Diverse serotonin 2C receptor mediated behaviours resulting from snoRNA regulated post-transcriptional modification

Lead Research Organisation: Cardiff University
Department Name: School of Medicine

Abstract

Chemical signaling in the brain is highly dependent on specific neurotransmitter receptors. Different physical forms (isoforms) of these receptors can dramatically affect neurotransmitter signaling. One of the receptors to which the neurotransmitter serotonin binds, the 2C receptor (5HT2CR) exists in numerous different forms (isoforms) which have varying levels of functionality. The abundance of different 5HT2CR isoforms is dependent on the degree of subtle molecular changes known as post-transcriptional modifications. Preliminary studies have shown that when the regulation of post-transcriptional modification is altered and less functional forms of the receptor are generated, this can lead to behavioural effects that are specific to the function of the 5HT2CR. However, 5HT2CRs regulate many aspects of behaviour and the extent to which these molecular changes and the subsequent receptor variants contribute to different behavioural processes is still not fully understood. The proposed project aims to address this by looking at how the degree of post-transcriptional modification of 5HT2CRs varies through the brain and link these molecular findings to effects on behaviour. To do this we will examine animals lacking an important regulatory component of the post-transcription modification machinery. Our work will lead to a better understanding of how different versions of 5HT2CRs function in brain and may translate into better therapies for clinical conditions such as depression, suicide and schizophrenia, which have been linked to alterations in this receptor.

Technical Summary

In vitro studies suggest the functional efficacy of serotonin 2C receptors (5HT2CR) in brain can be dramatically altered by post-transcriptional modifications of the Htr2c gene pre-RNA. At present we know very little about the normal, physiological regulatory mechanisms controlling post-transcriptional modifications (RNA-editing and alternate splicing) of Htr2c in brain in vivo, and almost nothing about the precise behavioural effects of interfering with these processes. In this context, we recently published the first evidence showing that the exclusively brain expressed imprinted small nucleolar (sno)RNA, Snord115, physiologically regulates the degree of editing of the Htr2c pre-RNA in mouse brain and that this editing modification can lead to highly specific effects on 5HT2CR-mediated behaviour. We focused on Snord115 because this snoRNA (and its human equivalent, SNORD115) is the only known gene containing a recognition sequence for the edited region of the Htr2c pre-RNA, and there is evidence from in vitro studies that Snord115 negatively modulates post-transcriptional modification both in terms of editing and alternate splicing such that the expression of this snoRNA tends to maintain the more functionally active 5HT2CR protein isoforms. We want to investigate the relevance of these in vitro findings to functioning in the whole animal by examining behaviour in animals lacking Snord115. We will focus on established effects of 5HT2CR function on response control and feeding, using molecular and neurobiological evidence to directly link any behavioural changes we observe to Snord115 mediated post-transcriptional modifications of Htr2c pre-RNA. The strong likelihood is that both RNA editing and alternate splicing are important molecular mechanisms contributing to the ways in which efficacy of 5HT2CR neurotransmission remains sensitive to changing environmental conditions and that abnormal functioning contributes to behavioural disorders and psychopathology.

Planned Impact

The proposed research will generate new knowledge that will be of practical use to understanding how serotonin 2C receptors (5HT2CR) function in the brain and how they may go wrong in brain disorders.

Who will benefit from this research, and how?

5HT2CRs play key roles in the regulation of brain function and behaviour and have been shown to be involved in the pathogenesis of a number of common brain disorders, including anxiety, depression and eating abnormalities. Consequently,
5HT2CRs have attracted intense scrutiny as targets for therapeutics but the drugs developed for clinical use have thus far not been optimal. A main benefit of the present basic research, therefore, will be to exploit novel findings about the way post-transcriptional modifications of the gene coding for the 5HT2CR, Htr2c, impacts on the diversity of serotonergic action in the mammalian brain; and thereby assess their likely involvement in 5HT2CR dysfunction. In short, our research on editing and alternate splicing of Htr2c pre-RNA, which was instigated via collaboration with the pharmaceutical company GlaxoSmithKline, may lead to better drugs for patients. As a result, the scope and reach of the work will extend to both UK plc and the general public.

How will the users be engaged?

Dr Anthony Isles has extensive experience of communicating with the general public through podcasts recorded for Nature and the local and national press. He has also regularly been asked to address non-specialised scientists and lay audiences (Science and Philosophy Cafes, to NACWOs and Veterinary groups). Both investigators will continue with these public engagement activities.

