A Primate lncRNA Mediates Notch Signaling During Neuronal Development by Sequestering miRNA [single cell sequencing analysis]

Long non-coding RNAs (lncRNAs) are a diverse category of transcripts with poor conservation and have expanded greatly in primates, particularly in their brain. We identified a lncRNA, which has acquired 16 microRNA response elements (MREs) for miR-143-3p in the Catarrhini branch of primates. This lncRNA termed LncND (neuro-development) gets expressed in neural progenitor cells and then declines in mature neurons. Binding and release of miR-143-3p, by LncND, can control the expression of Notch. Its expression is highest in radial glia cells in the ventricular and outer subventricular zones of human fetal brain. Down-regulation of LncND in neuroblastoma cells reduced cell proliferation and induced neuronal differentiation, an effect phenocopied by miR-143-3p over-expression and supported by RNA-seq analysis. These findings support a role for LncND in miRNA-mediated regulation of Notch signaling in the expansion of the neural progenitor pool of primates and hence contributing to the rapid growth of the cerebral cortex. Cerebral organoids were generated as in Lancaster et al. (Lancaster and Knoblich, 2014). Organoids were dissociated into single cells and captured on C1 Single-Cell Auto Prep Integrated Fluidic Circuit (IFC) (Fluidigm). The RNA extraction and amplification was performed on the chip as described by the manufacturer. We captured 68 single-cells on a C1 Single-Cell Auto Prep System (Fluidigm) and sequenced the RNA on a NextSeq500 System (Illumina) (Pollen et al., 2014). Out of 68 cells, we obtained 60 high quality cells.