Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders

Dissertation (MSc (Human Physiology))--University of Pretoria, 2022.

Saved in:
Bibliographic Details
Other Authors: Newton, Claire
Format: Thesis
Language:English
Published: University of Pretoria 2023
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613644435488768
access_status_str Open Access
author2 Newton, Claire
author_browse Newton, Claire
author_facet Newton, Claire
collection Thesis
dc_rights_str_mv © 2022 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc (Human Physiology))--University of Pretoria, 2022.
format Thesis
id oai:repository.up.ac.za:2263/89707
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:39:25.358Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2023
publishDateRange 2023
publishDateSort 2023
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/89707 Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders Newton, Claire michellesteven007@gmail.com Anderson, Ross Steven, Michelle Anne UCTD G protein-coupled receptors Oxytocin receptor Arginine vasopressin receptor 1a and 1b Psychological disorders Birth disorders Dissertation (MSc (Human Physiology))--University of Pretoria, 2022. Oxytocin (OXT) and arginine vasopressin (AVP) are well known for their classical roles in initiation of myoepithelial contractions during labour and lactation, and regulation of blood pressure and osmolality, respectively. However, there is also substantial evidence supporting central roles of these neuropeptides in neuronal and cognitive functioning. Indeed, their altered signalling has been implicated in several psychological disorders, social impairments, and behavioural traits. OXT and AVP elicit their effects through interaction with cognate G protein-coupled receptors (GPCRs). The OXT receptor (OXTR) and two AVP receptor subtypes (AVPR1a and AVPR1b) are expressed in many brain regions. Several studies have highlighted the potential association of genetic variants of these receptors with behavioural/social disorders. Yet, the impacts of these variants on receptor function are often unknown. Through literature research, a selection of naturally occurring OXTR and AVPR1a/1b variants (11 and 7 variants, respectively) associated with a variety of psychological disorders, were identified. In the case of the OXTR, a range of variants linked to birth disorders (a group of disorders in which OXTR variants/ disrupted OXT function has a very well characterised role) were included for comparison. The variants were first analysed using in silico methods to predict their effects on receptor function. This was followed by in vitro characterisation of receptor expression (by receptor ELISA assay), receptor signalling (by inositol phosphate accumulation assay) and ligand binding (by radiolabelled ligand binding assay). This in vitro analysis demonstrated that OXTR variants V45L, A63V, M133V, H173R, W203R, G221S, A238T, I266V, T273R, T273M and V281M, AVPR1a variant F136L and AVPR1b variants K65N, G191R, R364H and R364L, result in severe or partial reduction in receptor function and, therefore, these variants may contribute to the pathophysiologies of psychological/birth disorders that have been indicated in genetic association studies. The nature of dysfunction for each receptor was then further characterised. For the OXTR the majority are believed to be Class II and IV variants, while Class IV variants seem to predominate for AVPR1a/b. From comparison of the in silico prediction outcomes and in vitro analyses, it was iv apparent that the ability of variant effect prediction (VEP) programs to successfully predict the functional consequences of GPCR variants was variable and, in some cases, unreliable. The VEP program SIFT appeared most reliable for future in silico analysis of OXTR, while LRT, Mutation Assessor and Mutation test, have the highest predictive power for future in silico analysis of AVPR1a but none of the VEP programs appear to be accurate for the in silico analysis of AVPR1b variants. NRF-DAAD Physiology MSc (Human Physiology) Unrestricted 2023-02-21T07:12:10Z 2023-02-21T07:12:10Z 2023-03-31 2022 Dissertation * A2023 https://repository.up.ac.za/handle/2263/89707 https://doi.org/10.25403/UPresearchdata.22127099 en © 2022 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
G protein-coupled receptors
Oxytocin receptor
Arginine vasopressin receptor 1a and 1b
Psychological disorders
Birth disorders
Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title_full Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title_fullStr Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title_full_unstemmed Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title_short Functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
title_sort functional characterisation of gene variants of oxytocin and vasopressin receptors implicated in psychological disorders
topic UCTD
G protein-coupled receptors
Oxytocin receptor
Arginine vasopressin receptor 1a and 1b
Psychological disorders
Birth disorders
url https://repository.up.ac.za/handle/2263/89707
https://doi.org/10.25403/UPresearchdata.22127099