ENHANCING THE DEVELOPMENT OF A9 MIDBRAIN DOPAMINERGIC NEUROUS THROUGH TRANSCRIPTION FACTORS AND GLIAL DERIVED NEUROTROPHIC FACTOR

Abstract

The selective loss of A9 midbrain dopaminergic (mDA) neurons is largely responsible for the motor degeneration observed in Parkinson’s disease. While human neural stem cells (hNSCs) hold significant potential for cell replacement therapies aimed at restoration, their use has been greatly hampered by the lack of existing methods in converting them efficiently into A9 mDA neurons. Foreseeing the need to conduct extensive gene expression analysis for the identification of intrinsic determinants in neuron differentiation, a portion of this thesis was dedicated to the development and validation of workflows and tools essential for the examination of transcriptomic changes. We demonstrated the workflow utility in isolating specific neuronal subtypes from a heterogeneous population, which led to identification of a novel transcription factor SOX6 as a molecular driver. Realizing the need to over-express candidate genes effectively, an efficient non-viral gene delivery system was also established. In a separate study, we examined the GFRα receptor isoforms involved in mDA neuron differentiation and discovered that GDNF may mediate it effects through GFRα1a, and transduce signals through RET but not NCAM. Increased knowledge of both intrinsic and extrinsic signaling developmental cues could be translated into novel strategies for the production of A9 mDA neurons in vitro