Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A FOXN1 mutation competitively displaces wild-type FOXN1 from higher-order nuclear condensates to cause immunodeficiency

ABSTRACT: The transcription factor FOXN1 is a master regulator of thymic epithelial cell development and function. Here we demonstrate that FOXN1 expression is differentially regulated during organogenesis and participates in multi-molecular nuclear condensates essential for the factor's transcriptional activity. FOXN1's C-terminal sequence regulates the diffusion velocity within these aggregates and modulates the binding to proximal gene regulatory regions. These dynamics are significantly altered in a patient's FOXN1 mutant modified in its C-terminal sequence. This mutant is transcriptionally inactive and acts as a dominant negative factor displacing wild-type FOXN1 from condensates and causing athymia and severe lymphopenia in heterozygotes. Expression of the mutated mouse ortholog, Foxn1, selectively impairs mouse thymic epithelial cell (TEC) differentiation, revealing a gene dose dependency for individual TEC subtypes. We have therefore identified the cause for a primary immunodeficiency disease and determined the mechanism by which this FOXN1 gain-of-function mutant mediates its dominant negative effect.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Medullary Thymic Epithelial Cell, Cell Culture

SUBMITTER: Philip Charles

LAB HEAD: Georg Hollander

PROVIDER: PXD025552 | Pride | 2021-10-29

REPOSITORIES: Pride

ACCESS DATA

Json Xml

Similar Datasets

Disruption of higher order nuclear condensates by a dominant negative FOXN1 mutation causes immunodeficiency

Project description:The transcription factor FOXN1 acts in a gene-dosage sensitive way as a master regulator of thymic epithelial cell development and maintenance enabling effective thymopoiesis. Its autosomal recessive loss of function is the molecular cause of the “nude” phenotype, a severe combined immunodeficiency caused by athymia. Here we report on a spontaneously occurring, novel heterozygous FOXN1 mutation that initially permits regular thymus organogenesis but results in a failure of thymic maintenance beyond late stages of human gestation. Modeling the mutation in mice results in divergent disruptions of normal TEC subtype differentiation and function. Transcriptionally inactive, the mutant disrupts the formation of wild type FOXN1 homo-multimers and occupies canonical DNA binding sites, at which it operates in a dominant negative fashion to displace wild type FOXN1 from nuclear condensates. Comparing the interactome of the mutant and wild type FOXN1 identified binding partners that uniquely interact with wild type FOXN1 and are characteristic constituents of nuclear organelles required for transcription. Mutant FOXN1 moves in and out of condensates over a time-course indistinguishable from that of wild type FOXN1, suggesting that the mutation did not affect the molecular movement of FOXN1. Thus, we have identified a clinically relevant gain of function mutation of FOXN1 that actively prevents the transcriptional activity of wild type FOXN1 and provides critical insight into the mechanism by which FOXN1 operates in controlling sustained gene expression necessary for normal thymic epithelial cell differentiation, maintenance and function.

2021-10-12 | GSE162668 | GEO

microRNA expression in thymic epithelial cells

Project description:Thymic epithelial cells (TECs) support T cell development in the thymus. Cortical thymic epithelial cells (cTECs) facilitate positive selection of developing thymocytes whereas medullary thymic epithelial cells (mTECs) facilitate the deletion of self-reactive thymocytes in order to prevent autoimmunity. The mTEC compartment is highly dynamic with continuous maturation and turnover, but the genetic regulation of these processes remains poorly understood. MicroRNAs (miRNAs) are important regulators of TEC genetic programs since miRNA-deficient TECs are severely defective. However, the individual miRNAs important for TEC maintenance and function and their mechanisms of action remain unknown. Here, we demonstrate that miR-205 is highly and preferentially expressed in mTECs during both thymic ontogeny and in the postnatal thymus. This distinct expression is suggestive of functional importance for TEC biology. Genetic ablation of miR-205 in TECs, however, neither revealed a role for miR-205 in TEC function during homeostatic conditions nor during recovery from thymic stress conditions. Thus, despite its distinct expression, miR-205 on its own is largely dispensable for mTEC biology. In order to identify miRNAs differentially expressed in mTECs, we purified cortical thymic epithelial cells (cTECs), mTECs and CD45+ cells as three distinct populations and prepared RNA for microarray analysis. Thymic subsets were FACS-purified from 4-week old NOD wildtype mice. Thymi from 10-12 female mice were pooled together for stromal cell isolation for a total of 3 CD45+, 2 cTEC and 3 mTEC biologic replicates.

