Characterization of the effects of four HTR3B polymorphisms on human 5-HT3AB receptor expression and signalling

Karen Margrethe Krzywkowski; Paul A. Davies; Andrew J. Irving; Hans Bräuner-Osborne; Anders Asbjørn Jensen

doi:10.1097/FPC.0b013e328310f950

Characterization of the effects of four HTR3B polymorphisms on human 5-HT_3AB receptor expression and signalling

Karen Margrethe Krzywkowski, Paul A. Davies, Andrew J. Irving, Hans Bräuner-Osborne, Anders Asbjørn Jensen

7 Citations (Scopus)

Abstract

BACKGROUND: 5-Hydroxytryptamine 3 (5-HT3) receptors mediate the fast excitatory neurotransmission of serotonin. In this study, we have characterized the effects of four naturally occurring, nonsynonymous variants of the human 5-HT3B subunit on expression and signalling properties of heteromeric 5-HT3AB receptors. METHODS AND RESULTS: 5-HT3AB receptor signalling was studied in a fluorescence-based cell membrane potential assay and by electrophysiology. Expression levels of cotransfected epitope-tagged 5-HT3A and 5-HT3B subunits were determined using enzyme-linked immunosorbent assay and immunocytochemistry. In cells coexpressing 5-HT3A and 5-HT3B(I143T) subunits, cell surface expression levels of 5-HT3B in particular, and also 5-HT3A were markedly reduced compared with those of wild-type (WT) 5-HT3AB receptor-expressing cells. Electrophysiological recordings on cells coexpressing 5-HT3A and 5-HT3B(I143T) indicated cell surface expression of 5-HT3AB(I143T) receptors with macroscopic current kinetics similar to those of WT 5-HT3AB receptors but with 3-fold lower current densities. In the membrane potential assay, 5-HT3AB(I143T)-transfected cells exhibited signalling properties intermediate to those of WT 5-HT3AB and 5-HT3A receptors. Cotransfection of 5-HT3A, 5-HT3AB(I143T) and WT 5-HT3AB subunit cDNAs did not increase cell surface expression of the variant subunit nor did it restore WT 5-HT3AB receptor signalling completely in the membrane potential assay. In contrast to 5-HT3B(I143T), the 5-HT3B variants S156R, V183I and A223T did not give rise to significant changes in 5-HT3AB receptor expression or signalling properties. CONCLUSION: 5-HT3B(I143T)-containing 5-HT3AB receptors display significantly reduced cell surface expression and different signalling properties compared with WT 5-HT3AB receptors. In contrast, three other 5-HT3B variants, S156R, V183I and A223T, do not appear to alter 5-HT3AB receptor expression or signalling.

Original language	English
Journal	Pharmacogenetics and Genomics (Print Edition)
Volume	18
Issue number	12
Pages (from-to)	1027-1040
ISSN	1744-6872
DOIs	https://doi.org/10.1097/FPC.0b013e328310f950
Publication status	Published - 2008

Keywords

Former Faculty of Pharmaceutical Sciences

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10.1097/FPC.0b013e328310f950

Cite this

@article{be768310b54d11ddb04f000ea68e967b,

title = "Characterization of the effects of four HTR3B polymorphisms on human 5-HT3AB receptor expression and signalling",

abstract = "BACKGROUND: 5-Hydroxytryptamine 3 (5-HT3) receptors mediate the fast excitatory neurotransmission of serotonin. In this study, we have characterized the effects of four naturally occurring, nonsynonymous variants of the human 5-HT3B subunit on expression and signalling properties of heteromeric 5-HT3AB receptors. METHODS AND RESULTS: 5-HT3AB receptor signalling was studied in a fluorescence-based cell membrane potential assay and by electrophysiology. Expression levels of cotransfected epitope-tagged 5-HT3A and 5-HT3B subunits were determined using enzyme-linked immunosorbent assay and immunocytochemistry. In cells coexpressing 5-HT3A and 5-HT3B(I143T) subunits, cell surface expression levels of 5-HT3B in particular, and also 5-HT3A were markedly reduced compared with those of wild-type (WT) 5-HT3AB receptor-expressing cells. Electrophysiological recordings on cells coexpressing 5-HT3A and 5-HT3B(I143T) indicated cell surface expression of 5-HT3AB(I143T) receptors with macroscopic current kinetics similar to those of WT 5-HT3AB receptors but with 3-fold lower current densities. In the membrane potential assay, 5-HT3AB(I143T)-transfected cells exhibited signalling properties intermediate to those of WT 5-HT3AB and 5-HT3A receptors. Cotransfection of 5-HT3A, 5-HT3AB(I143T) and WT 5-HT3AB subunit cDNAs did not increase cell surface expression of the variant subunit nor did it restore WT 5-HT3AB receptor signalling completely in the membrane potential assay. In contrast to 5-HT3B(I143T), the 5-HT3B variants S156R, V183I and A223T did not give rise to significant changes in 5-HT3AB receptor expression or signalling properties. CONCLUSION: 5-HT3B(I143T)-containing 5-HT3AB receptors display significantly reduced cell surface expression and different signalling properties compared with WT 5-HT3AB receptors. In contrast, three other 5-HT3B variants, S156R, V183I and A223T, do not appear to alter 5-HT3AB receptor expression or signalling.",

keywords = "Former Faculty of Pharmaceutical Sciences",

author = "Krzywkowski, {Karen Margrethe} and Davies, {Paul A.} and Irving, {Andrew J.} and Hans Br{\"a}uner-Osborne and Jensen, {Anders Asbj{\o}rn}",

note = "Keywords: 5-HT3A; 5-HT3AB; 5-HT3B; expression; function; ligand-gated ion channel; polymorphism; serotonin; single-nucleotide polymorphism; variant",

year = "2008",

doi = "10.1097/FPC.0b013e328310f950",

language = "English",

volume = "18",

pages = "1027--1040",

journal = "Pharmacogenetics",

issn = "1744-6872",

publisher = "Lippincott Williams & Wilkins",

number = "12",

}

TY - JOUR

T1 - Characterization of the effects of four HTR3B polymorphisms on human 5-HT3AB receptor expression and signalling

AU - Krzywkowski, Karen Margrethe

AU - Davies, Paul A.

