Paralog factors are considered to ensure the robustness of biological processes by providing redundant activity in cells where they are co-expressed. However, the specific contribution of each factor is frequently underestimated. In the developing spinal cord, multiple families of transcription factors successively contribute to differentiate an initially homogenous population of neural progenitors into a myriad of neuronal subsets with distinct molecular, morphological, and functional characteristics.
View Article and Find Full Text PDFLong-range enhancer interactions critically regulate gene expression, yet little is known about how their coordinated activities contribute to CNS development or how this may, in turn, relate to disease states. By examining the regulation of the transcription factor NFIA in the developing spinal cord, we identified long-range enhancers that recapitulate NFIA expression across glial and neuronal lineages in vivo. Complementary genetic studies found that Sox9-Brn2 and Isl1-Lhx3 regulate enhancer activity and NFIA expression in glial and neuronal populations.
View Article and Find Full Text PDFDuring development, two cell types born from closely related progenitor pools often express identical transcriptional regulators despite their completely distinct characteristics. This phenomenon implies the need for a mechanism that operates to segregate the identities of the two cell types throughout differentiation after initial fate commitment. To understand this mechanism, we investigated the fate specification of spinal V2a interneurons, which share important developmental genes with motor neurons (MNs).
View Article and Find Full Text PDFMicroRNAs (miRNAs) are 20-25 nucleotide long, noncoding, and single-strand RNAs that have been found in almost all organisms and shown to exert essential roles by regulating the stability and translation of target mRNAs. In mammals most miRNAs show tissue specific and developmentally regulated expression. Approximately 70 % of all miRNAs are expressed in the brain and a growing number of studies have shown that miRNAs can modulate both brain development function and dysfunction.
View Article and Find Full Text PDFIn the absence of external stimuli, the mammalian neocortex shows intrinsic network oscillations. These dynamics are characterized by translaminar assemblies of neurons whose activity synchronizes rhythmically in space and time. How different cortical layers influence the formation of these spontaneous cellular assemblies is poorly understood.
View Article and Find Full Text PDFMicroRNAs (miRNAs) are rapidly emerging as a new layer of regulation of mammalian brain development. However, most of the miRNA target genes remain unidentified. Here, we explore gene expression profiling upon miRNA depletion and in vivo target validation as a strategy to identify novel miRNA targets in embryonic mouse neocortex.
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