Targeting Müller Cells for Gene Therapy
Retinal support cells such as Müller cells and RPE are excellent candidates for targeting gene therapy vectors. However, the lack of knowledge of gene regulatory mechanisms in Müller cells has limited their use for designing cell type-specific expression vectors for gene therapy. As a first step in this direction, our recent research has focused on the identification of genetic regulatory elements for two Müller cell-specific genes—the glial intermediate filament protein (GFAP) gene and the cellular retinaldehyde-binding protein (CRALBP) gene. Experimental evidence from transfection assays suggest that promoter-proximal sequences are sufficient to drive expression of GFAP and CRALBP genes in Müller cells. However, studies with GFAP-transgenic mice suggest that GFAP gene transcription in Müller cells is complex, and that an inducible, Müller cell-specific enhancer is likely to control GFAP expression. Identification of the enhancer should provide a inducible, promoter system for expressing foreign proteins in the retina.
KeywordsGlial Fibrillary Acidic Protein Retinal Degeneration Mouse Retina Glial Fibrillary Acidic Protein Expression Gene Regulatory Mechanism
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