AU - Irving, Andrew J.

AU - Bräuner-Osborne, Hans

AU - Jensen, Anders Asbjørn

N1 - Keywords: 5-HT3A; 5-HT3AB; 5-HT3B; expression; function; ligand-gated ion channel; polymorphism; serotonin; single-nucleotide polymorphism; variant

PY - 2008

Y1 - 2008

N2 - BACKGROUND: 5-Hydroxytryptamine 3 (5-HT3) receptors mediate the fast excitatory neurotransmission of serotonin. In this study, we have characterized the effects of four naturally occurring, nonsynonymous variants of the human 5-HT3B subunit on expression and signalling properties of heteromeric 5-HT3AB receptors. METHODS AND RESULTS: 5-HT3AB receptor signalling was studied in a fluorescence-based cell membrane potential assay and by electrophysiology. Expression levels of cotransfected epitope-tagged 5-HT3A and 5-HT3B subunits were determined using enzyme-linked immunosorbent assay and immunocytochemistry. In cells coexpressing 5-HT3A and 5-HT3B(I143T) subunits, cell surface expression levels of 5-HT3B in particular, and also 5-HT3A were markedly reduced compared with those of wild-type (WT) 5-HT3AB receptor-expressing cells. Electrophysiological recordings on cells coexpressing 5-HT3A and 5-HT3B(I143T) indicated cell surface expression of 5-HT3AB(I143T) receptors with macroscopic current kinetics similar to those of WT 5-HT3AB receptors but with 3-fold lower current densities. In the membrane potential assay, 5-HT3AB(I143T)-transfected cells exhibited signalling properties intermediate to those of WT 5-HT3AB and 5-HT3A receptors. Cotransfection of 5-HT3A, 5-HT3AB(I143T) and WT 5-HT3AB subunit cDNAs did not increase cell surface expression of the variant subunit nor did it restore WT 5-HT3AB receptor signalling completely in the membrane potential assay. In contrast to 5-HT3B(I143T), the 5-HT3B variants S156R, V183I and A223T did not give rise to significant changes in 5-HT3AB receptor expression or signalling properties. CONCLUSION: 5-HT3B(I143T)-containing 5-HT3AB receptors display significantly reduced cell surface expression and different signalling properties compared with WT 5-HT3AB receptors. In contrast, three other 5-HT3B variants, S156R, V183I and A223T, do not appear to alter 5-HT3AB receptor expression or signalling.

AB - BACKGROUND: 5-Hydroxytryptamine 3 (5-HT3) receptors mediate the fast excitatory neurotransmission of serotonin. In this study, we have characterized the effects of four naturally occurring, nonsynonymous variants of the human 5-HT3B subunit on expression and signalling properties of heteromeric 5-HT3AB receptors. METHODS AND RESULTS: 5-HT3AB receptor signalling was studied in a fluorescence-based cell membrane potential assay and by electrophysiology. Expression levels of cotransfected epitope-tagged 5-HT3A and 5-HT3B subunits were determined using enzyme-linked immunosorbent assay and immunocytochemistry. In cells coexpressing 5-HT3A and 5-HT3B(I143T) subunits, cell surface expression levels of 5-HT3B in particular, and also 5-HT3A were markedly reduced compared with those of wild-type (WT) 5-HT3AB receptor-expressing cells. Electrophysiological recordings on cells coexpressing 5-HT3A and 5-HT3B(I143T) indicated cell surface expression of 5-HT3AB(I143T) receptors with macroscopic current kinetics similar to those of WT 5-HT3AB receptors but with 3-fold lower current densities. In the membrane potential assay, 5-HT3AB(I143T)-transfected cells exhibited signalling properties intermediate to those of WT 5-HT3AB and 5-HT3A receptors. Cotransfection of 5-HT3A, 5-HT3AB(I143T) and WT 5-HT3AB subunit cDNAs did not increase cell surface expression of the variant subunit nor did it restore WT 5-HT3AB receptor signalling completely in the membrane potential assay. In contrast to 5-HT3B(I143T), the 5-HT3B variants S156R, V183I and A223T did not give rise to significant changes in 5-HT3AB receptor expression or signalling properties. CONCLUSION: 5-HT3B(I143T)-containing 5-HT3AB receptors display significantly reduced cell surface expression and different signalling properties compared with WT 5-HT3AB receptors. In contrast, three other 5-HT3B variants, S156R, V183I and A223T, do not appear to alter 5-HT3AB receptor expression or signalling.

KW - Former Faculty of Pharmaceutical Sciences

U2 - 10.1097/FPC.0b013e328310f950

DO - 10.1097/FPC.0b013e328310f950

M3 - Journal article

C2 - 19008750

SN - 1744-6872

VL - 18

SP - 1027

EP - 1040

JO - Pharmacogenetics

JF - Pharmacogenetics

IS - 12

ER -