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The counterbalance theory for evolution and function of paired receptors.

ABSTRACT: Paired receptors are families of membrane proteins containing similar extracellular regions but differing in their potential for signaling with one type able to give inhibitory signals and the other activating. Inhibitory receptors could be good targets for pathogens to restrict immune responses against them. Here we suggest that activating members may have evolved to counterbalance pathogens utilizing the inhibitory pathway. Thus, if a pathogen utilizes any part of the inhibitory receptor to downregulate responses against itself, it may, because of similarities in structure, also bind the activating receptor and give an opposing signal. We evaluate recent structural data on SIRPalpha (signal regulatory protein) and LILRB1 (leukocyte immunoglobulin-like receptor subfamily B member 1) showing evidence of pathogen pressure in nonligand-binding regions of these receptors together with data on pathogen binding to PIRs (paired Ig-like receptors) to provide support for this theory.

SUBMITTER: Barclay AN

PROVIDER: S-EPMC3128988 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature

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The counterbalance theory for evolution and function of paired receptors.

Barclay A Neil AN Hatherley Deborah D

Immunity 20081101 5

Paired receptors are families of membrane proteins containing similar extracellular regions but differing in their potential for signaling with one type able to give inhibitory signals and the other activating. Inhibitory receptors could be good targets for pathogens to restrict immune responses against them. Here we suggest that activating members may have evolved to counterbalance pathogens utilizing the inhibitory pathway. Thus, if a pathogen utilizes any part of the inhibitory receptor to do ...[more]

PMID: 19006692

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The counterbalance theory for evolution and function of paired receptors.

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The counterbalance theory for evolution and function of paired receptors.

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