Project description:In chicks, the avian homologue of the early growth response protein-1 (ZENK) has been shown to be increased in a special cell type of the retina, the glucagonergic amacrine cells, under conditions that lead to a reduction in eye growth (myopic defocus, recovery of myopia) and decreased under conditions that enhance ocular growth (hyperopic defocus, form-deprivation). The investigation of Egr-1 knock-out mice showed that homozygous knock-out mice with no functional Egr-1 protein developed relative axial myopia at the age of 42 and 56 days, compared to heterozygous- and wildtype Egr-1 knock-out mice. To clarify the role of Egr-1 in the retinal regulation of eye growth, and to get an idea about the biochemical pathways underlying this mechanism, we studied the role of Egr-1 in more detail using Affymetrix microarrays. Experiment Overall Design: Retinal samples of young homozygous Egr-1 knock-out and wildtype mice at the age of 30 days (hm30 and wt30; no difference in axial eye length yet) and 42 days (hm42 and wt42; already a difference in axial eye length of 59 µm) were taken to compare the mRNA expression changes over time between these two genotypes and within the same genotype between the two age groups.
Project description:In chicks, the avian homologue of the early growth response protein-1 (ZENK) has been shown to be increased in a special cell type of the retina, the glucagonergic amacrine cells, under conditions that lead to a reduction in eye growth (myopic defocus, recovery of myopia) and decreased under conditions that enhance ocular growth (hyperopic defocus, form-deprivation). The investigation of Egr-1 knock-out mice showed that homozygous knock-out mice with no functional Egr-1 protein developed relative axial myopia at the age of 42 and 56 days, compared to heterozygous- and wildtype Egr-1 knock-out mice. To clarify the role of Egr-1 in the retinal regulation of eye growth, and to get an idea about the biochemical pathways underlying this mechanism, we studied the role of Egr-1 in more detail using Affymetrix microarrays.
Project description:To investigate the functional importance of a nucleoside transporter, the mENT1 (Slc29a1) was knocked out in mice. The gene expression profile was compared between wildtype and mENT1 knock out mice in two tissues.
Project description:The guanine-rich RNA sequence binding factor 1 (GRSF1) is an RNA-binding protein of the heterogenous nuclear ribonucleoprotein H/F (hnRNP H/F) family that binds to guanine-rich RNA sequences forming G-quadruplex structures. In mice and humans there are single copy GRSF1 genes, but multiple transcripts have been reported. The RNA-binding protein GRSF1 has been implicated in a number of physiological processes (e.g. embryogenesis, erythropoiesis, redox homeostasis, RNA metabolism) but also in the pathogenesis of viral infections and hyperproliferative diseases. These postulated biological functions of GRSF1 originates from in vitro studies rather than complex in vivo systems. To assess the in vivo relevance of these findings, we created systemic Grsf1-/- knockout mice lacking exons 4 and 5 of the Grsf1 gene and compared the basic functional characteristics of these animals with those of wildtype controls. We found that Grsf1-deficient mice are viable, reproduce normally and have fully functional hematopoietic systems. Up to an age of 15 weeks they develop normally but when male individuals grow older, they gain significantly less body weight than wildtype controls in a gender specific way. Profiling Grsf1 mRNA expression in different mouse tissues we observed high concentrations in testis. Comparison of the testicular transcriptomes of Grsf1-/- mice and wildtype controls confirmed near complete knock-out of Grsf1 but otherwise subtle differences in transcript regulations. Comparative testicular proteome analyses suggested perturbed mitochondrial respiration in Grsf1-/- mice which may be related to compromised expression of complex I proteins. Here we present, for the first time, an in vivo complete Grsf1 knock-out mouse with comprehensive physiological, transcriptomic and proteomic characterization to improve our understanding of the GRSF1 beyond in vitro cell culture models.
Project description:To investigate the functional importance of a nucleoside transporter, the mENT1 (Slc29a1) was knocked out in mice. The gene expression profile was compared between wildtype and mENT1 knock out mice in two tissues. RNA was isolated from heart and kidney from 3 mENT1 knockout and 3 wildtype (FVB/N) mice.Gene expression profiles were compared between the knockout and wild type tissues.
Project description:Mutant JAK2V617F is found in majority of patients with myeloproliferative neoplasm. While heterozygous JAK2V617F induced an ET-like phenotype, JAK2V617F homozygosity drives an severe PV-like phenotype in knock-in mice. HSCs from mice with homozygous JAK2V617F expression show impaired self-renewal in transplants. To understand the molecular mechanisms involved this HSC functional defect, microarray was performed on isolated LT-HSCs from mice expressing wildtype, heterozygous and homozygous expression of mutant JAK2.
Project description:au-09-01_mpk_flagellin_edu - bak1bkk1 - Investigate flagellin mpk dependent genes by comparision between bak1bkk1 and col-0. Keywords: gene knock out
Project description:Malat1 is an abundant long noncoding RNA that localizes to nuclear bodies known as nuclear speckles, which contain a distinct set of pre-mRNA processing factors. Previous in vitro studies have demonstrated that Malat1 interacts with pre-mRNA splicing factors, including the serine- and arginine-rich (SR) family of proteins, and regulates a variety of biological processes, including cancer cell migration, synapse formation, cell cycle progression, and responses to serum stimulation. To address the physiological function of Malat1 in a living organism, we generated Malat1-KO (KO) mice using homologous recombination. Unexpectedly, the Malat1-KO mice were viable and fertile, showing no apparent phenotypes. Nuclear speckle markers were also correctly localized in cells that lacked Malat1. However, the cellular levels of another long noncoding RNA, Neat1, which is an architectural component of nuclear bodies known as paraspeckles, were downregulated in a particular set of tissues and cells lacking Malat1. To address if the absence of Malat1 affects the expression of other genes, including other long noncoding RNA, microarrays were used to study the impact of knocking-out Malat1 on global gene expression in hippocampal neurons. Hippocampi were dissected from two sets of wildtype and Malat1 knock-out mice and RNA from these neurons were hybridized to Affymetix mouse exon array. Individual animals from each pairs of wildtype and knock-out are littermates.