restriction-modification system

Edge evidence

• restriction-modification system enables DNA restriction-modification system RO:0002327

  R-M systems realize self-vs-non-self discrimination by paired methylation and restriction.

  • DOI:10.1128/MMBR.00044-12 Vasu & Nagaraja review R-M systems and their defense functions.
• DNA restriction-modification system mitigates foreign DNA METPO:2007407

  Restriction endonuclease cleavage destroys unmethylated foreign DNA before it can establish.

  • DOI:10.3389/fmicb.2015.00528 R-M systems as engines of genomic diversity through differential cleavage of foreign DNA.
• cognate DNA methyltransferase methylates host recognition site methylation

  The cognate methyltransferase methylates host recognition sites, marking self DNA.

  • DOI:10.1093/nar/gkad452 A methyltransferase methylates those sites to protect host DNA (shaw2023).
• host recognition site methylation protects against restriction endonuclease cleavage

  Methylation of host recognition sites protects self DNA from cognate restriction endonuclease cleavage.

  • DOI:10.1093/nar/gkad452 Host DNA is protected while incoming foreign DNA lacking the same methylation is cleaved (shaw2023).
• restriction endonuclease has function restriction endonuclease cleavage RO:0000085

  The restriction endonuclease cleaves unmethylated foreign double-stranded DNA.

  • DOI:10.1093/nar/gkad452 A restriction endonuclease cuts double-stranded DNA; unmethylated foreign DNA is cleaved (shaw2023).
• restriction endonuclease cleavage mitigates foreign DNA METPO:2007407

  Restriction endonuclease cleavage destroys unmethylated foreign DNA.

  • DOI:10.1093/nar/gkad452 Incoming foreign DNA lacking host methylation is cleaved (shaw2023).
• type IV restriction enzyme cleaves methylated DNA motif

  Type IV restriction enzymes cleave methylated DNA motifs, complementing Types I-III that cleave unmethylated DNA.

  • DOI:10.3390/microorganisms11122962 Type IV enzymes cut methylated motifs (kottenhahn2023).
• plasmid-encoded methylase protects against restriction endonuclease cleavage

  Plasmid-encoded methylases pre-methylate plasmid DNA, protecting it from host restriction activity.

  • DOI:10.1093/nar/gkae896 Some plasmids encode methylases that protect against restriction activity (dimitriu2024).
• phage-encoded DNA methyltransferase protects against restriction endonuclease cleavage

  Phage-encoded DNA methyltransferases methylate the phage genome to reduce host RM restriction.

  • DOI:10.1128/MMBR.00044-12 Phages encode DNA methyltransferases to protect their genomes from restriction (vasu2013).