Asked by jamar
what stabilize the dna molecule during replication
All Answers 1
Answered by
GPT-5 mini
AI
Several things stabilize the DNA and the replication fork while DNA is being copied:
- Intrinsic base-pairing and base-stacking — hydrogen bonds between complementary bases and aromatic stacking give the double helix its basic stability.
- Helicase — unwinds the double helix to expose single strands for copying.
- Single-strand binding proteins (SSBs in bacteria; RPA in eukaryotes) — coat single-stranded DNA to prevent reannealing and secondary structures.
- Topoisomerases (DNA gyrase in bacteria) — relieve torsional stress and prevent supercoiling ahead of the fork.
- Sliding clamp (beta clamp in bacteria; PCNA in eukaryotes) and clamp loader — hold DNA polymerase on the template, greatly increasing processivity and stability of the replication complex.
- DNA polymerases with proofreading (3'→5' exonuclease) — ensure accurate, stable DNA synthesis.
- Primase, ligase and Okazaki-fragment processing enzymes — provide primers and join fragments on the lagging strand so the newly made strand is continuous and stable.
- Chromatin assembly factors (e.g., CAF-1) and histone chaperones — rapidly reassemble nucleosomes on newly synthesized DNA in eukaryotes.
- Telomerase — maintains chromosome ends in eukaryotic linear chromosomes, stabilizing terminal sequences during replication.
Together these factors keep the replication fork intact, prevent damage or misfolding of single strands, and ensure accurate, continuous synthesis. Would you like more detail on any specific factor?
- Intrinsic base-pairing and base-stacking — hydrogen bonds between complementary bases and aromatic stacking give the double helix its basic stability.
- Helicase — unwinds the double helix to expose single strands for copying.
- Single-strand binding proteins (SSBs in bacteria; RPA in eukaryotes) — coat single-stranded DNA to prevent reannealing and secondary structures.
- Topoisomerases (DNA gyrase in bacteria) — relieve torsional stress and prevent supercoiling ahead of the fork.
- Sliding clamp (beta clamp in bacteria; PCNA in eukaryotes) and clamp loader — hold DNA polymerase on the template, greatly increasing processivity and stability of the replication complex.
- DNA polymerases with proofreading (3'→5' exonuclease) — ensure accurate, stable DNA synthesis.
- Primase, ligase and Okazaki-fragment processing enzymes — provide primers and join fragments on the lagging strand so the newly made strand is continuous and stable.
- Chromatin assembly factors (e.g., CAF-1) and histone chaperones — rapidly reassemble nucleosomes on newly synthesized DNA in eukaryotes.
- Telomerase — maintains chromosome ends in eukaryotic linear chromosomes, stabilizing terminal sequences during replication.
Together these factors keep the replication fork intact, prevent damage or misfolding of single strands, and ensure accurate, continuous synthesis. Would you like more detail on any specific factor?
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.