Pathway · 2 proteins
Recombination and restart
Recombination factors and helicases support DNA repair or recovery.
How it works
- RecA is the strand-exchange protein that forms a filament on single-stranded DNA and pairs it with a homologous duplex; RecR is a recombination mediator that helps load it.
- RecG is an ATP-dependent helicase that migrates Holliday junctions, and RuvX is a resolvase that cleaves them so the intermediates can be separated.
- Together these activities support recombinational repair and the restart of stalled forks. Which route a particular lesion takes depends on the intermediate formed, and the annotation does not choose between them.
Grouped by the atlas’s curated pathway map. The table order is not a proven reaction order.
Its proteins
| Protein | EC | Reaction (UniProt) | Metal or cluster | Amino acids | Certainty |
|---|---|---|---|---|---|
| Recombination protein RecR | — | — | — | 211 | Step named |
| ATP-dependent DNA helicase RecG | 5.6.2.4 | Couples ATP hydrolysis with the unwinding of duplex DNA by translocating in the 3'-5' direction. | — | 792 | Step named |
Also part of this pathway
These proteins are described under another pathway, but also take part here.
| Protein | EC | Reaction (UniProt) | Metal or cluster | Amino acids | Certainty |
|---|---|---|---|---|---|
| Protein RecAHome: DNA damage repair | — | — | — | 345 | Step named |
| Putative pre-16S rRNA nucleaseHome: Not yet placed in a pathway | 3.1.-.- | — | — | 131 | Step named |
Origins
What happens when DNA copying stalls, and how was that handled before these proteins existed?
The books searched discuss recombination mainly in present-day cells.
Replication forks stall at damage and breaks. Restart proteins recognise the stalled fork, rebuild it and reload the helicase, so that copying of a whole chromosome can finish.
The wider question for this part of the cell: origins for copying and repairing the genome.
Sources
- Atlas pathway grouping from the VF5 reference-genome system map (Deckert et al. 1998; Braakman & Smith 2014)
Other pathways in this group: DNA damage repair · DNA synthesis · Topology management · Joining and end processing · Chromosome preparation · Initiation and opening · Homologous recombination · Base excision repair · Cysteine and methionine metabolism · Not yet placed in a pathway