miR-329- and miR-495-mediated Prr7 down-regulation is required for homeostatic synaptic depression in rat hippocampal neurons.

Homeostatic synaptic depression (HSD) in excitatory neurons is a cell-autonomous mechanism which protects excitatory neurons from over-excitation as a consequence of chronic increases in network activity. In this process, excitatory synapses are weakened and eventually eliminated, as evidenced by a reduction in synaptic AMPA receptor expression and dendritic spine loss. Originally considered a global, cell-wide mechanism, local forms of regulation, such as the local control of mRNA translation in dendrites, are being increasingly recognized in HSD.

Widespread transcriptional pausing and elongation control at enhancers.

Regulation by gene-distal enhancers is critical for cell type-specific and condition-specific patterns of gene expression. Thus, to understand the basis of gene activity in a given cell type or tissue, we must identify the precise locations of enhancers and functionally characterize their behaviors. Here, we demonstrate that transcription is a nearly universal feature of enhancers in and mammalian cells and that nascent RNA sequencing strategies are optimal for identification of both enhancers and superenhancers.

Modeling Rett Syndrome Using Human Induced Pluripotent Stem Cells.

Rett syndrome (RTT) is one of a group of neurodevelopmental disorders typically characterized by deficits in the X-linked gene MECP2 (methyl-CpG binding protein 2). The MECP2 gene encodes a multifunctional protein involved in transcriptional repression, transcriptional activation, chromatin remodeling, and RNA splicing. Genetic deletion of Mecp2 in mice revealed neuronal disabilities including RTT-like phenotypes and provided an excellent platform for understanding the pathogenesis of RTT.

Connectomics: comprehensive approaches for whole-brain mapping.

The aim of connectomics analysis is to understand whole-brain neural connections. This is accomplished using new biotechnologies. Here, we provide an overview of the recent progress in connectomics analysis.