Origin and evolution of the adaptive immune system: genetic events and selective pressures.
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ABSTRACT:
SUBMITTER: Flajnik MF
PROVIDER: S-EPMC3805090 | biostudies-literature | 2010 Jan
REPOSITORIES: biostudies-literature
Publications
Origin and evolution of the adaptive immune system: genetic events and selective pressures.
Flajnik Martin F MF Kasahara Masanori M
Nature reviews. Genetics 20091208 1
The adaptive immune system (AIS) in mammals, which is centred on lymphocytes bearing antigen receptors that are generated by somatic recombination, arose approximately 500 million years ago in jawed fish. This intricate defence system consists of many molecules, mechanisms and tissues that are not present in jawless vertebrates. Two macroevolutionary events are believed to have contributed to the genesis of the AIS: the emergence of the recombination-activating gene (RAG) transposon, and two rou ...[more]
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