10. These authors contributed equally to the work.11. These authors contributed equally to the work. AbstractThe metazoan hypoxic response is regulated by the oxygen-dependent posttranslational hydroxylation of the -subunits of the hypoxia inducible factor (HIF)system. This identification has raised the question of whether other proteinhydroxylases are involved in the regulation of gene expression. Here we demonstrate that the splicing factor protein U2AF65 undergoes post-translational lysyl-5-hydroxylation as catalysed by the Fe(II) and 2-oxoglutarate dependent dioxygenaseJumonji domain-containing protein 6 (Jmjd6). Jmjd6 is a nuclear protein that has an important role in vertebrate development and is a close human homologue of the hypoxia inducible factor asparaginyl-hydroxylase. Jmjd6 is shown to regulate alternative RNA splicing of endogenous and reporter genes. The ability of Jmjd6 to influence the splicing pattern of all endogenous genes investigated supports a specific role for Jmjd6 in regulating RNA splicing. Main textMetazoan cells respond to limiting oxygen by activation of the hypoxia inducible factor (HIF) system(1). The HIF subunits are regulated by Fe(II) and 2-oxoglutarate

BackgroundThe mouse inbred line C57BL/6J is widely used in mouse genetics and its genome has been incorporated into many genetic reference populations. More recently large initiatives such as the International Knockout Mouse Consortium (IKMC) are using the C57BL/6N mouse strain to generate null alleles for all mouse genes. Hence both strains are now widely used in mouse genetics studies. Here we perform a comprehensive genomic and phenotypic analysis of the two strains to identify differences that may influence their underlying genetic mechanisms.ResultsWe undertake genome sequence comparisons of C57BL/6J and C57BL/6N to identify SNPs, indels and structural variants, with a focus on identifying all coding variants. We annotate 34 SNPs and 2 indels that distinguish C57BL/6J and C57BL/6N coding sequences, as well as 15 structural variants that overlap a gene. In parallel we assess the comparative phenotypes of the two inbred lines utilizing the EMPReSSslim phenotyping pipeline, a broad based assessment encompassing diverse biological systems. We perform additional secondary phenotyping assessments to explore other phenotype domains and to elaborate phenotype differences identified in the primary assessment. We uncover significant phenotypic differences between the two lines, replicated across multiple centers, in a number of physiological, biochemical and behavioral systems.ConclusionsComparison of C57BL/6J and C57BL/6N demonstrates a range of phenotypic differences that have the potential to impact upon penetrance and expressivity of mutational effects in these strains. Moreover, the sequence variants we identify provide a set of candidate genes for the phenotypic differences observed between the two strains.

In causing disease, pathogens outmaneuver host defenses through a dedicated arsenal of virulence determinants that specifically bind or modify individual host molecules. This dedication limits the intruder to a defined range of hosts. Newly emerging diseases mostly involve existing pathogens whose arsenal has been altered to allow them to infect previously inaccessible hosts. We have emulated this chance occurrence by extending the host range accessible to the human pathogen Listeria monocytogenes by the intestinal route to include the mouse. Analyzing the recognition complex of the listerial invasion protein InlA and its human receptor E-cadherin, we postulated and verified amino acid substitutions in InlA to increase its affinity for E-cadherin. Two single substitutions increase binding affinity by four orders of magnitude and extend binding specificity to include formerly incompatible murine E-cadherin. By rationally adapting a single protein, we thus create a versatile murine model of human listeriosis.

Vacuolar-vesicular protein sorting (Vps) factors are involved in vesicular trafficking in eukaryotic cells. We identified the missense mutation L967Q in Vps54 in the wobbler mouse, an animal model of amyotrophic lateral sclerosis, and also characterized a lethal allele, Vps54(beta-geo). Motoneuron survival and spermiogenesis are severely compromised in the wobbler mouse, indicating that Vps54 has an essential role in these processes.

