sequence of eventscountermeasure

Earlier anti-CRISPRsIntervene before DNA destruction is completed

1CRISPR surveillance

The bacterial complex searches for matching phage DNA.

2Target binding

AcrF1 or AcrF2 prevents the complex from binding its DNA target.

Blocked here

3Cas3 recruitment

If recognition occurs, AcrF3 can prevent the destructive component from joining.

Or here

4No successful degradation

The attack is obstructed before the genome is destroyed.

HealerReported post-cleavage response

1CRISPR cuts

The phage genome is cleaved; Healer does not stop this first event.

2DNA is exposed

Single-stranded regions can appear around the break.

3Gp63 responds

Gp63 binds single-stranded DNA and promotes Gp64-mediated homologous recombination.

Acts here

4Repair supports survival

Matching DNA sequences help restore damaged genetic material.

Authors’ model

The two tracks compare timing and mechanism; they do not imply that the proteins share a structure or operate in the same molecular system.