Toll-Like Receptor Evolution in Birds: Gene Duplication Pseudogenization, and Diversifying Selection

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F18%3A10379255" target="_blank" >RIV/00216208:11310/18:10379255 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1093/molbev/msy119" target="_blank" >https://doi.org/10.1093/molbev/msy119</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/molbev/msy119" target="_blank" >10.1093/molbev/msy119</a>

Result language

angličtina

Original language name

Toll-Like Receptor Evolution in Birds: Gene Duplication Pseudogenization, and Diversifying Selection

Original language description

Toll-like receptors (TLRs) are key sensor molecules in vertebrates triggering initial phases of immune responses to pathogens. The avian TLR family typically consists of ten receptors, each adapted to distinct ligands. To understand the complex evolutionary history of each avian TLR, we analyzed all members of the TLR family in the whole genome assemblies and target sequence data of 63 bird species covering all major avian clades. Our results indicate that gene duplication events most probably occurred in TLR1 before synapsids diversified from sauropsids. Unlike mammals, ssRNA-recognizing TLR7 has duplicated independently in several avian taxa, while flagellin-sensing TLR5 has pseudogenized multiple times in bird phylogeny. Our analysis revealed stronger positive, diversifying selection acting in TLR5 and the three-domain TLRs (TLR10 [TLR1A], TLR1 [TLR1B], TLR2A, TLR2B, TLR4) that face the extracellular space and bind complex ligands than in single-domain TLR15 and endosomal TLRs (TLR3, TLR7, TLR21). In total, 84 out of 306 positively selected sites were predicted to harbor substitutions dramatically changing the amino acid physicochemical properties. Furthermore, 105 positively selected sites were located in the known functionally relevant TLR regions. We found evidence for convergent evolution acting between birds and mammals at 54 of these sites. Our comparative study provides a comprehensive insight into the evolution of avian TLR genetic variability. Besides describing the history of avian TLR gene gain and gene loss, we also identified candidate positions in the receptors that have been likely shaped by direct molecular host-pathogen coevolutionary interactions and most probably play key functional

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10602 - Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Molecular Biology and Evolution

ISSN

0737-4038

e-ISSN

—

Volume of the periodical

35

Issue of the periodical within the volume

9

Country of publishing house

US - UNITED STATES

Number of pages

15

Pages from-to

2170-2184

UT code for WoS article

000452565900007

EID of the result in the Scopus database

2-s2.0-85055529438