IntroductionThe steroid hormone 1␣,25-dihydroxyvitamin D 3 (1␣,25(OH) 2 D 3 ) is known for its important role in regulating calcium homeostasis and bone mineralization. 1 1␣,25(OH) 2 D 3 acts through a nuclear receptor, the vitamin D receptor (Vdr), which is a member of the steroid and thyroid hormone receptor superfamily. More recently, evidence has accumulated that the hormone can have important functions in the immune system. Expression of Vdr was found in different immune effector cells of the myeloid and lymphoid lineage under resting and activating conditions. 2,3 These findings contributed to the hypothesis that locally produced 1␣,25(OH) 2 D 3 may perform regulatory functions on those cells. Indeed, over the past few years it has been demonstrated that 1␣,25(OH) 2 D 3 can act as an important immunosuppressive modulator. 1␣,25(OH) 2 D 3 has been shown to suppress T-cell proliferation 4 and to decrease the production of the T helper type 1 (Th1) cytokines interleukin 2, interferon ␥ (IFN-␥), and tumor necrosis factor ␣ (TNF-␣), leading to the inhibition of Th1 cell development. 5 Besides its direct effects on T cells, 1␣,25(OH) 2 D 3 and its analogs are potent inhibitors of dendritic cell (DC) differentiation and maturation and can impair the capacity of DCs to induce alloreactive T-cell activation. 6,7 In line with this, Vdr-deficient mice have been shown to have an increased frequency of mature DCs in lymph nodes. 8 Additional support for the immunomodulatory role of 1␣,25(OH) 2 D 3 in vivo came from studies of autoimmune diseases in several different animal models. It has been demonstrated that 1␣,25(OH) 2 D 3 can prevent or suppress experimental autoimmune encephalomyelitis, 9 rheumatoid arthritis, 10 systemic lupus erythematosus, 11 type 1 diabetes, 12 and inflammatory bowel disease, 13,14 further supporting its potent suppressive effects on the immune system.In contrast to its well-characterized effects on adaptive immune responses, much less is known about the effects of 1␣,25(OH) 2 D 3 on effectors of innate immunity, especially on macrophages. It has been shown that 1␣,25(OH) 2 D 3 can induce the differentiation of myeloid progenitors into macrophages. 15,16 However, the effects of 1␣,25(OH) 2 D 3 on mature and activated macrophages that are involved in inflammatory reactions have not been characterized yet. Such possible effects might be of especial importance since it was demonstrated that macrophages can release biologically active 1␣,25(OH) 2 D 3 on activation with IFN-␥. 17,18 The production of 1␣,25(OH) 2 D 3 by activated macrophages is regulated by the IFN-␥-mediated induction of 1␣-hydroxylase expression, the enzyme controlling the last step of 1␣,25(OH) 2 D 3 synthesis. 17,18 In Supported by the National German Genome Network (NGFN; 01GR0439), EU FP5 project EUMORPHIIA (QLG2- CT-2002-00930), and Volkswagenstiftung.L.H. performed research and wrote the paper; J.B., J.E., and S.S. performed research; T.F. contributed reagents and analytical tools; R.G. and M.P.K analyzed data; R.B. initiate...

Salmonella Typhimurium specifically targets antigen-sampling microfold (M) cells to translocate across the gut epithelium. Although M cells represent a small proportion of the specialized follicular-associated epithelium (FAE) overlying mucosa-associated lymphoid tissues, their density increases during Salmonella infection, but the underlying molecular mechanism remains unclear. Using in vitro and in vivo infection models, we demonstrate that the S. Typhimurium type III effector protein SopB induces an epithelial-mesenchymal transition (EMT) of FAE enterocytes into M cells. This cellular transdifferentiation is a result of SopB-dependent activation of Wnt/β-catenin signaling leading to induction of both receptor activator of NF-κB ligand (RANKL) and its receptor RANK. The autocrine activation of RelB-expressing FAE enterocytes by RANKL/RANK induces the EMT-regulating transcription factor Slug that marks epithelial transdifferentiation into M cells. Thus, via the activity of a single secreted effector, S. Typhimurium transforms primed epithelial cells into M cells to promote host colonization and invasion.

JmjC domain-containing proteins play a crucial role in the control of gene expression by acting as protein hydroxylases or demethylases, thereby controlling histone methylation or splicing. Here, we demonstrate that silencing of Jumonji domain-containing protein 6 (Jmjd6) impairs angiogenic functions of endothelial cells by changing the gene expression and modulating the splicing of the VEGF-receptor 1 (Flt1). Reduction of Jmjd6 expression altered splicing of Flt1 and increased the levels of the soluble form of Flt1, which binds to VEGF and placental growth factor (PlGF) and thereby inhibits angiogenesis. Saturating VEGF or PlGF or neutralizing antibodies directed against soluble Flt1 rescued the angiogenic defects induced by Jmjd6 silencing. Jmjd6 interacts with the splicing factors U2AF65 that binds to Flt1 mRNA. In conclusion, Jmjd6 regulates the splicing of Flt1, thereby controlling angiogenic sprouting.

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