Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Effect of microgravity on brain gene expression in mice

ABSTRACT: Changes in gravitational force such as that experienced by astronauts during space flight induce a redistribution of fluids from the caudad to the cephalad portion of the body together with an elimination of normal head-to-foot hydrostatic pressure gradients. To assess brain gene profile changes associated with microgravity and fluid shift, a large-scale analysis of mRNA expression levels was performed in the brains of 2 weeks control and hindlimb-unloaded (HU) mice using cDNA microarrays. Although to different extent, all functional categories displayed significantly regulated genes indicating that considerable transcriptomic alterations are induced by HU. Interestingly, the TIC class (transport of small molecules and ions into the cells) had the highest percentage of up-regulated genes, while the most down-regulated genes were those of the JAE class (Cell junction, Adhesion, Extracellular Matrix). TIC genes comprised 16% of those whose expression was altered, including sodium channel, nonvoltage-gated 1 beta (Scnn1b), glutamate receptor (Grin1), voltage-dependent anion channel 1 (Vdac1), calcium channel beta 3 subunit (Cacnb3) and others. The analysis performed by GeneMAPP revealed several altered protein classes and functional pathways such as blood coagulation and immune response, learning and memory, ion channels and cell junction. In particular, data indicate that HU causes an alteration in hemostasis which resolves in a shift toward a more hyper-coagulative state with an increased risk of venous thrombosis. Furthermore, HU treatment seems to impact on key steps of synaptic plasticity and learning processes. We used brains of four control (C1, C2, C3, C4) and four tail-suspended hindlimb-unloaded (E1, E2, E3, E4) mice to ensure statistical relevance of the study. 60 ug of total RNA extracted in TRIzol from each brain was reversed transcribed into labeled cDNAs using fluorescent Cy5 or Cy3-dUTP (Amersham Biosciences, NJ). Differently labeled cDNAs obtained from a pair of biological replicas were co-hybridized overnight at 50C with a microscope slide spotted with ~ 27,000 mouse cDNA sequences produced by the Microarray Core Facility of the Albert Einstein College of Medicine in the “multiple yellow” design (i.e.: C1C2, C3C4, E1E2, E3E4), described in Iacobas DA, Fan C, Iacobas S et al., Transcriptomic changes in developing kidney exposed to chronic hypoxia. Biochem Biophys Res Commun. 2006 349(1):329-38).

ORGANISM(S): Mus musculus

SUBMITTER: Dumitru Iacobas

PROVIDER: E-GEOD-12312 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Publications

Effect of microgravity on gene expression in mouse brain.

Frigeri Antonio A Iacobas Dumitru A DA Iacobas Sanda S Nicchia Grazia Paola GP Desaphy Jean Francois JF Camerino Diana Conte DC Svelto Maria M Spray David C DC

Experimental brain research 20080814 3

Changes in gravitational force such as that experienced by astronauts during space flight induce a redistribution of fluids from the caudad to the cephalad portion of the body together with an elimination of normal head-to-foot hydrostatic pressure gradients. To assess brain gene profile changes associated with microgravity and fluid shift, a large-scale analysis of mRNA expression levels was performed in the brains of 2-week control and hindlimb-unloaded (HU) mice using cDNA microarrays. Althou ...[more]

PMID: 18704384

Similar Datasets

Project description:Microarray experiments have generally focused on magnitude of gene expression changes in pathological conditions, thereby using the method as a high throughput screen to identify candidate marker genes and/or to validate phenotypic differences. We have used novel strategies to extract additional information from array studies, including expression variability and coordination, from which organizational principles of transcriptomes are emerging. We have reported that expression level, variability and coordination of numerous genes are regulated in brains of Gja1-/- mice with respect to wildtypes. Moreover, expression coordination with Gja1 in wildtypes largely predicted expression regulation in Gja1-/- tissues. We now report a remarkable overlap between regulations in Gja1-/- and Gjb1-/- brains, and that both differ markedly from those in Gja9-/- brain. Since in brain these three connexins are expressed in different cell types (Gja1 in astrocytes, and ependymal and vascular cells, Gjb1 in oligodendrocytes, and Gja9 in neurons and microglia), and because astrocytes and oligodendrocytes may form syncytia coupled by gap junction channels, these observations suggest the existence of distinct connexin-dependent panglial and neuronal transcriptomic networks. Such networks, where linkage partners are rearranged and strengths modified in brains of knockouts, may explain downstream and parallel 'ripples' of phenotypic change resulting from single gene alterations as the composition and interactions of transcription factor networks in the wildtype brain were identified and found to be altered disruption of Gja1 or Gjb1. The transcription factors also formed network hubs with genes from other functional categories, thus allowing regulation of one functional pathway through manipulation of another. Keywords: genetic modification The brain transcriptomes of Gja9(-/-) and Gja9(+/-) P10 mice were compared to that of P10 wildtype mouse using the "multiple yellow" design in which extracts of biological replicas of the same genotype were hybridized with six 27k AECOM mouse cDNA microarrays (4 biological replicas of each genotype). These data were further compared to previously reported data on brain of neonatal wildtype, Gja1(-/-), Gja1(+/-) and Gjb1(-/-) mice (four biological replicas per genotype, reference sample design).

