Q. Consider the following statements regarding the CRISPR-Cas9 system:
1.CRISPR acts as a guide RNA molecule that identifies the target DNA sequence through complementary base-pairing.
2.The Cas9 protein acts as a molecular scissor that makes a site-specific cut in the DNA.
Which of the statements given above is/are correct?
Answer: C
Notes:
Explanation:
CRISPR-Cas9 is a precise gene-editing tool where the guide RNA (gRNA) component scans and identifies the target DNA sequence via complementary base-pairing. The Cas9 protein serves as a molecular scissor, creating a site-specific double-strand break in the DNA.
Key Aspects of CRISPR-Cas9 Technology:
- Mechanism: It consists of two components: the guide RNA (gRNA), which finds the specific DNA sequence, and the Cas9 enzyme, which cuts it.
- Targeting: The guide RNA binds to specific DNA bases, enabling precise gene identification.
- Cleavage: The Cas9 nuclease cuts the target DNA, allowing for the deletion, addition, or modification of genes.
- Origin: The system is derived from a natural defense mechanism in bacteria and archaea, which use it to fight viral attacks.
- Applications: It is used in biotechnology for genome editing, including in medicine for gene therapy and in agriculture for crop improvement.
