RESETTING AND SCULPTING THE NOTCH RESPONSE

Lead Research Organisation: University of Cambridge
Department Name: Physiology Development and Neuroscience

Abstract

Communication between cells, the building blocks of the body, is essential to build and maintain our tissues. Failures in this communication are the cause of many diseases, especially many types of cancers. One key way cells communicate is via the Notch receptor. When a signal is received by Notch, the instructions are interpreted differently depending on the previous history of the cell. For example, whether or not a cell will go on to multiply will be based on how its genome is set up to receive the signal. Under normal conditions there are checks and balances in the system to ensure that the cells respond correctly. However, in several types of cancers Notch signalling doesn't function properly. In many of these conditions, including T-cell acute lymphoblastic leukaemia and breast cancers, too much signal is produced causing the cells to multiply excessively, forming tumours. Surprisingly, in some other types of cancer the converse is the case. This makes it important to know how the cells will be interpreting the Notch signal in a particular tissue context. It also makes it more difficult to use drug treatments that simply shut off the Notch signal as they could have damaging effects in some tissues.

By answering two key questions we will acquire a better understanding of cell circumstances that will increase the probability that Notch activity will be oncogenic. This information will be valuable in working out the best strategies for patient treatments and to identify avenues that could be used to develop targeted drugs or drug combinations to avoid problems with current treatments. First we aim to discover what normally resets the way that cells interpret Notch signals, to ensure that they do not behave inappropriately by dividing unchecked and becoming cancer stem cells. Second, we will find out what architectural features of the genome help guide the signal so that the right types of product are made when the genes are turned on. To do this we will use both the fruit fly and human cells and will use strategies that enable us visualize in real time the way the genome is reset to help Notch to pick out which genes to turn on and to find the components in cells that facilitate this. We will also undertake large-scale analysis that allows us to detect global changes in the genome architecture in normal tissue and in tissues that grow too much because they have extra Notch activity. We use fruit flies because they have a simpler system that we can easily study in the living organism, making it more straightforward to decipher the information, yet they have over 75% of the human disease-causing genes. We then translate our discoveries from fruit-flies into the more complex human cancer cells to show their relevance for disease and to identify the best routes towards uses in the clinic.

Technical Summary

The highly conserved Notch signalling pathway functions in diverse developmental and homeostatic processes. Likewise, disease implications from aberrant Notch programmes differ depending on the tissue: Notch activity promotes tumourigenesis in many contexts, including T-cell acute lymphoblastic leukaemia and breast cancers, whereas in others it is protective. Discovering how the appropriate responses to Notch are configured is therefore vital for deciphering when combinations of genetic abnormalities are likely to be oncogenic, and for informing strategies for targeted therapies. Our goal is to use a combination of live-imaging, genetic, biochemical and genomic approaches in Drosophila and in human cells to discover the fundamental mechanisms that reset and sculpt transcriptional responses to Notch. These mechanisms are essential to bring about different outcomes and to avoid inappropriate gene expression programmes being turned on. We have two major aims: (1) to discover what mechanisms ensure that enhancers are correctly remodelled during cell state transitions so that appropriate responses to Notch signals occur and emergence of cancerous cells is avoided; and (2) to learn how Notch-regulated enhancers select and communicate with promoters to produce RNA isoforms with the right regulatory features for the physiological context.

Our results will uncover general principles that explain how the diverse effects of Notch activation arise in tissue development They will also provide important insights for distinguishing the likelihood that disrupted Notch signalling will be oncogenic, by helping to decode contexts where other mutations will affect key components or regulatory mechanisms and will provide new paradigms to aid design of therapeutic strategies.

Planned Impact

Beneficiaries:
-Industry involved in pharmaceutical research and drug development.
-Medical profession involved in treating Notch related diseases including cancers
-Business, industrial and public sector recruiting graduate level staff.
-The general public and schools, through our involvement in public engagement.