Prof Lawrence Wilkinson has close links with a number of pharmaceutical companies, including GSK, who as noted above have direct interest in the proposed work. Wilkinson is a founder member of the Lilly Centre for Cognitive Neuroscience and the P1vital Ltd (Oxford) Experimental Medicine Consortium Academic Panel. Regular meetings and discussions will continue to be held with senior representatives of these and other companies to discuss opportunities for translation of the basic findings into the drug discovery process, and for training opportunities.
 
Description Serotonin is an important chemical in the brain which binds to many receptors. One of these receptors, the serotonin 2C receptor, has many roles. Our findings show that modifications called "editing" and "splicing" to the RNA product that produces the serotonin 2C receptor protein has consequences for behaviour. Moreover, this process is regulated in part by another gene called snord115. Loss of this leads to an animal that shows abnormal feeding and impulse control behaviour, and that is has a differential reaction to drugs that bind to the serotonin 2C receptor. This may provide a novel therapeutic mechanism for modifying serotonin 2C receptor function.
Exploitation Route Development of drugs; further understanding of the biochemical processes that lead to these molecular changes.
Sectors Healthcare,Pharmaceuticals and Medical Biotechnology

 
Description The work associated with this grant has shed light on the molecular mechanisms underpinning the function of a key neurotransmitter receptor, namely the serotonin 2C receptor. This receptor governs many behaviours, including feeding, impulse control and anxiety/depression. Recently data generated under this award, plus data generated under previous funding, attracted the attention of GW Pharamceuticals who were looking for a relevant pre-clinical model of PWS. Moreover, this work attracted the attention of the Foundation for Prader-Willi Research who asked me to join their Pre-Clinical Animal Network with the aim of developing a future pre-clinical platform for testing therapeutics.
First Year Of Impact 2012
Sector Education,Healthcare,Pharmaceuticals and Medical Biotechnology
Impact Types Economic,Policy & public services

 
Description FPWR Pre-Clinical Animal Network
Geographic Reach Multiple continents/international 
Policy Influence Type Participation in a advisory committee
URL http://research.fpwr.org/blog/de-risking-pws-drug-development-through-preclinical-screening
 
Description Examining the effects of four phytocannabinoids (CBD, CBDV, DBDA, THCV (chronic dosing, at a range of doses) on PWS-IC behaviour in a number of tasks
Amount £81,919 (GBP)
Funding ID 20150827 
Organisation GW Pharmaceuticals 
Sector Private
Country United Kingdom
Start 07/2015 
End 03/2018
 
Description Neuronal mechanisms of developmental cognitive impairment in the Snord1 16del model for Prader-Willi Syndrome
Amount £3,300 (GBP)
Organisation Prader-Willi Syndrome Association 
Sector Charity/Non Profit
Country United Kingdom
Start 01/2019 
End 12/2019
 
Description Foundation for Prader-Willi Research "Pre-Clinical Animal Network" (FPWR-PCAN) 
Organisation Foundation for Prader-Willi Research (FPWR)
Country United Kingdom 
Sector Charity/Non Profit 
PI Contribution Our expertise has been used to shape the decision making with regards to animal models to be generated and the phenotyping pipeline.
Collaborator Contribution FPWR facilitated the formation and meetings of the FPWR-PCAN and drove the decision-making MRC Harwell, IIT & INMED helped shape the decision making with regards to animal models to be generated and the phenotyping pipeline
Impact Generation of new PWS mouse models by MRC Harwell - these are underway currently
Start Year 2016
 
Description Foundation for Prader-Willi Research "Pre-Clinical Animal Network" (FPWR-PCAN) 
Organisation Italian Institute of Technology (Istituto Italiano di Tecnologia IIT)
Country Italy 
Sector Academic/University 
PI Contribution Our expertise has been used to shape the decision making with regards to animal models to be generated and the phenotyping pipeline.
Collaborator Contribution FPWR facilitated the formation and meetings of the FPWR-PCAN and drove the decision-making MRC Harwell, IIT & INMED helped shape the decision making with regards to animal models to be generated and the phenotyping pipeline
Impact Generation of new PWS mouse models by MRC Harwell - these are underway currently
Start Year 2016
 
Description Foundation for Prader-Willi Research "Pre-Clinical Animal Network" (FPWR-PCAN) 
Organisation MRC Harwell
Department MRC Mammalian Genetics Unit
Country United Kingdom 
Sector Academic/University 
PI Contribution Our expertise has been used to shape the decision making with regards to animal models to be generated and the phenotyping pipeline.
Collaborator Contribution FPWR facilitated the formation and meetings of the FPWR-PCAN and drove the decision-making MRC Harwell, IIT & INMED helped shape the decision making with regards to animal models to be generated and the phenotyping pipeline
Impact Generation of new PWS mouse models by MRC Harwell - these are underway currently
Start Year 2016
 
