Human brain development is a process tightly controlled by morphogens and transcription factors in a temporal- and spatial-dependent manner. Dysregulation of these concerted actions can cause altered cellular proliferation and differentiation leading to brain malformation and abnormal brain function. SETBP1 gene is located at 18q12.3 and is associated with several neurodevelopmental disorders. SETBP1 haploinsufficiency due to heterozygous gene deletion or loss-of-function mutation cause SETBP1 haploinsufficiency disorder (HD), a rare disorder with clinical features including expressive language impairment, intellectual disability, autistic-like traits, or attention deficit hyperactivity amongst others. In contrast, point mutations of SETBP1 result in gain-of-function causing a different disorder called Schinzel-Giedion syndrome (SGS). SGS is a severe multi-organ disorder characterized by distinctive facial features, profound neurodevelopmental and structural anomalies and higher prevalence of myeloid leukaemia However, other than its expression in the foetal brain, little is known about the role of SETBP1 in the central nervous system.
To decipher the role of SETBP1 in brain development and mimic the effect of the gene deletion, we generated several SETBP1-deficient human embryonic stem cells (hESCs) using CRISPR/Cas9 assisted genome editing technology. Using an in vitro neuronal differentiation paradigm, we observed that the SETBP1-deficient cells exhibited a strong phenotype that differs from the parental control cells. We found alterations in several aspects related to Radial glia (RG) proliferation and neurogenesis, which could to some extent explain the clinical phenotype observed in patients with SETBP1 haploinsufficiency.
To better recapitulate features of early to mid brain human embryonic development we aim to optimize a 3D culture or organoids model for SETBP1 disorder in vitro modelling. Several studies using organoid models have proved the usefulness of this 3D culture in the context of neurodevelopmental and psychiatric disorders. This 3D culture presents advantages over monolayer cultures such as allowing to study RG cell organization in the ventricular (proliferative) zone and pseudo cortical layers organization. The presence of outer RG is an unique feature of human cortical development that underlies human cortex expansion and its complexity and its has been proved to be better represented in a 3D organoid model.
Moreover, we also aim to study the functional properties of the SETBP1-deficient mature cortical neurons using Multiple Electrode Array technology (MEA). MEA technology provides a non-invasive method for electrical properties evaluation of cell cultures. The neuronal functionality would be analyzed in the basal culture conditions as well as after WNT signaling inhibition using drugs. As the cultures mature over time, neurons form cohesive networks and develop functional network activity, it is expected to observe differences in network activity between the WT parental line and the SETBP1-deficient lines. In parallel, an analysis of neurite branching and synapse would be carried out by analysis of presynaptic and postsynaptic proteins by immunocytochemistry and high throughput imaging analysis.
*Please note that this project can be completed as an MPhil or PhD*
A 1st or Upper 2nd class UK honours degree or equivalent. Please visit School of Biosciences Postgraduate Research for more details.
For those whose first language is not English, IELTS with an overall score of 6.5 with 5.5 in all subskills, or equivalent. Please see our English Language Requirements guidance for more details.
How to Apply
To submit a formal application via Cardiff University’s online application service, click the 'Institution Website' button on this advert; in the ‘Apply’ box at the top-right of the page, select Qualification (Doctor of Philosophy/Master of Philosophy), Mode of Study (Full Time) and Start Date (this can be flexible as it is a self-funded project). This will take you to the application portal.
Candidates must submit the following:
• Supporting statement
• Qualification certificates
• Proof of English language (if applicable)
In the research proposal section of the application, specify the project title and supervisors of the project. In the funding section, specify that you will be self-funding. If you are applying for more than one Cardiff University project with the same entry intake, please note this in the research proposal section as the form only allows you to enter one title.