Project description:Laser capture microdissected choroid plexuses were obtained and expression arrays were generated to investigate gene expression in ApoE-Knockin choroid plexuses; the choroid plexus forms the cerebrospinal fluid, the cerebrospinal fliod barrier, functions as the major gateway for blood-born leukocytes to enter the brain in degenerative and inflammatory brain diseases, and the principal neuroimmune interface in the brain. We found lipid deposits in the aged choroid plexus of hyperlipidemic ApoE4-Knockin mice but none in normolipidemic ApoE4-Knockin or normolipidemic or hyperlipidemic ApoE3-Knockin control choroid plexuses. Here, we studied the functional impact and gene epressions these choroid plexuses.
Project description:Myotonic dystrophy type 1 is a dominantly inherited multisystemic disease caused by CTG tandem repeat expansions in the DMPK 3' untranslated region. These expanded repeats are transcribed and produce toxic CUG RNAs that sequester and inhibit activities of the MBNL family of developmental RNA processing factors. Although myotonic dystrophy is classified as a muscular dystrophy, the brain is also severely affected by an unusual cohort of symptoms, including hypersomnia, executive dysfunction, as well as early onsets of tau/MAPT pathology and cerebral atrophy. To address the molecular and cellular events that lead to these pathological outcomes, we recently generated a mouse Dmpk CTG expansion knockin model and identified choroid plexus epithelial cells as particularly affected by the expression of toxic CUG expansion RNAs. To determine if toxic CUG RNAs perturb choroid plexus functions, alternative splicing analysis was performed on lateral and hindbrain choroid plexi from Dmpk CTG knockin mice. Choroid plexus transcriptome-wide changes were evaluated in Mbnl2 knockout mice, a developmental-onset model of myotonic dystrophy brain dysfunction. To determine if transcriptome changes also occurred in the human disease, we obtained post-mortem choroid plexus for RNA-seq from donors without neurologically unaffected (two females, three males; ages 50-70) and myotonic dystrophy type 1 donors (one female, three males; ages 50-70). To test that choroid plexus transcriptome alterations resulted in altered CSF composition, we obtained CSF via lumbar puncture from patients with myotonic dystrophy type 1 (five females, five males; ages 35-55) and non-myotonic dystrophy patients (three females, four males; ages 26-51) and Western blot and osmolarity analyses were used to test CSF alterations predicted by choroid plexus transcriptome analysis. We determined that CUG RNA induced toxicity was more robust in the lateral choroid plexus of Dmpk CTG knockin mice due to comparatively higher Dmpk and lower Mbnl RNA levels. Impaired transitions to adult splicing patterns during choroid plexus development were identified in Mbnl2 knockout mice, including mis-splicing previously found in Dmpk CTG knockin mice. Whole transcriptome analysis of myotonic dystrophy type 1 choroid plexus revealed disease-associated RNA expression and mis-splicing events. Based on these RNA changes, predicted alterations in ion homeostasis, secretory output, and CSF composition were confirmed by analysis of myotonic dystrophy type 1 CSF. Our results implicate choroid plexus spliceopathy and concomitant alterations in CSF homeostasis as an unappreciated contributor to myotonic dystrophy type 1 CNS pathogenesis.
Project description:Myotonic dystrophy type 1 is a dominantly inherited multisystemic disease caused by CTG tandem repeat expansions in the DMPK 3' untranslated region. These expanded repeats are transcribed and produce toxic CUG RNAs that sequester and inhibit activities of the MBNL family of developmental RNA processing factors. Although myotonic dystrophy is classified as a muscular dystrophy, the brain is also severely affected by an unusual cohort of symptoms, including hypersomnia, executive dysfunction, as well as early onsets of tau/MAPT pathology and cerebral atrophy. To address the molecular and cellular events that lead to these pathological outcomes, we recently generated a mouse Dmpk CTG expansion knockin model and identified choroid plexus epithelial cells as particularly affected by the expression of toxic CUG expansion RNAs. To determine if toxic CUG RNAs perturb choroid plexus functions, alternative splicing analysis was performed on lateral and hindbrain choroid plexi from Dmpk CTG knockin mice. Choroid plexus transcriptome-wide changes were evaluated in Mbnl2 knockout mice, a developmental-onset model of myotonic dystrophy brain dysfunction. To determine if transcriptome changes also occurred in the human disease, we obtained post-mortem choroid plexus for RNA-seq from donors without neurologically unaffected (two females, three males; ages 50-70) and myotonic dystrophy type 1 donors (one female, three males; ages 50-70). To test that choroid plexus transcriptome alterations resulted in altered CSF composition, we obtained CSF via lumbar puncture from patients with myotonic dystrophy type 1 (five females, five males; ages 35-55) and non-myotonic dystrophy patients (three females, four males; ages 26-51) and Western blot and osmolarity analyses were used to test CSF alterations predicted by choroid plexus transcriptome analysis. We determined that CUG RNA induced toxicity was more robust in the lateral choroid plexus of Dmpk CTG knockin mice due to comparatively higher Dmpk and lower Mbnl RNA levels. Impaired transitions to adult splicing patterns during choroid plexus development were identified in Mbnl2 knockout mice, including mis-splicing previously found in Dmpk CTG knockin mice. Whole transcriptome analysis of myotonic dystrophy type 1 choroid plexus revealed disease-associated RNA expression and mis-splicing events. Based on these RNA changes, predicted alterations in ion homeostasis, secretory output, and CSF composition were confirmed by analysis of myotonic dystrophy type 1 CSF. Our results implicate choroid plexus spliceopathy and concomitant alterations in CSF homeostasis as an unappreciated contributor to myotonic dystrophy type 1 CNS pathogenesis.
Project description:The aim of the study was to investigate hepatic gene expression profiles differentially regulated by the APOE genotype in gene targeted replacement mice. The APOE4 genotype is associated with increased mortality in the elderly and is an independent risk factor for age-dependent chronic diseases. However, little is known about the underlying mechanisms and molecular targets involved in the APOE4-risk association. As APOE is centrally involved in lipid and cholesterol metabolism and in large part is produced in the liver, we analyzed hepatic RNA profiles of APOE4- and APOE3-expressing mice. 2 groups of 5 animals with 1 liver extract per animal. Mice were homozygous for a human APOE3 or APOE4 gene targeted replacement of the endogenous mouse Apoe gene (B6.129P2-Apoetm2(APOE*3)Mae N8 or B6.129P2-Apoetm3(APOE*4)Mae N8, Taconic Transgenic ModelsM-bM-^DM-", http://www.taconic.com/wmspage.cfm?parm1=2542), purchased at the age of 6-8 weeks, strain C57BL/6, 3 months old at the performance of the microarray, 6 weeks on a high-fat diet containing 41% energy from milk fat and 2 g/kg cholesterol.
Project description:Gene expression profiles generated from human tumor cells laser-microdissected from surgical samples of seven choroid plexus papillomas (Grade I WHO) as eight samples of epithelial cells lasermicrodissected from normal choroid plexus obtained at autopsy. Choroid plexus tumors are rare pediatric brain tumors derrived from the choroid plexus epithelium. Gene expression profiles of lasermicrodissected tumor cells from 7 individual choroid plexus tumor samples obtained at surgery were compared to gene expression profiles from non-neoplastic choroid plexus epithelial cells lasermicrodissected from normal non-neoplastic choroid plexus obtained at autopsy (Am J Surg Pathol. 2006 Jan;30(1):66-74.) in order to identfy genes differentially expressed in choroid plexus tumor cells.