James Briscoe & Robin Lovell-Badge

 

Normal and Disturbed Gene Regulatory Networks in Neural Stem Cells and Brain Tumours   

NOTE:

Non-EU applicants are not eligible for the funding for this project.

Neural stem cells, distributed throughout the embryonic brain and located in restricted regions of the adult brain, are responsible for generating new neurons and glial cells. The behaviour of a neural stem cell - whether it proliferates or differentiates - is dictated by a gene regulatory network, composed of a set of transcription factors and controlled by signalling molecules. This network specifies stem cell fate and determines the rate at which the cells self-renew or differentiate. In healthy individuals, the function of this network ensures the development and maintenance of neural tissue. Dysregulation of the network, however, can lead to tumorigenesis, most notably gliomas - a heterogeneous group of tumours that arise from alterations in the rate of proliferation and differentiation of neural stem cells. Both neural stem cells and stem cells from gliomas can be isolated, cultured and genetically manipulated in the laboratory. Moreover, remarkable recent advances in genome editing technologies, in particular CRISPR/Cas9, are opening up possibilities for a wide range of precise manipulations in these cells. This provides a unique opportunity to identify key components of the neural stem cell gene regulatory network and determine how key factors become deregulated in gliomas.

As part of the CRUK Brain Tumour Accelerator programme, this project will focus on determining the function of two families of neural stem cell-affiliated transcription factors - the NFIA/B and SoxE families. Members of these families are expressed in neural stem cells and gliomas and are associated with the induction and maintenance of stem cell properties. The project will use molecular and genomic techniques, including chromatin immunoprecipitation (ChIP), ATAC-seq, and methods to explore the binding distribution, to detect protein-protein interactions and to determine the regulation and function of these proteins in neural lineages, both during normal development and when deregulated in glioma stem cells. To this end, human embryonic stem cells, neural stem cells and glioma derived stem cells will be constructed using CRISPR Cas gene editing that harbour suitably mutated or tagged versions of the genes. We will also generate cells lines that express fluorescent markers from the endogenous loci and use these to screen and identify the regulatory elements necessarily to drive expression of these genes in neural stem cells. The availability of mouse lines with targeted mutations in members of these gene families also offers the possibility, if appropriate, of performing in vivo experiments to test hypothesis and compare results cross-species. Together these approaches will help define the gene regulatory mechanisms controlling neural stem cells, and how these are altered in glioma stem cells.