Description Foundation for Prader-Willi Research "Pre-Clinical Animal Network" (FPWR-PCAN) 
Organisation National Institute of Health and Medical Research (INSERM)
Department Neurobiology Institute of the Mediterranean
Country France 
Sector Academic/University 
PI Contribution Our expertise has been used to shape the decision making with regards to animal models to be generated and the phenotyping pipeline.
Collaborator Contribution FPWR facilitated the formation and meetings of the FPWR-PCAN and drove the decision-making MRC Harwell, IIT & INMED helped shape the decision making with regards to animal models to be generated and the phenotyping pipeline
Impact Generation of new PWS mouse models by MRC Harwell - these are underway currently
Start Year 2016
 
Description GW Pharmaceuticals 
Organisation GW Pharmaceuticals
Country United Kingdom 
Sector Private 
PI Contribution Using data acquired under previous grants to guide research into potential therapeutics
Collaborator Contribution Providing therapeutics (subject to confidentiality agreement) for testing
Impact Research contract funding
Start Year 2015
 
Description GW4 epigenetics consortium 
Organisation Cardiff University
Country United Kingdom 
Sector Academic/University 
PI Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Collaborator Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Impact Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Commitment to apply for GW4 Accelerator funding to establish an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Initiator fund
Start Year 2014
 
Description GW4 epigenetics consortium 
Organisation University of Bath
Department Department of Biology and Biochemistry
Country United Kingdom 
Sector Academic/University 
PI Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Collaborator Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Impact Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Commitment to apply for GW4 Accelerator funding to establish an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Initiator fund
Start Year 2014
 
Description GW4 epigenetics consortium 
Organisation University of Bristol
Country United Kingdom 
Sector Academic/University 
PI Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Collaborator Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Impact Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Commitment to apply for GW4 Accelerator funding to establish an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Initiator fund
Start Year 2014
 
Description GW4 epigenetics consortium 
Organisation University of Exeter
Country United Kingdom 
Sector Academic/University 
PI Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Collaborator Contribution Overview of Research Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Discussion of establishing an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Accelerator fund
Impact Discussion of proposal for GW4 Epigenetics consortium doctoral training scheme, how this would be structured and where to go for further funding. Commitment to apply for GW4 Accelerator funding to establish an "GW4 Epigenetics club" for junior scientists to discuss research; application for this from the GW4 Initiator fund
Start Year 2014
 
Description Estonian PWS society - carers, patients and parents lecture 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Type Of Presentation keynote/invited speaker
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact A lay talk to carers, parents and individuals with Prader-Willi syndrome, organised by the Estonian PWS Society. The talk was entitled:

"What can animals tell us about Prader-Willi syndrome?"

no actual impacts realised to date
Year(s) Of Engagement Activity 2012
 
Description FPWR-PCAN 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Supporters
Results and Impact Participation in the Foundation for Prader-Willi Research "Pre-clinical animal network" (PCAN), an expert group advising the charity in relation to its strategy for developing and using animal models to test novel therapeutics
Year(s) Of Engagement Activity 2016,2017,2018
 
Description IPWSO meeting 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact PhD student Simona Zahova attended and present at the IPWSO meeting in Cuba.
Year(s) Of Engagement Activity 2019
 
Description Invited research talk at ASPET/EB 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Invited to give a research talk at the American Society of Pharmacology and Experimental Therapeutics/Experimental Biology conference in Boston, Mass. April 24 2013. The title of the symposium was:

The 5-HT2C receptor: A new target for multiple therapeutics

no actual impacts realised to date
Year(s) Of Engagement Activity 2013
URL http://www.aspet.org/EB2013/
 
Description PWS Estonia (scientific lecture) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Type Of Presentation keynote/invited speaker
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact A lecture to the clinicians and research scientists who are part of the Prader-Willi Association of Estonia Estonian Prader-Willi society. The talk discussed the work underpinned by this funding and was entilted:

"The effect of Htr2c post-transcriptional modification on 5-HT2C receptor regulated behaviour in a model of PWS" None

no actual impacts realised to date
Year(s) Of Engagement Activity 2012
 
Description Research talk to the Society for the Study of Behavioural Phenotypes 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact International meeting (held in the Netherlands) attended by scientists, clinicians and students. Research seminar sparked much discussion afterwards.
Year(s) Of Engagement Activity 2017
URL http://www.ssbpconference.org/2017/index.html
 
Description Society for Neuroscience Poster presentation 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact 10 people independently visited a poster presentation by Jennifer Davies that included detailed discussion.
Year(s) Of Engagement Activity 2014