Benefits to industry will come from the scientific results and the methodologies we develop:
Notch pathway is a major target for cancer and other therapeutics. Increased knowledge about the mechanisms can lead to novel approaches for targeting the pathway and can be important in informing about unforeseen side effects. For example, our results can inform whether patient mutations could be synergistic with Notch in a particular disease context and/or causing very different outcomes (e.g. tumour promoting versus tumour suppressing). They could also identify novel protein:protein interactions that would be a good substrate for drug developments.
Benefit is likely to be realized in the longer term and it would impact especially on enhancing quality of health.

Benefits to medicine will come from the scientific results and the insights into clinically relevant mechanisms:
A better understanding of how different targets are selected could be extremely valuable in diagnostic strategies because classical Notch targets (e.g., HES1) do not necessarily appear to be modulated in patient tissues. Results will also suggest new possibilities to improve on therapies targeting the Notch pathway. Currently, the main strategies use small molecule inhibitors of gamma-secretase and have serious side effects such as goblet cell metaplasia, as well as off target effects. The discovery of novel regulatory mechanisms in a subset of tissues could lead to strategies for developing more targeted therapies to overcome these problems. They can also be harnessed to manipulate Notch for directed differentiation of stem cells.

Benefits to business, industrial and public sector recruiting graduate level staff will come from the development of relevant research sills and professional skills:
The project's diverse nature ensures that the staff will acquire a broad range of technical skills (high-end imaging, genomic and molecular biology techniques, computational approaches for working with large data sets and modelling), which will be applicable in wide range of life sciences, pharmaceutical, computational employment. Further gains come from our international collaborations, enhancing the skills training and exposure. Alongside technical skills, staff will at the same time develop generic professional skills e.g. presentational skills; writing skills; data handling, including statistics; generic computational skills; project management. Evidence of our track record in this aspect comes from subsequent employment of staff from our groups (e.g. investment banking, parliamentary advisor, publishing, venture capital advisor).

Benefits to the general public and schools, through our involvement in public engagement:
We have been involved in communicating modern scientific ideas, methodologies and approaches to the wider community. These activities will be extended to encourage scientific understanding and to extend the concepts from our research into other fields. The University of Cambridge provides excellent support for public dissemination of research through the Office of Community Affairs, including the Cambridge Science Festival, and we will continue to encourage our researchers to participate in these activities.

Publications

10 25 50
 
Description Herchel Smith Post-Doctoral Fellowship
Amount £150,000 (GBP)
Organisation University of Cambridge 
Sector Academic/University
Country United Kingdom
Start 08/2022 
End 09/2025
 
Description International Exchanges 2023 Round 1
Amount £5,000 (GBP)
Funding ID International Exchanges 2023 Round 1 - IESR1231193 
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 06/2023 
End 12/2023
 
Title Live imaging of endogenous gene transcription 
Description Endogenous Notch target genes have been tagged with MS2-loops to make possible live imaging of transcription in real time in vivo (E(spl)m7 and E(spl)m8) 
Type Of Material Technology assay or reagent 
Year Produced 2021 
Provided To Others? No  
Impact New data sets generated that provide novel insights. Currently under analysis for future publication 
 
Title OptICNocth 
Description Method to produce active Notch using light. 
Type Of Material Technology assay or reagent 
Year Produced 2023 
Provided To Others? Yes  
Impact Used to manipulate Notch activity in vivo and show memory of previous sugnal occurs, https://www.biorxiv.org/content/10.1101/2023.08.10.552629v2 
 
Title MS2 data from "Notch-dependent and -independent transcription are modulated by tissue movements at gastrulation" 
Description MS2 data from "Levels of Notch-regulated transcription are modulated by tissue movements at gastrulation": - raw MS2 Live imaging movies: 123 '.lif' files captured in a Leica SP8 confocal. Each is a 1-2h movie of a developing fly embryo in the genetic condition described in the file name. The metadata file contains the information linking each movie with parameters used for image analysis and identifier of the genetic condition ("nickname" column). - data obtained from image analysis: 123 '.mat' files obtained from MATLAB after image analysis for each movie. README contains information of the data structure and all variables stored in each. - numerical data used for figures: text files containing data points used in all figures in the paper. "NumericalData.txt" contains the information about each plot, axes, figure where it's used and name of the file containing the numerical data. 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL https://figshare.com/articles/dataset/Data_from_Notch-dependent_and_-independent_transcription_are_m...
 
