Recombinant Tyramine receptor ser-2 (ser-2)
Description
Signaling Mechanisms
Recombinant SER-2 expressed in HEK293 cells demonstrated dual signaling pathways:
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cAMP Inhibition: Tyramine reduced cAMP by 80% via Gαᵢ/o coupling .
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Calcium Mobilization: SER-2 triggered Ca²⁺ influx (EC₅₀ = 1.2 μM), while SER-2A showed weaker activity .
Antagonist profiling revealed:
| Antagonist | Ki (nM) |
|---|---|
| LSD | 2.1 |
| Yohimbine | 85 |
| Chlorpromazine | 1,200 |
In Vivo Functional Roles
Genetic studies in C. elegans revealed SER-2’s roles in:
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Pharyngeal Pumping: SER-2 antagonizes serotonin (5-HT)-stimulated pumping. ser-2 mutants failed to suppress 5-HT-induced pumping upon tyramine exposure .
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Foraging Behavior: ser-2(pk1357) mutants exhibited defective nose-touch response during reversals, indicating SER-2 regulates sensorimotor integration .
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Feeding Suppression: SER-2 in NSM neurons mediates tyramine/octopamine-dependent inhibition of feeding via 5-HT modulation .
Regulatory Mechanisms
Post-translational arginine methylation by PRMT-5 enhances SER-2 signaling:
Comparative Analysis with Insect Tyramine Receptors
While SER-2 is nematode-specific, insect TAR1 receptors share functional similarities:
| Receptor | Organism | Signaling Pathway | Key Function |
|---|---|---|---|
| SER-2 | C. elegans | Gαᵢ/o, Ca²⁺ | Pharyngeal pumping, foraging |
| TAR1 | Drosophila | Gαᵢ/o | Olfactory behavior |
| TAR2 | Drosophila | Gαq, Ca²⁺ | Malpighian tubule function |
Key Research Findings
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Isoform-Specific Pharmacology: SER-2A’s reduced octopamine sensitivity (vs. SER-2) highlights IL3’s role in ligand discrimination .
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Neural Circuit Integration: SER-2 in NSM neurons mediates cross-talk between tyraminergic and serotonergic pathways to regulate feeding .
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Methylation-Dependent Activation: PRMT-5-mediated methylation increases SER-2’s efficacy in vivo, linking epigenetic regulation to GPCR function .
Product Specs
Note: We will prioritize shipping the format currently in stock. However, if you have specific requirements for the format, please indicate them when placing your order. We will accommodate your needs.
Note: All proteins are shipped with standard blue ice packs by default. If you require dry ice shipping, please inform us in advance. Additional charges will apply.
Generally, the shelf life of the liquid form is 6 months at -20°C/-80°C. The shelf life of the lyophilized form is 12 months at -20°C/-80°C.
Target Background
- Tyramine receptor (SER-2) isoforms play a role in regulating pharyngeal pumping and foraging behavior in the nematode Caenorhabditis elegans. PMID: 15569254
