Answer to Question #166248 in Molecular Biology for Jasmine Elfaqir

Question

) When so much damage occurs in DNA that during excision reparation the cell does not have time to completely eliminate them. As a result, after replication of this DNA the daughter chain has “gaps” that are formed at the site of damage of the mother DNA chain,.

1. What type of reparation corrects such damage?

2. What are the molecular mechanisms the cause of this disorder?

3. Feature of postreplication reparation.

4. What other types of postreplication reparation do you know, describe.

Answer 1

1. Recombination repair.

2. Molecular mechanism cause of this disorder occurs when damaged nucleotides are cut out of the growing strand such that a lesion is created, the final remaining strand is used as a template for synthesis a complimentary strand often past the lesion leaving a gap at the lesion site.

3.In postreplication repair, the replication polymerase either stops at the replication fork when DNA damage is detected or proceeds past the damaged base, leaving a gap.

4. Other types of postreplication reparation include;

Base excision repair, a mechanism that recognizes and repair damaged DNA that do not have significant distortion go the helical DNA structure.

Mismatch repair, used to repair errors as a result of DNA synthesis by recognizing, excising misincorperated nucleotides and replacing them with the correct ones.