Fig. 3

Retinal ganglion cells express MAOB. A The expression levels of the Slc6a3 (encodes the dopamine transporter protein) and Maob (encodes the monoamine oxidase B protein) genes were explored in single-cell RNA-sequencing data from mouse retina. Slc6a3 is only expressed in amacrine cell cluster 1 (likely containing dopaminergic amacrine cells) suggesting that other retinal cells do not uptake MPP+ . Maob is most abundantly expressed in fibroblasts, retinal ganglion cells and vascular endothelium cells, suggesting a direct route for retinal ganglion cells to internally process MPTP to MPP+. This is supported by expression levels of MAOB in B single-cell RNA-sequencing and C single-nucleus RNA sequencing data from human retina, showing that MAOB is expressed in multiple retinal ganglion cell clusters