Translation profiling of epileptogenesis in neurodevelopmental disorders

·        Background

Childhood-onset epilepsy is a feature of several neurodevelopmental disorders, including Fragile X Syndrome and SYNGAP1 haploinsufficiency, two monogenic causes of autism and intellectual disability^1,2. The aetiology of seizures in these disorders is poorly understood. However, treatments that normalize protein synthesis have been shown to prevent the emergence of pathological changes in both Fmr1-/y and Syngap+/- mouse models, including epileptiform activity and susceptibility to audiogenic seizures (AGS) ^3-6. This suggests that dysregulation of protein turnover causes the generation of epilepsy (epileptogenesis) in both disorders.

Identifying the functional consequences of dysregulated protein turnover that contribute to epileptogenesis could provide unique insights and potentially identify new therapeutic targets. The student will use cutting edge techniques in molecular biology, electrophysiology and imaging to assess the functional consequences of changes in protein synthesis and degradation that occur within seizure-generating neurons.

·        About the Project

The specific aims are to: (1) elucidate the critical neuron populations contributing to AGS in Fmr1-/y and Syngap+/- rat models, and (2) to identify the functional changes that occur as a results of dysregulated protein synthesis and degradation in these neurons and that contribute to seizure generation

Although AGS is a highly reproducible phenotype in the Fmr1-/y and Syngap+/- models, the underlying circuitry has not been identified. To identify activated neurons over a time-course post-AGS induction, the student will use a combination of immunostaining for cFos (which reports recently active neurons) and whole-brain imaging. This approach will enable the student to focus on detailed analysis of brainstem nuclei implicated in audiogenic seizures in other models and unbiased brain-wide analyses to capture a global picture of candidate neural populations. The student will then use animals treated with lovastatin, a therapeutic that prevent AGS in the Fmr1-/y model, to more discretely identify the circuits that generate seizure activity ⁴.

To understand how contributes to epileptogenesis, brain slice patch-clamp electrophysiology approaches will be used to identify ion channel mechanisms active in the candidate neuronal populations that lead to seizure generation. This strategy will take advantage of TRAP-seq profiling and proteomic data from the Osterweil lab, which has reveal novel targets for therapeutic intervention in developmental disorders and childhood-onset epilepsies⁷. The initial focus will be on excitatory neurons in the Inferior Colliculus that have been implicated in AGS ⁸. The ion channel mechanisms that promote epileptogenesis in mutant neurons will then be targeted for knock-down using viral injection of shRNAs or using relevant pharmacological strategies.

About the ERUK-DTC

The ERUK-DTC consists of principal investigators from the University of Edinburgh researching childhood-onset epilepsies. In addition to your research, you will be trained and nurtured to become an innovative, creative thinker, will be trained in state of the art techniques, will gain insight into the needs and thoughts of patients and their families, and become equipped to engage with audiences within and beyond the research world. As an ERUK-DTC graduate, you will be ideally placed to be part of the next generation of scientific research leaders in childhood-onset epilepsies. (For more on the ERUK-DTC, see Muir Maxwell Doctoral Training Centre)

About the Supervisors/PI

This project will leverage the experience of two established labs, with complementary strengths in cell type specific translation profiling, electrophysiology whole-brain imaging. The training provided to the student will be well rounded and will include skills in brain clearing, immunostaining, whole-brain imaging analysis, TRAP isolation, and RNA-seq analysis.

 Application procedure

You should hold at least an upper second-class degree or equivalent in a relevant discipline (e.g., cell biology, physiology, neuroscience or related disciplines). Applications should be emailed to [Email Address Removed] and [Email Address Removed] (with “ERUK-PhD” in the subject) including: (i) your CV; (ii) a personal statement (research interests,reasons for applying); (iii) any additional information you would like to be considered e.g., special circumstances/disadvantages faced (optional; 150 word limit). Applicants should also arrange for two academic referees to submit letters of reference via email before the deadline to [Email Address Removed] and [Email Address Removed]. All documents should be submitted no later than 5pm on January 9^th, 2023. Short-listed candidates will be notified by email. Informal enquiries can be sent to [Email Address Removed]