Skip to main content
Back

DNA Repair and Recombination definitions

Control buttons has been changed to "navigation" mode.
1/17
  • Depurination
    Loss of purine bases from DNA, creating missing spots in the double helix and potentially leading to mutations if unrepaired.
  • Deamination
    Chemical conversion of a DNA base into a different base, such as cytosine turning into uracil, altering genetic information.
  • Thymine Dimer
    Covalent linkage of adjacent thymine bases, usually caused by UV light, distorting the DNA helix and blocking replication.
  • Double Strand Break
    Severing of both DNA strands, a severe form of damage that can lead to cell death if not properly repaired.
  • Mismatch Repair
    Correction system that detects and fixes base-pairing errors by recognizing distortions in the DNA helix after replication.
  • Base Excision Repair
    Repair pathway that removes chemically damaged bases, often using DNA glycosylase to excise and replace single nucleotides.
  • Nucleotide Excision Repair
    Mechanism that removes bulky DNA lesions, such as thymine dimers, by excising a segment of the strand and filling the gap.
  • Non-Homologous End Joining
    Repair process that directly joins broken DNA ends, often resulting in loss of genetic material at the break site.
  • Homologous Recombination
    Accurate repair of double strand breaks using an undamaged homologous chromosome as a template, preserving genetic information.
  • Endonuclease
    Enzyme that cuts DNA internally, removing damaged sections to create single-stranded regions necessary for repair.
  • RecA Protein
    Stabilizing factor that binds single-stranded DNA during repair, preventing degradation and facilitating strand invasion.
  • Strand Invasion
    Process where a single-stranded DNA segment invades a homologous DNA duplex, pairing with its complementary sequence.
  • Holiday Junction
    Cross-shaped DNA structure formed during homologous recombination, where strands from homologous chromosomes are exchanged.
  • Branch Migration
    Movement of the crossover point in a Holiday Junction, allowing extension of the repaired DNA region during recombination.
  • Crossover
    Exchange of genetic material between homologous chromosomes beyond the damaged area, increasing genetic diversity.
  • Dissolution
    Unwinding of Holiday Junctions without cutting, resulting in repair without exchange of additional genetic material.
  • Resolution
    Cleavage of Holiday Junctions, often leading to crossover and exchange of genetic material between chromosomes.