Coupling transcriptome with electrophysiology analyses of human Rett syndrome neurons

Funding Type: 
Basic Biology V
Grant Number: 
RB5-07481
Investigator: 
ICOC Funds Committed: 
$0
Public Abstract: 
The iPSC technology has made it possible to establish patient-specific neurological “disease-in-a dish” models. However, the enormous heterogeneity and variations of the system need to be taken into consideration while utilizing this approach for studying disease mechanisms and/or drug discovery. Unfortunately, with the current differentiation protocol to form functional neural circuits from iPSC-derived neurons, we have very little control over the types and the composition of functionally active circuitries that are formed in culture. We have been studying one of the Autism Spectrum Disorders, Rett syndrome (RTT), by utilizing RTT iPSC-derived neurons. We found that the phenotype in spontaneous neural transmission from control and mutant neurons is difficult to track, because the phenotype is highly dependent on the nature of the circuitry. We hypothesize that one way to circumvent the circuitry-dependent problem of RTT neurons is to perform phenotype analysis via electrophysiology recordings followed by genome-wide transcriptome analysis at the single cell stage. In this application, we will perform recordings and single neuron transcriptome analyses from wild type and mutant RTT neurons. Furthermore, we will use Prox1 to induce hippocampal dentate gyral granule neurons and study electrophysiology paired with single neuron transcriptome analyses in vitro, as well as in vivo, after transplantation and integration of neurons into recipient SCID mouse brains.
Statement of Benefit to California: 
The introduction of iPSC technology has made it possible to establish patient-specific neurological “disease-in-a dish” models to study disease mechanisms and drug discovery. Prior to utilizing these models, it is crucial to solve issues such as heterogeneity and variations within the system, since with the current differentiation protocols to form functional neural circuits from iPSC-derived neurons, we have very little control over the types and the composition of functionally active circuitries that are formed in culture. Using one of the Autism Spectrum Disorders, Rett syndrome (RTT), as a model, we aim to circumvent the circuitry-dependent problem of RTT neurons by performing phenotype analysis via electrophysiology recordings followed by genome-wide transcriptome analysis at the single cell level. Our proposed studies will help us understand the genetic and functional mechanisms underlying diseased neural circuitries, and our results will shed light on the nature of the formation of healthy neural networks. The number of residents of California suffer from diseases that could potentially be cured by stem cell-based therapies. In order to be able to use iPSCs as disease models or for therapy purposes, better understanding of their differentiation, as well as function of their progeny, is required. The information obtained from the results of this proposal will benefit the residents of California with respect to stem cell therapy and the use of iPSCs as disease models.

© 2013 California Institute for Regenerative Medicine