genes

Question 9

what are the steps of manufacturing a new protein for a desired function?

Answer 9

1. identify the unique shape required for the function of the protein
2. identify what amino-acid sequence will result in that shape
3. identify the DNA base sequence that will code for that amino acid sequence
4. Through PCR, synthesise DNA with the base sequence required
5. incorporate this target DNA into cells, through a vector probably plasmids
6. clone the bacteria, isolate and harvest the desired protein molecules that are synthesised as a result of the synthesised DNA

Question 10

What are three applications of the manufacturing of new proteins

Answer 10

• Development of new materials: Scientists design proteins with desirable physical and chemical properties e.g. high tensile strength, improved durability and high ductility
• Targeted chemotherapy: Scientists design proteins that prevent tumour growth by interfering with specific target molecules needed for the replication of cancer cells. Other proteins are designed to attach to the membrane of cancer cells where they attract immune cells that destroy the tumour.
• enzyme design: Scientists design enzymes that bind with a substrate with high specificity. These enzymes are used in the food industry and biomedical research