The asthma candidate gene NPSR1 mediates isoform specific downstream signalling
Christina Orsmark Pietras1, Johanna Vendelin, Francesca Anedda
1Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden.
BMC Pulmonary Medicine
|June 29, 2011
Summary
Neuropeptide S Receptor 1 (NPSR1) has two variants, NPSR1-A and NPSR1-B, implicated in asthma and allergy. NPSR1-A shows stronger signaling than NPSR1-B, with both regulating similar genes, suggesting isoform-specific roles in disease.
Area of Science:
- Immunology
- Genetics
- Pharmacology
Background:
- Neuropeptide S Receptor 1 (NPSR1) is a validated asthma and allergy susceptibility gene.
- Human NPSR1 encodes two variants, NPSR1-A and NPSR1-B, with distinct C-termini and expression patterns in asthmatic airways.
- Functional differences between NPSR1-A and NPSR1-B remain largely unexamined.
Purpose of the Study:
- To investigate the downstream signaling properties of NPSR1-B.
- To elucidate functional differences between NPSR1-A and NPSR1-B.
Main Methods:
- HEK-293 cells overexpressing NPSR1-A or NPSR1-B were stimulated with neuropeptide S (NPS).
- Genome-scale expression arrays, qRT-PCR, cAMP and Ca²⁺ assays, and pathway-specific reporter assays were employed.
- Concentration-response and time-series analyses were performed.
Main Results:
- Both NPSR1-A and NPSR1-B signal through conserved pathways and regulate similar gene sets.
- NPSR1-A induced stronger signaling on effector genes compared to NPSR1-B.
- CD69, a regulatory T cell marker, was notably upregulated by NPSR1-B.
Conclusions:
- NPSR1-B regulates a gene set largely identical to NPSR1-A.
- NPSR1-A exhibits stronger signaling induction than NPSR1-B.
- Isoform-specific signaling of NPSR1 variants may contribute to pathogenetic processes in asthma and allergy.
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