Long non‐coding RNAs in corticogenesis: deciphering the non‐coding code of the brain

Abstract

Evidence on the role of long non-coding (lnc) RNAs has been accumulating over decades, but it has been only recently that advances in sequencing technologies have allowed the field to fully appreciate their abundance and diversity. Despite this, only a handful of lncRNAs have been phenotypically or mechanistically studied. Moreover, novel lncRNAs and new classes of RNAs are being discovered at growing pace, suggesting that this class of molecules may have functions as diverse as protein-coding genes. Interestingly, the brain is the organ where lncRNAs have the most peculiar features including the highest number of lncRNAs that are expressed, proportion of tissue-specific lncRNAs and highest signals of evolutionary conservation. In this work, we critically review the current knowledge about the steps that have led to the identification of the non-coding transcriptome including the general features of lncRNAs in different contexts in terms of both their genomic organisation, evolutionary origin, patterns of expression, and function in the developing and adult mammalian brain.

Human-specific genomic signatures of neocortical expansion

“…Non-coding loci recently implicated in cortical expansion include long non-coding RNAs (lncRNAs), increasingly under investigation for their role in regulating gene expression during neurogenesis [36 , [62][63][64]. LncRNAs comprise up to 58 000 genes in humans.…”

“…LncRNAs comprise up to 58 000 genes in humans. Especially in the brain, lncRNAs are produced in extraordinary number and diversity, with regionally segregated expression patterns [62]. Notably, many lncRNAs are enriched in specific subpopulations of neocortical cells, including RG subtypes [36 , 63,64].…”

Post‐transcriptional regulation of gene expression in neural stem cells

“…LncRNAs are involved in transcriptional and post‐transcriptional regulations of gene expression, contributing to proper development, cellular function, and cell fate decisions . Although several brain‐enriched lncRNAs have been shown to be required for neural system development, most of them show a regulatory role in transcription . For example, the neural‐specific lncRNA RMST has been reported to regulate neurogenesis through cooperation with Sox2; the interaction between RMST and Sox2 influences gene expression in neurogenesis (Table ).…”

Long Noncoding RNA BCYRN1 Promotes the Proliferation of Colorectal Cancer Cells via Up-Regulating NPR3 Expression

“…LncRNAs are evolutionarily conserved ncRNAs with more than 200 nucleotides in length and no protein-coding capacity [11,12]. Emerging evidence has shown that lncRNAs are implicated in multiple cellular biological processes, and several lncRNAs have been reported to be involved in CRC progression and tumorigenesis [13][14][15][16].…”