Project description:One way by which astrocytes modulate oligodendrocytes’ activity is by delivering neurotransmitters and leukemia inhibitory factor (Lif) in the medium that bind oligodendrocyte receptors. Most of these receptors are involved in intercellular Ca2+-signaling (ICS). However, not much is known about the interactions between myelination (MYE) and ICS genes and how astrocyte nearness modulates the oligodendrocyte genomic myelination fabric. We profiled the transcriptomes of immortalized oligodendrocyte precursor cells (Oli-neu) when cultured alone or co-cultured with cortical astrocytes. The astrocytes were plated in cell culture insert systems that did not allow formation of gap junction channels with oligodendrocytes but permitted exchange of soluble factors via the culture medium. Remarkably, astrocyte proximity induced a larger increase of the overall expression level and interlinkage of MYE genes than the differentiating 10d treatment with 1 mM dibutyryl cAMP that turns Oli-neu cells into myelin-associated glycoprotein-positive oligodendrocyte-like cells. Moreover, more MYE and ICS genes were turned on and fewer turned off by astrocyte proximity than by differentiating treatment. Lif receptor was up-regulated by astrocyte proximity but not by the differentiating treatment. We have identified the responsible transcriptomic networks by which the intercellular ICS gene web controls MYE gene web, with genes encoding the gap junction proteins (connexins, Cx) Cx29, Cx32 and Cx47 playing central roles. The novel Prominent Gene Analysis (that refines iteratively the functional webs to optimize the interconnectivity and expression stability of the associated genes) was used to select and rank the most relevant MYE and ICS genes and build the corresponding gene webs. Determine the modifications of the myelination transcriptome induced in Oli- neu control cells by differentiating treatment and proximity of cortical astrocytes. Four culture dishes of each of control, differentiated and in the astrocyte proximity Oli-neu cells were profiled using Duke mouse 30K and 36k oligonucleotide arrays in the "multiple yellow" hybrization design.

Project description:Expression level, control and intercoordination of 66 selected heart rhythm determinant (HRD) genes were compared in atria and ventricles of 4 male and 4 female adult mice. We found that genes encoding various adrenergic receptors, ankyrins, ion channels and transporters, connexins and other components of the intercalated discs form a complex network that is chamber dependent and differs between the two sexes. In addition, most HRD genes in atria had higher expression in males than in females, while in ventricles expression levels were mostly higher in females than in males. Moreover, significant chamber-differences were observed between the sexes, with higher expression in atria than ventricles for males and higher expression in ventricles than atria for females. We have ranked the selected genes according to their prominence in controlling the HRD gene web through expression coordination with the other web genes and protecting the web though their own expression stability. Interestingly, the prominence hierarchy was substantially different between the two sexes. Taken together these findings indicate that the organizational principles of the heart rhythm transcriptome are sex-dependent, with the newly introduced prominence analysis allowing identification of genes that are pivotal for the sexual dichotomy. Four adult male (M) and 4 adult female (F) mice were decapitated, the hearts removed and atria (A) and ventricles (V) collected in separate tubes. 20 Âµg total RNA extracted in Trizol from each of the 16 samples was reverse transcribed in the presence of fluorescent Alexa FluorÂ®_647 and Alexa FluorÂ®_555-aha-dUTPs (Invitrogen, CA) to obtain labeled cDNAs Red and green-labeled samples of biological replicas were then co-hybridized (âmultiple yellowâ strategy) overnight at 50Â°C with mouse MO36k oligonucleotide arrays printed by Duke University (http://microarray.genome.duke.edu/spotted-arrays) with Operon Mouse Oligo Set, version 4.0. After washing (0.1% SDS and 1% SSC) to remove the non-hybridized cDNA, each array was scanned with GenePix 4000B scanner (MDS, Toronto, Canada) and images were primarily analyzed with GenePixPro 6.0 (Axon Instruments, CA).

Project description:Injury of the CA1 subregion induced by a single injection of kainic acid (1M-CM-^WKA) is attenuated when juvenile animals (P20) have a history of two sustained neonatal seizures on P6 and P9. To identify gene candidates involved in the spatially protective effects produced by early life conditioning seizures, we profiled and compared the transcriptomes of CA1 subregions from control, 1M-CM-^WKA, and 3M-CM-^WKA treated animals. More genes were regulated following 3M-CM-^WKA (9.6%) than after 1M-CM-^WKA (7.1%). Following 1M-CM-^WKA, genes supporting oxidative stress, growth, development, inflammation, and neurotransmission were upregulated (e.g., Cacng1, Nadsyn1, Kcng1, Aven, S100a4, GFAP, Vim, Hrsp12, Grik1). After 3M-CM-^WKA, protective genes were differentially over-expressed (e.g., Cat, Gpx7, GAD1, Hspa12A, Foxn1, adenosine A1 receptor, Ca2+ adaptor and homeostatic proteins, Cacnb4, Atp2b2, anti-apoptotic Bcl-2 gene members, intracellular trafficking protein, Grasp, suppressor of cytokine signaling (Socs3)). Distinct anti-inflammatory interleukins not observed in adult tissues (e.g., IL6 transducer, IL23 and IL33 or their receptors (ILF2)) were also over-expressed. Several transcripts were validated by real-time polymerase chain reaction (QPCR) and immunohistochemistry. QPCR showed that casp 6 was increased after 1M-CM-^WKA but reduced after 3M-CM-^WKA; pro-inflammatory gene cox1 was either upregulated or unchanged after 1M-CM-^WKA but reduced by ~70% after 3M-CM-^WKA. Enhanced GFAP immunostaining following 1M-CM-^WKA was selectively attenuated in the CA1 subregion after 3M-CM-^WKA. The observed differential transcriptional responses may contribute to early life seizure-induced pre-conditioning and neuroprotection by reducing glutamate receptor-mediated Ca2+ permeability of the hippocampus and redirecting inflammatory and apoptotic pathways which could lead to new genetic therapies for epilepsy. The transcriptomes of the hippocampal CA1 region of Sprague Dawley 23-day-old male rats after 1 or 3 seizures induced by kainic acid injection were compared to the corresponding controls (injected with PBS) using Duke 27k oligonucleotide arrays.

Dataset Information

Effect of microgravity on brain gene expression in mice

Publications

Effect of microgravity on gene expression in mouse brain.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets