Genetic variation in selenoprotein S influences inflammatory response.
Chronic inflammation has a pathological role in many common diseases and is influenced by both genetic and environmental factors. Here we assess the role of genetic variation in selenoprotein S (SEPS1, also called SELS or SELENOS), a gene involved in stress response in the endoplasmic reticulum and inflammation control. After resequencing SEPS1, we genotyped 13 SNPs in 522 individuals from 92 families. As inflammation biomarkers, we measured plasma levels of IL-6, IL-1beta and TNF-alpha. Bayesian quantitative trait nucleotide analysis identified associations between SEPS1 polymorphisms and all three proinflammatory cytokines. One promoter variant, -105G --> A, showed strong evidence for an association with each cytokine (multivariate P = 0.0000002). Functional analysis of this polymorphism showed that the A variant significantly impaired SEPS1 expression after exposure to endoplasmic reticulum stress agents (P = 0.00006). Furthermore, suppression of SEPS1 by short interfering RNA in macrophage cells increased the release of IL-6 and TNF-alpha. To investigate further the significance of the observed associations, we genotyped -105G --> A in 419 Mexican American individuals from 23 families for replication. This analysis confirmed a significant association with both TNF-alpha (P = 0.0049) and IL-1beta (P = 0.0101). These results provide a direct mechanistic link between SEPS1 and the production of inflammatory cytokines and suggest that SEPS1 has a role in mediating inflammation.
Curran
Joanne E
JE
Southwest Foundation for Biomedical Research, San Antonio, Texas 78227, USA.
Jowett
Jeremy B M
JB
Elliott
Kate S
KS
Gao
Yuan
Y
Gluschenko
Kristi
K
Wang
Jianmin
J
Abel Azim
Dalia M
DM
Cai
Guowen
G
Mahaney
Michael C
MC
Comuzzie
Anthony G
AG
Dyer
Thomas D
TD
Walder
Ken R
KR
Zimmet
Paul
P
MacCluer
Jean W
JW
Collier
Greg R
GR
Kissebah
Ahmed H
AH
Blangero
John
J
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007249:Inflammation / Q000235:genetics*; D018836:Inflammation Mediators / Q000378:metabolism; D007375:Interleukin-1 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008264:Macrophages / Q000166:cytology / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D034741:RNA, Small Interfering / Q000494:pharmacology; D051140:Selenoproteins; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D018836:Inflammation Mediators; D007375:Interleukin-1; D015850:Interleukin-6; D008565:Membrane Proteins; D034741:RNA, Small Interfering; C487710:SELENOS protein, human; D051140:Selenoproteins; D014409:Tumor Necrosis Factor-alpha