95.6k views
3 votes
After DSB occurs, sections of DNA around the __________ ends of the break are cut waste in a process called resection. A overhanging __________ end of the broken DNA molecule then "invades" a similar/identical DNA molecule that is not broken.

1 Answer

2 votes

Final answer:

After double-strand break occurs, sections of DNA around the blunt ends of the break are cut waste in a process called resection. A overhanging staggered end of the broken DNA molecule then "invades" a similar/identical DNA molecule that is not broken.

Step-by-step explanation:

After double-strand break occurs, sections of DNA around the blunt ends of the break are cut waste in a process called resection. A overhanging staggered end of the broken DNA molecule then "invades" a similar/identical DNA molecule that is not broken.

These overhangs, known as "sticky ends", can come back together by hydrogen bonding with complementary overhangs on a piece of DNA cut with the same restriction enzyme. The process of forming hydrogen bonds between complementary sequences on single strands to form double-stranded DNA is called annealing. Addition of an enzyme called DNA ligase permanently joins the DNA fragments when the sticky ends come together.

In summary, after double-strand break (DSB) occurs, the blunt ends are cut waste and the overhanging staggered ends of the broken DNA molecule "invade" a similar/identical DNA molecule, forming sticky ends, which can be joined together through annealing and the action of DNA ligase.

User RAOF
by
7.0k points