TY - JOUR A1 - Böhm, Lena A1 - Torsin, Sanda A1 - Tint, Su Hlaing A1 - Eckstein, Marie Therese A1 - Ludwig, Tobias A1 - Pérez, J. Christian T1 - The yeast form of the fungus Candida albicans promotes persistence in the gut of gnotobiotic mice JF - PLoS Pathogens N2 - Many microorganisms that cause systemic, life-threatening infections in humans reside as harmless commensals in our digestive tract. Yet little is known about the biology of these microbes in the gut. Here, we visualize the interface between the human commensal and pathogenic fungus Candida albicans and the intestine of mice, a surrogate host. Because the indigenous mouse microbiota restricts C. albicans settlement, we compared the patterns of colonization in the gut of germ free and antibiotic-treated conventionally raised mice. In contrast to the heterogeneous morphologies found in the latter, we establish that in germ free animals the fungus almost uniformly adopts the yeast cell form, a proxy of its commensal state. By screening a collection of C. albicans transcription regulator deletion mutants in gnotobiotic mice, we identify several genes previously unknown to contribute to in vivo fitness. We investigate three of these regulators—ZCF8, ZFU2 and TRY4—and show that indeed they favor the yeast form over other morphologies. Consistent with this finding, we demonstrate that genetically inducing non-yeast cell morphologies is detrimental to the fitness of C. albicans in the gut. Furthermore, the identified regulators promote adherence of the fungus to a surface covered with mucin and to mucus-producing intestinal epithelial cells. In agreement with this result, histology sections indicate that C. albicans dwells in the murine gut in close proximity to the mucus layer. Thus, our findings reveal a set of regulators that endows C. albicans with the ability to endure in the intestine through multiple mechanisms. KW - Candida albicans KW - deletion mutagenesis KW - gastrointestinal tract KW - fungi KW - regulator genes KW - gene regulation KW - mouse models KW - fungal genetics Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159120 VL - 13 IS - 10 ER - TY - JOUR A1 - Klein-Hessling, Stefan A1 - Muhammad, Khalid A1 - Klein, Matthias A1 - Pusch, Tobias A1 - Rudolf, Ronald A1 - Flöter, Jessica A1 - Qureischi, Musga A1 - Beilhack, Andreas A1 - Vaeth, Martin A1 - Kummerow, Carsten A1 - Backes, Christian A1 - Schoppmeyer, Rouven A1 - Hahn, Ulrike A1 - Hoth, Markus A1 - Bopp, Tobias A1 - Berberich-Siebelt, Friederike A1 - Patra, Amiya A1 - Avots, Andris A1 - Müller, Nora A1 - Schulze, Almut A1 - Serfling, Edgar T1 - NFATc1 controls the cytotoxicity of CD8\(^{+}\) T cells JF - Nature Communications N2 - Cytotoxic T lymphocytes are effector CD8\(^{+}\) T cells that eradicate infected and malignant cells. Here we show that the transcription factor NFATc1 controls the cytotoxicity of mouse cytotoxic T lymphocytes. Activation of Nfatc1\(^{-/-}\) cytotoxic T lymphocytes showed a defective cytoskeleton organization and recruitment of cytosolic organelles to immunological synapses. These cells have reduced cytotoxicity against tumor cells, and mice with NFATc1-deficient T cells are defective in controlling Listeria infection. Transcriptome analysis shows diminished RNA levels of numerous genes in Nfatc1\(^{-/-}\) CD8\(^{+}\) T cells, including Tbx21, Gzmb and genes encoding cytokines and chemokines, and genes controlling glycolysis. Nfatc1\(^{-/-}\), but not Nfatc2\(^{-/-}\) CD8\(^{+}\) T cells have an impaired metabolic switch to glycolysis, which can be restored by IL-2. Genome-wide ChIP-seq shows that NFATc1 binds many genes that control cytotoxic T lymphocyte activity. Together these data indicate that NFATc1 is an important regulator of cytotoxic T lymphocyte effector functions. KW - cytotoxic T cells KW - lymphocyte activation KW - signal transduction KW - gene regulation KW - immune cells KW - NFATc1 Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170353 VL - 8 IS - 511 ER -