Title Other data from "Notch-dependent and -independent transcription are modulated by tissue movements at gastrulation" 
Description Other live imaging data from "Levels of Notch-regulated transcription are modulated by tissue movements at gastrulation": - raw MS2 Live imaging movies: 58 '.lif' files captured in a Leica SP8 confocal. Each is a 1-2h movie of a developing fly embryo in the genetic condition described in the file name. The metadata file contains the information linking each movie with parameters used for image analysis and identifier of the genetic condition ("nickname" column). - data obtained from image analysis: 57 '.mat' files obtained from MATLAB after image analysis for each movie. README contains information of the data structure and all variables stored in each. 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL https://figshare.com/articles/dataset/Other_data_from_Notch-dependent_and_-independent_transcription...
 
Description CSL Dynamics 
Organisation University of Cincinnati
Country United States 
Sector Academic/University 
PI Contribution Formulated the hypothesis and carrying out the in vivo experiments
Collaborator Contribution Providing structural advice and making biophysical measurements
Impact Is multidisciplinary, collaborator is a structural biologist.
Start Year 2014
 
Description Locus Tag 
Organisation Paul Sabatier University (University of Toulouse III)
Country France 
Sector Academic/University 
PI Contribution Developing locus-tag method for labelling unique gene loci in vivo
Collaborator Contribution Providing the basic strains and plasmids to enable the research
Impact Manuscripts currently under preparation will include methods paper
Start Year 2016
 
Description Notch targets in cancer 
Organisation Cancer Research UK Cambridge Institute
Country United Kingdom 
Sector Academic/University 
PI Contribution Provided enabling data from our research, provided technical assistance and training
Collaborator Contribution comparisons with clinical array data
Impact helped train clinical fellow in molecular techniques likely to yield future publications contributed to proposal for G0800034
Start Year 2007
 
Description Notch targets in neuroblasts 
Organisation Foundation for Research and Technology Hellas (FORTH)
Department Institute of Molecular Biology and Biotechnology (IMBB)
Country Greece 
Sector Academic/University 
PI Contribution Provided the expertise and resources for analysis of Notch targets in neuroblasts
Collaborator Contribution Provided samples for the study
Impact EMBO Short term fellowship for Evanthia Zacharioudaki Notch targets in neuroblasts, data will be cross-referenced and integrated with other data sets we have generated. Led to Dr Zacharioudaki joining the group as a post-doc and to two substantial publicatons. These acheievements underpinned her success in winning follow on funding with an intermediate fellowship in Greece. Zacharioudaki E, Housden BE, Garinis G, Stojnic R, Delidakis C, Bray SJ (2016) Genes implicated in stem-cell identity and temporal-program are directly targeted by Notch in neuroblast tumours. Development 143 (2), pp. 219-231 Zacharioudaki E, Housden BE, Garinis G, Stojnic R, Delidakis C, Bray SJ (2016) Genes implicated in stem-cell identity and temporal-program are directly targeted by Notch in neuroblast tumours. Development 143 (2): 219-231
Start Year 2010
 
Description Africans in STEM Symposium 2022 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Africans in STEM Symposium has the mission to build a network for African scientists. The symposium is an opportunity for African researchers in STEM fields across the UK to connect, share ideas, learn and form collaborations. The symposium welcomes STEM researchers at all levels of expertise - from undergraduates to principal investigators.
Year(s) Of Engagement Activity 2022
URL https://www.africansinstem.co.uk/
 
Description Science Improvisation 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact A group of scientists ranging from PhD students to postdocs, interested in how improv can offer a fun and innovative way to communicate science. They perform shows at festivals and host monthly jam-sessions, and run improv workshops and social events across the university.
Year(s) Of Engagement Activity 2022
URL http://cusi.soc.srcf.net/shows/