The transcription factor STAT1 is essential for interferon- (IFN) mediated protective immunity in humans and mice. Two splice isoforms of STAT1, STAT1 and STAT1, differ with regard to a C-terminal transactivation domain, which is absent in STAT1. Dimers of STAT1 are therefore considered transcriptionally inactive and potential competitive inhibitors of STAT1. Contrasting this view, generation and analysis of mice deficient for either STAT1 or STAT1 demonstrated transcriptional activity of the STAT1 isoform and its enhancement of innate immunity. Gene expression profiling in primary cells revealed overlapping, but also non-redundant and gene-specific activities of STAT1 and STAT1 in response to IFN. Consistently, both isoforms mediated protective, IFN-dependent immunity against the bacterium Listeria monocytogenes, although with remarkably different efficiency. In contrast, STAT1 and STAT1 were largely redundant for transcriptional responses to IFN/ and for IFN/-dependent antiviral activity. Collectively, our data shed new light on how STAT1 isoforms contribute to antimicrobial immunity.
STAT1β is not dominant negative and is capable of contributing to gamma interferon-dependent innate immunity.
Specimen part
View SamplesThis research focus primarily on the interaction between influenza virus and endothelial cell, then we used microarrays to observe global patterns of gene expression in Human Umbilical Vein Endothelial Cells after influenza virus infection and offer further insight into the interaction between endothelial cells and influenza viruses.
No associated publication
Specimen part
View SamplesToxoplasma infection can cause damage to the male reproductive system, such as sexual dysfunction and infertility. The epididymis is an important accessory organ of male reproductive system, where sperm maturation and storage take place. Sperm maturation in the epididymis is a highly programmed process, which may be affected by the epididymis microenvironment. Therefore, studying the epididymis characteristics is important for identification of factors affecting sperm maturation. However, studies investigating the differential expression genes of host and Toxoplasma gondii by transcriptome sequencing of the male reproductive system are limited. The main objective of this study was to examine differential gene expression by RNA sequencing (RNA-seq) technology in order to identify key genes associated with Toxoplasma gondii (PRU strain) chronic infection of the epididymis in male Kunming mice.
No associated publication
Sex, Age, Specimen part, Cell line
View SamplesThe bursa of Fabricius is an immune organ unique to birds and possesses a specialized micro-environment that supports the differentiation of B cells and production of antibodies but, it can be damaged by lipopolysaccharide (LPS) derived from Salmonella typhimurium, one of the most deleterious food-borne pathogens. However, its mechanism of action at transcriptional level is poorly known yet. Therefore, the current project was designed and bursa of Fabricius from newly hatched chicks were sequenced at 12, 36 and 72 hours post saline and LPS treatments with 3 replications at each time point.
No associated publication
Sex, Specimen part, Disease stage, Treatment
View SamplesComparative analysis of gene expression profiles in newly developed housing systems is important to understand gene functions in chicken for adaptation and possible gene-environment interactions among layer lines. Therefore, the objective of this study was to characterize the molecular processes that are different among the two layer lines Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) using whole genome RNA expression profiles. Despite their approximately identical egg production performance these layer lines differ markedly in other phenotypic traits. The two layer lines were kept under the production environment of the newly developed small group housing system Eurovent German with two different group sizes and three tiers.
Differential gene expression from genome-wide microarray analyses distinguishes Lohmann Selected Leghorn and Lohmann Brown layers.
Specimen part
View SamplesDuplication of eukaryotic genomes during S phase is coordinated in space and time. In order to identify zones of initiation and cell-type as well as gender-specific plasticity of DNA replication, we profiled replication timing, histone acetylation and transcription throughout the Drosophila genome. We observed two waves of replication initiation with many distinct zones firing in early and multiple, less defined peaks at the end of S phase, suggesting that initiation becomes more promiscuous at the end of S phase. A comparison of different cell types revealed widespread plasticity of replication timing on autosomes. Most occur in large regions but only half coincide with local differences in transcription. In contrast to confined autosomal differences, a global shift in replication timing occurs throughout the single male X chromosome. Unlike in females, the dosage compensated X chromosome replicates almost exclusively early. This difference occurs at sites which are not transcriptionally hyperactivated, but show increased acetylation of lysine 16 of histone H4. This suggests a transcription-independent, yet chromosome-wide process related to chromatin. Importantly, H4K16ac is also enriched at initiation zones as well as early replicating regions on autosomes during S phase. Together, our data reveal novel organizational principles of DNA replication of the Drosophila genome and imply chromatin structure as a determinant of replication timing locally and chromosome-wide.
Chromatin state marks cell-type- and gender-specific replication of the Drosophila genome.
Sex
View SamplesThe replication of a genomic region during S-phase can be highly dynamic between cell types that differ in transcriptome and epigenome. Replication timing has been positively correlated with several histone modifications that occur at active genes, while repressive histone modifications mark late replicating regions. This raises the question if chromatin modulates the initiating events of replication. To gain insights into this question we have studied the function of heterochromatin protein 1 (HP1), a reader of to the repressive histone lysine 9 methylation of H3, in genome-wide organization of replication. Cells with reduced levels of HP1 show an advanced replication timing of centromeric repeats in agreement with the model that repressive chromatin mediates the very late replication of large clusters of constitutive heterochromatin. Surprisingly however regions with high levels of interspersed repeats on the chromosomal arms in particular on chromosome 4 and in pericentromeric regions of chromosome 2 behave differently. Here loss of HP1 results in delayed replication timing. The fact that these regions are bound by HP1 suggests a direct effect. Thus while HP1 mediates very late replication of centromeric DNA it is also required for early replication of autosomal regions with high levels of repeats. This observation of opposing functions of HP1 suggests a model where repeat inactivation on autosomes is required for proper activation of origins of replication that fire early, while HP1 mediated repression at constitutive heterochromatin is required to ensure replication of centromeric repeats at the end of S phase.
Heterochromatin protein 1 (HP1) modulates replication timing of the Drosophila genome.
Sex, Specimen part
View SamplesThe benefit of treatment in mild to moderate cases of E. coli mastitis in dairy cows remains a topic of discussion.
Impact of intramammary treatment on gene expression profiles in bovine Escherichia coli mastitis.
Treatment, Time
View SamplesInsight into mechanisms controlling gene expression in the spermatogonial stem cell (SSC) will improve our understanding of the processes regulating spermatogenesis and aid in treating problems associated with male infertility.
Spermatogonial stem cell self-renewal requires ETV5-mediated downstream activation of Brachyury in mice.
Specimen part, Treatment
View SamplesFull title: Prepubertal Human Spermatogonia and Mouse Gonocytes Share Conserved Gene Expression of Germline Stem Cell Regulatory Molecules
Prepubertal human spermatogonia and mouse gonocytes share conserved gene expression of germline stem cell regulatory molecules.
Age
View Samples