Human S31 serotonin receptor clone encodes a 5-hydroxytryptamine1E-like serotonin receptor

Area of Science:

• Molecular biology
• Neuropharmacology
• Biochemistry

Background:

• A novel genomic fragment, S31, was cloned, encoding a protein with potential G protein-coupled receptor characteristics.
• Initial analysis suggested the S31 protein belongs to the serotonin receptor subfamily.

Purpose of the Study:

• To confirm the identity and function of the S31 protein as a serotonin receptor.
• To characterize the pharmacological profile of the S31 receptor.

Main Methods:

• Molecular cloning of the S31 genomic fragment.
• Expression of the S31 open reading frame in murine L cells.
• Assay of adenylyl cyclase activity to determine serotonin-mediated inhibition.
• Pharmacological characterization using various serotonin receptor agonists and antagonists.

Main Results:

• Expression of S31 in L cells conferred serotonin-mediated inhibition of adenylyl cyclase activity.
• The rank order of drug potencies for inhibiting adenylyl cyclase was determined: 5-hydroxytryptamine >> methysergide >> ergotamine >> trifluoromethylphenylpiperazine >= 8-hydroxydipropylaminotetralin > 5-carboxyamidotryptamine.
• This potency profile closely matched that of the 1E subtype of serotonin receptors found in the human brain.

Conclusions:

• The S31 protein functions as a serotonin receptor, specifically exhibiting characteristics of the 1E subtype.
• The study provides a detailed pharmacological profile for this novel serotonin receptor.
• This research contributes to understanding serotonin receptor subtypes and their signaling pathways.