Warning: file_get_contents(https://eutils.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&id=28180967
&cmd=llinks): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 215
The evolution of the natural killer complex; a comparison between mammals using
new high-quality genome assemblies and targeted annotation
#MMPMID28180967
Schwartz JC
; Gibson MS
; Heimeier D
; Koren S
; Phillippy AM
; Bickhart DM
; Smith TP
; Medrano JF
; Hammond JA
Immunogenetics
2017[Apr]; 69
(4
): 255-269
PMID28180967
show ga
Natural killer (NK) cells are a diverse population of lymphocytes with a range of
biological roles including essential immune functions. NK cell diversity is in
part created by the differential expression of cell surface receptors which
modulate activation and function, including multiple subfamilies of C-type lectin
receptors encoded within the NK complex (NKC). Little is known about the gene
content of the NKC beyond rodent and primate lineages, other than it appears to
be extremely variable between mammalian groups. We compared the NKC structure
between mammalian species using new high-quality draft genome assemblies for
cattle and goat; re-annotated sheep, pig, and horse genome assemblies; and the
published human, rat, and mouse lemur NKC. The major NKC genes are largely in the
equivalent positions in all eight species, with significant independent
expansions and deletions between species, allowing us to propose a model for NKC
evolution during mammalian radiation. The ruminant species, cattle and goats,
have independently evolved a second KLRC locus flanked by KLRA and KLRJ, and a
novel KLRH-like gene has acquired an activating tail. This novel gene has
duplicated several times within cattle, while other activating receptor genes
have been selectively disrupted. Targeted genome enrichment in cattle identified
varying levels of allelic polymorphism between the NKC genes concentrated in the
predicted extracellular ligand-binding domains. This novel recombination and
allelic polymorphism is consistent with NKC evolution under balancing selection,
suggesting that this diversity influences individual immune responses and may
impact on differential outcomes of pathogen infection and vaccination.
free
free
free
