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. Overall design: 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.