Genomewide production of multipurpose alleles for the functional analysis of the mouse genome.

Department of Molecular Hematology, University of Frankfurt Medical School, 60590 Frankfurt am Main, Germany.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 06/2005; 102(20):7221-6. DOI: 10.1073/pnas.0502273102
Source: PubMed

ABSTRACT A type of retroviral gene trap vectors has been developed that can induce conditional mutations in most genes expressed in mouse embryonic stem (ES) cells. The vectors rely on directional site-specific recombination systems that can repair and re-induce gene trap mutations when activated in succession. After the gene traps are inserted into the mouse genome, genetic mutations can be produced at a particular time and place in somatic cells. In addition to their conditional features, the vectors create multipurpose alleles amenable to a wide range of post-insertional modifications. Here we have used these directional recombination vectors to assemble the largest library of ES cell lines with conditional mutations in single genes yet assembled, presently totaling 1,000 unique genes. The trapped ES cell lines, which can be ordered from the German Gene Trap Consortium, are freely available to the scientific community.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Conditional gene deletion in mice has contributed immensely to our understanding of many biological and biomedical processes. Despite an increasing awareness of nonprotein-coding functional elements within protein-coding transcripts, current gene-targeting approaches typically involve simultaneous ablation of noncoding elements within targeted protein-coding genes. The potential for protein-coding genes to have additional noncoding functions necessitates the development of novel genetic tools capable of precisely interrogating individual functional elements. We present a strategy that couples Cre/loxP-mediated conditional gene disruption with faithful GFP reporter expression in mice in which Cre-mediated stable inversion of a splice acceptor-GFP-splice donor cassette concurrently disrupts protein production and creates a GFP fusion product. Importantly, cassette inversion maintains physiologic transcript structure, thereby ensuring proper microRNA-mediated regulation of the GFP reporter, as well as maintaining expression of nonprotein-coding elements. To test this potentially generalizable strategy, we generated and analyzed mice with this conditional knockin reporter targeted to the Hmga2 locus.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mutations in RAB18 have been shown to cause the heterogeneous autosomal recessive disorder Warburg Micro syndrome (WARBM). Patients with WARBM present with a range of clinical symptoms including ocular and neurological abnormalities. However, the underlying cellular and molecular pathogenesis of the disorder remains unclear, largely due to the lack of any robust animal models phenocopying both ocular and neurological features of the disease. We report here the generation and characterisation of a novel Rab18 mutant mouse model of WARBM. Rab18 mutant mice are viable and fertile. They present with congenital nuclear cataracts and atonic pupils, recapitulating characteristic ocular features associated with WARBM. In addition, Rab18 mutant cells have an increase in lipid droplet size following treatment with oleic acid. Lipid droplet abnormalities are a characteristic feature of WARBM patient cells, as well as cells from patients with other neurodegenerative conditions. Neurological dysfunction is also apparent in Rab18 mutant mice, including progressive weakness of the hind limbs. We show that the neurological defects are most likely not due to gross perturbations in synaptic vesicle recycling in the central or peripheral nervous system. Rather, loss of Rab18 is associated with widespread disruption of the neuronal cytoskeleton, including abnormal accumulations of neurofilament and microtubule proteins in synaptic terminals and gross disorganisation of the cytoskeleton in peripheral nerves. Global proteomic profiling of peripheral nerve in Rab18 mutant mice reveals significant alterations in several core molecular pathways regulating cytoskeletal dynamics in neurons. The clear similarities between WARBM and the phenotype we describe indicate that the Rab18 mutant mouse provides an important platform for investigating the disease pathogenesis and therapeutic interventions.
    Disease Models and Mechanisms 04/2014; DOI:10.1242/dmm.015222 · 5.54 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The dynamic architecture of chromatin is vital for proper cellular function, and is maintained by the concerted action of numerous nuclear proteins, including that of the linker histone H1 variants, the most abundant family of nucleosome-binding proteins. Here we show that the nuclear protein HP1BP3 is widely expressed in most vertebrate tissues and is evolutionarily and structurally related to the H1 family. HP1BP3 contains three globular domains and a highly positively charged C-terminal domain, resembling similar domains in H1. Fluorescence recovery after photobleaching (FRAP) studies indicate that like H1, binding of HP1BP3 to chromatin depends on both its C and N terminal regions and is affected by the cell cycle and post translational modifications. HP1BP3 contains functional motifs not found in H1 histones, including an acidic stretch and a consensus HP1-binding motif. Transcriptional profiling of HeLa cells lacking HP1BP3 showed altered expression of 383 genes, suggesting a role for HP1BP3 in modulation of gene expression. Significantly, Hp1bp3(-/-) mice present a dramatic phenotype with 60% of pups dying within 24 h of birth and the surviving animals exhibiting a lifelong 20% growth retardation. We suggest that HP1BP3 is a ubiquitous histone H1 like nuclear protein with distinct and non-redundant functions necessary for survival and growth. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.
    Nucleic Acids Research 02/2015; 43(4). DOI:10.1093/nar/gkv089 · 8.81 Impact Factor

Full-text (2 Sources)

Available from
May 21, 2014