Genetic effect of CysLTR2 polymorphisms on its mRNA synthesis and stabilization.
BACKGROUND
We previously demonstrated that single nucleotide polymorphism (SNP) and haplotypes were associated with aspirin hypersensitivity in asthmatics. We investigated the genetic effects of the SNPs and haplotypes on the expression of the CysLTR2 gene.


METHODS
We measured CysLTR2 protein and mRNA expression in EB virus-infected B cell lines from asthmatics having ht1+/+ and ht2+/+. A gel retardation assay was used to identify nuclear protein binding to the c.-819 promoter site. The function of promoter and 3'-UTR were assessed using pGL3 luciferase and pEGFP reporter system, respectively.


RESULTS
We found that the expression of CysLTR2 protein was higher in B cell lines of asthmatics having ht2+/+ than in those having ht1+/+. PMA/ionomycin induced higher mRNA expression of CysLTR2 in B cell lines from ht2+/+ asthmatics than those from ht1+/+ asthmatics. A nuclear protein from the B cell lines showed stronger DNA binding affinity with a probe containing c.-819T than one containing c.-819G. The luciferase activity of the c.-819T type of CysLTR2 promoter was higher than that of the c.-819G type. EGFP expression was higher in the EGFP-c.2078T 3'-UTR fusion construct than in the c.2078C construct.


CONCLUSIONS
The sequence variants of CysLTR2 may affect its transcription and the stability of its mRNA, resulting in altered expression of CysLTR2 protein, which in turn causes some asthmatics to be susceptible to aspirin hypersensitivity.
Genome Research Center for Allergy and Respiratory Diseases, Soonchunhyang University Bucheon Hospital, 1174, Jung Dong, Wonmi Ku, Bucheon, Gyeonggi Do, 420-767, Korea. jamies01@empal.com
Jeong-Ah
JA
Shin
Hun Soo
HS
Chang
Se-Min
SM
Park
An-Soo
AS
Jang
Sung Woo
SW
Park
Jong Sook
JS
Park
Soo-Taek
ST
Uh
Gune
G
Il Lim
Taiyoun
T
Rhim
Mi-Kyeong
MK
Kim
Inseon S
IS
Choi
Il Yup
IY
Chung
Byung Lae
BL
Park
Hyoung Doo
HD
Shin
Choon-Sik
CS
Park
D001241:Aspirin / Q000009:adverse effects; D001249:Asthma / Q000139:chemically induced / Q000235:genetics*; D002460:Cell Line; D004342:Drug Hypersensitivity / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D005434:Flow Cytometry; D015870:Gene Expression; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D008156:Luciferases; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D020871:RNA Stability / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis*; D018077:Receptors, Leukotriene / Q000235:genetics*
D012333:RNA, Messenger; D018077:Receptors, Leukotriene; C412375:cysteinyl leukotriene receptor 2; D008156:Luciferases; D001241:Aspirin