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bioRxiv · 10.1101/2022.04.06.487191

Ectopic insert-dependent neuronal expression of GFAP promoter-driven AAV constructs in adult mouse retina.

Le, N.·Appel, H.·Pannullo, N.·Hoang, T.·Blackshaw, S.
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Abstract

Direct reprogramming of retinal Muller glia is a promising avenue for replacing photoreceptors and retinal ganglion cells lost to retinal dystrophies. However, questions have recently been raised about the accuracy of studies claiming efficient glia-to-neuron reprogramming in retina that were conducted using GFAP mini promoter-driven adeno-associated virus (AAV) vectors. In this study, we have addressed these questions using GFAP mini promoter-driven AAV constructs to simultaneously overexpress the mCherry reporter and candidate transcription factors predicted to induce glia-to-neuron conversion, in combination with prospective genetic labeling of retinal Muller glia using inducible Cre-dependent GFP reporters. We find that, while control GFAP-mCherry constructs express faithfully in Muller glia, 5 out of 7 transcription factor overexpression constructs tested are predominantly expressed in amacrine and retinal ganglion cells. However, genetic cell lineage analysis shows no evidence for glia-to-neuron conversion. These findings demonstrate strong insert-dependent effects on AAV-based GFAP mini promoter specificity that preclude its use in inferring cell lineage relationships when studying glia-to-neuron conversion in retina.

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Le, N., Appel, H., Pannullo, N., Hoang, T., Blackshaw, S.. 2022-04-09. Ectopic insert-dependent neuronal expression of GFAP promoter-driven AAV constructs in adult mouse retina.. https://doi.org/10.1101/2022.04.06.487191

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