Genetic conflicts and the origin of self/nonself-discrimination in the vertebrate immune system.
Trends Immunol
; 44(5): 372-383, 2023 05.
Article
in En
| MEDLINE
| ID: mdl-36941153
ABSTRACT
Genetic conflicts shape the genomes of prokaryotic and eukaryotic organisms. Here, we argue that some of the key evolutionary novelties of adaptive immune systems of vertebrates are descendants of prokaryotic toxin-antitoxin (TA) systems. Cytidine deaminases and RAG recombinase have evolved from genotoxic enzymes to programmable editors of host genomes, supporting the astounding discriminatory capability of variable lymphocyte receptors of jawless vertebrates, as well as immunoglobulins and T cell receptors of jawed vertebrates. The evolutionarily recent lymphoid lineage is uniquely sensitive to mutations of the DNA maintenance methylase, which is an orphaned distant relative of prokaryotic restriction-modification systems. We discuss how the emergence of adaptive immunity gave rise to higher order genetic conflicts between genetic parasites and their vertebrate host.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Vertebrates
/
Adaptive Immunity
Type of study:
Prognostic_studies
Limits:
Animals
/
Humans
Language:
En
Journal:
Trends Immunol
Journal subject:
ALERGIA E IMUNOLOGIA
Year:
2023
Type:
Article