The role of moonlighting proteins in neurogenesis

The complexity of the mammalian brain must arise from a comparably small number of genes. Proteins with moonlighting functions, i.e. entirely different functions in different compartments or cell types, contribute to multiply functional diversity. Here we review examples of such proteins with moonlighting functions during neurogenesis and in neuronal maturation. These range from cytoskeletal proteins acting as transcriptional regulators or synaptic proteins or exon junction proteins binding to and regulating the cytoskeleton to immediate early gene transcription factors regulating lipid metabolism in the endoplasmic reticulum. We further discuss how proteins with such moonlighting functions contribute to the heterogeneity of organelles shaping cell-type diversity in the brain.