The 5-HT3B subunit is a major determinant of serotonin-receptor function

  title={The 5-HT3B subunit is a major determinant of serotonin-receptor function},
  author={Paul A. Davies and Marco Pistis and Michael C. Hanna and John A. Peters and Jeremy J. Lambert and Tim G. Hales and Ewen Kirkness},
The neurotransmitter serotonin (5-hydroxytryptamine or 5-HT) mediates rapid excitatory responses through ligand-gated channels (5-HT3 receptors). Recombinant expression of the only identified receptor subunit (5-HT3A) yields functional 5-HT3 receptors. However, the conductance of these homomeric receptors (sub-picosiemens) is too small to be resolved directly, and contrasts with a robust channel conductance displayed by neuronal 5-HT3 receptors (9–17 pS). Neuronal 5-HT3 receptors also display a… 
Co-expression of the 5-HT3B serotonin receptor subunit alters the biophysics of the 5-HT3 receptor.
Subunit-Dependent Modulation of the 5-Hydroxytryptamine Type 3 Receptor Open-Close Equilibrium by n-Alcohols
The presence of the 5- HT33B subunit in 5-HT3AB receptors significantly reduces the enhancement of gating efficacy by small alcohols without altering the inhibitory actions of large alcohols.
A cytoplasmic region determines single-channel conductance in 5-HT3 receptors
These findings solve the conundrum of the anomalously low conductance of homomeric 5-HT3A receptors and indicate an important function for the HA-stretch in Cys-loop transmitter-gated ion channels.
Differential Composition of 5-Hydroxytryptamine3Receptors Synthesized in the Rat CNS and Peripheral Nervous System
The in situ hybridization histochemistry and reverse transcriptase-PCR amplification was used to demonstrate that 5-HT3Asubunit transcripts are expressed in central and peripheral neurons, and it was determined that neurons of NG projecting to the nucleus tractus solitarium and those of dorsal root ganglia projecting to superficial layers of the spinal cord express 5- HT3A/3B subunits.
The 5-HT3 receptor – the relationship between structure and function
Characterization of the Novel Human Serotonin Receptor Subunits 5-HT3C,5-HT3D, and 5-HT3E
Data show for the first time that the novel 5- HT3 subunits are able to form heteromeric 5-HT3 receptors, which exhibit quantitatively different functional properties compared with homomeric 4-HT2A and 3-HT1 receptors.
Molecular biology of 5-HT receptors
5-HT3 receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database
The 5-HT3 receptor is a ligand-gated ion channel of the Cys-loop family that includes the zinc-activated channels, nicotinic acetylcholine, GABAA and strychnine-sensitive glycine receptors and differs in their allosteric regulation by some general anaesthetic agents, small alcohols and indoles.


5-HT3 receptors are membrane ion channels
The first recordings of currents through single ion channels activated by 5-HT3 receptors are reported, in excised membrane patches from neurons of the guinea pig submucous plexus, implying a role for 5- HT, and perhaps other amines, as a 'fast' synaptic transmitter.
Cloning and functional expression of a human 5-hydroxytryptamine type 3AS receptor subunit.
A quantitative comparison of the pharmacological profiles of human and mouse recombinant 5-HT3R-AS receptor complexes revealed differences in the potencies of some antagonist or agonist compounds tested, the most dramatic example being (+)-tubocurarine, which demonstrated an approximately 1800-fold discrepancy in antagonist potency.
Primary structure and functional expression of the 5HT3 receptor, a serotonin-gated ion channel.
A complementary DNA clone containing the coding sequence of one of these rapidly responding channels, a 5HT3 subtype of the serotonin receptor, has been isolated by screening a neuroblastoma expression library for functional expression of serotonin-gated currents in Xenopus oocytes.
High Calcium Permeability of Serotonin 5‐HT3 Receptors on Presynaptic Nerve Terminals from Rat Striatum
It is concluded that in contrast to the perikaryal 5‐ HT3 receptors, presynaptic 5‐HT3 receptors appear to be uniquely calcium‐permeant.
Ca2+ permeability of cloned and native 5-hydroxytryptamine type 3 receptors.
We have used single-cell imaging of fura-2-loaded cells to examine the Ca2+ signals evoked by activation of 5-hydroxytryptamine type 3 (5-HT3) receptors in undifferentiated N1E-115 neuroblastoma
Molecular cloning of human 5-hydroxytryptamine3 receptor: heterogeneity in distribution and function among species.
The data revealed that the 5-HT3R molecule has interspecies differences in both tissue distribution and functional profile, and the potency of the agonists to induce inward current paralleled that to compete with the radioligand binding, and 2-methyl-5-hydroxytryptamine, a partial agonists for mouse 5- HT3R, was a full agonist for human 5-ht3R.
Functional properties of a cloned 5‐hydroxytryptamine ionotropic receptor subunit: comparison with native mouse receptors.
It is concluded that the receptor expressed from the cloned cDNA is indistinguishable from the 5‐HT3 receptor of N1E‐115 cells, suggesting an identical structure for these two receptors.