Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.

a change in DNA sequence caused by a mistake made by DNA polymerase during replication

Verified step by step guidance

1. Identify the type of DNA damage: A mistake made by DNA polymerase during replication typically results in a mismatch, where an incorrect nucleotide is incorporated into the newly synthesized DNA strand.
2. Recognize the DNA repair pathway: The primary repair mechanism for correcting mismatches introduced during DNA replication is the Mismatch Repair (MMR) pathway.
3. Understand the MMR process: Mismatch Repair involves the recognition of the mismatch, excision of the incorrect nucleotide, and resynthesis of the correct sequence using the original DNA strand as a template.
4. Consider the key proteins involved: In prokaryotes, the MMR system involves proteins such as MutS, MutL, and MutH, while in eukaryotes, homologous proteins like MSH and MLH are involved.
5. Conclude the reasoning: The MMR pathway is specifically designed to correct errors that escape the proofreading activity of DNA polymerase, ensuring the fidelity of DNA replication.

Key Concepts

DNA Replication and Errors

During DNA replication, DNA polymerase synthesizes new strands of DNA. However, it can occasionally incorporate incorrect nucleotides, leading to mutations. These errors can be spontaneous and may result in a change in the DNA sequence if not corrected. Understanding the types of errors that occur during replication is crucial for identifying the appropriate repair mechanisms.

Mismatch Repair (MMR)

Mismatch repair is a critical DNA repair pathway that corrects errors made during DNA replication, specifically mismatched base pairs. This process involves recognizing the incorrect nucleotide, excising it, and replacing it with the correct one. MMR is essential for maintaining genomic stability and preventing mutations that could lead to diseases such as cancer.

DNA Repair Pathways

DNA repair pathways are cellular mechanisms that identify and correct damage to the DNA molecule. These pathways include various systems such as base excision repair, nucleotide excision repair, and mismatch repair. Each pathway is specialized for different types of DNA damage, and understanding these pathways is vital for comprehending how cells maintain their genetic integrity.