Project description:The neurobiological functions of a number of kinases expressed in the brain are unknown. Here, we report new findings on DCLK3 (Doublecortin-like kinase 3) which is preferentially expressed in neurons in the striatum and dentate gyrus. Its function has never been investigated. DCLK3 expression is markedly reduced in Huntington's disease. Recent data obtained in studies related to cancer suggest DCLK3 could have anti-apoptotic effect. Thus, we hypothesized that early loss of DCLK3 in Huntington's disease may render striatal neurons more susceptible to mutant huntingtin (mHtt). We discovered that DCLK3 silencing in the striatum of mice exacerbated the toxicity of an N-terminal fragment of mHtt. Conversely, overexpression of DCLK3 reduced neurodegeneration produced by mHtt. DCLK3 also produced beneficial effects on motor symptoms in a knock-in mouse model of Huntington's disease. Using different mutants of DCLK3, we found that the kinase activity of the protein plays a key role in neuroprotection. To investigate the potential mechanisms underlying DCLK3 effects, we studied the transcriptional changes produced by the kinase domain in human striatal neurons in culture. Results show that DCLK3 regulates in a kinase-dependent manner the expression of many genes involved in transcription regulation and nucleosome/chromatin remodeling. Consistent with this, histological evaluation showed DCLK3 is present in the nucleus of striatal neurons and, protein-protein interaction experiments suggested that the kinase domain interacts with zinc finger proteins, including TADA3, a core component of SAGA complex. Our novel findings suggest that the presence of DCLK3 in striatal neurons may play a key role in transcription regulation and chromatin remodeling in these brain cells, and show that reduced expression of the kinase in Huntington’s disease could render the striatum highly vulnerable to neurodegeneration. Examination of DCLK3 as neuroprotector against mutant huntingtin in vivo and in vitro models.
Project description:Purpose: Next-generation sequencing (NGS) technology was used to map expression profile of hippocampal tissue in mouse model of Systemic Lupus Erythematosus (SLE). Methods: Total RNA was extracted from total hippocampal tissue using NucleoSpinRNA and mRNA libraries were generated using the Illumina TruSeq Sample Preparation kit. Single-end 100bp mRNA sequencing was performed on Illumina NextSeq500 platform. Quality of sequencing was assessed using FastQC software. Raw reads in fastq format were collected and aligned to the mouse genome (mm10 version) using STAR 2.6 algorithm. Gene quantification was performed using HTSeq and differential expression analysis was performed using edgeR package. Results: We defined hippocampal-specific molecular signatures of the murine lupus transcriptome. Conclusions: By the use of the mouse hippocampal-specific transcriptome and through characterization of hippocampal neurogenesis, we showed that inflammatory mediators induce neuropsychiatric changes in SLE as an early event via the disruption of hippocampal neurogenesis. These data underscore the role of brain inflammation in the pathogenesis of early disease and support the use of immunosuppressants for the management of diffuse NPSLE.
Project description:Fragile X syndrome (FXS), caused by mutations in fragile X mental retardation 1 gene (FMR1), is a prevailing genetic disorder of intellectual disability and autism. Analysis of transcriptome outcome (differentially expressed genes between WT and Fmr1 KO hippocampal neuron) associated with FXS reveal promising value of gene signature-based computation in repurposing drugs for potential practical treatment.
Project description:To investigate if Fibcd1 mediates CSPG signalling to neurons, we established a primary mouse hippocampal neuron culture plated +/- a coating of CSPGs. After determining that Fibcd1 KO neurons are partially resistant to CSPG signals, we sought to identify the transcriptional finger print of CSPG-Fibcd1 signalling by nulk RNA-seq.