2015-07-28 | E-GEOD-68674 | biostudies-arrayexpress

Gene expression in thymic epithelial cells [RNA-seq]

Project description:This study set out to assay the (polyA+) transcriptomes of specific FACS sorted populations of mouse thymic epithelial cells (TEC). Two biological replicates of each of seven murine TEC populations were FACS sorted and sequenced.

2014-09-04 | E-GEOD-53110 | biostudies-arrayexpress

RNA-seq profiling of thymic epithelial cells from Mcl1 knockout and wildtype mice

Project description:T cell differentiation is governed by interactions with thymic epithelial cells (TECs) and defects in this process undermine immune function and tolerance. To uncover new strategies to restore thymic function and adaptive immunity in immunodeficiency, we sought to determine the molecular mechanisms that control life and death decisions in TEC. We created a mouse model which specifically deleted the pro-survival gene Mcl1 in TEC. We found that while BCL-2 and BCL-XL were dispensable for TEC homeostasis, MCL-1 deficiency impacted on TEC as early as E15.5, resulting in early thymic atrophy and T cell lymphopenia, with near complete loss of thymic tissue by 2 months of age. MCL-1 was not necessary for TEC differentiation but was continually required for the survival of medullary TEC, including autoimmune regulator (AIRE) expressing TECs and the maintenance of overall thymic architecture. To understand the molecular mechanisms in more detail, RNA-seq profiling was undertaken of cortical and medullary thymic epithelial cells (cTECs and mTECs) from wildtype and knockout mice.

2017-09-25 | GSE102227 | GEO

Transcription profiling of thymic epithelial cells from C57BL/6 and AIRE knockout mice.

Project description:TEC (B6 vs Aire KO). Thymic epithelial cells from B6 strain and AIRE KO are compared.

2007-12-01 | E-GEOD-2515 | biostudies-arrayexpress

Activation of Inflammation and Metabolic Networks in Age-related Thymic Involution.

Project description:Genetic modeling of thymic involution has demonstrated the importance of individual inflammatory pathways affecting the thymic microenvironment, particularly thymic epithelial cells (TEC). We studied the pathogenic processes in chronological aging of the murine thymus. We used microarrays to elucidate the global gene expression and to identify a leading edge subset of age-associated genes in TEC. Analyses of the TEC transcriptome demonstrated altered expression associated with inflammatory and fatty acid metabolism.

2016-05-06 | GSE81163 | GEO

Thymic mimetic cells function beyond self-tolerance [mimetics]

Project description:To examine the transcriptome of various mimetic thymic epithelial cell populations (CilTEC, MyoTEC, Hetero-post TEC, microfold TEC, endocrine TEC and corneoTEC) we sorted these populations from young WT mice and performed bulk RNAseq

2023-08-28 | GSE236070 | GEO

Next-generation sequencing of cTEC and mTEC isolated from non-pregnant and pregnant females lacking the expression of Klf4 (KO) or not (LOX)

Project description:Stress-induced thymic involution is defined by profound damage to thymic epithelial cells (TECs), resulting in an acute and transient reduction of thymopoietic capacity. During pregnancy, thymic involution is not associated with TEC loss but rather with TEC quality modifications. Study of the mechanisms of TEC maintenance during pregnancy may be of critical importance for identifying new players for thymic regeneration in other models of thymic involution. We report a strong enrichment for motifs recognized by KLF4 based on genes differentially expressed in TECs of pregnant females. Therefore, we studied the impact of Klf4 deletion in TECs during pregnancy by analyzing thymus composition and TEC transcriptome. Conditional Klf4 deletion in homeostatic conditions does not injure thymic integrity. However, pregnant females lacking Klf4 show a disrupted thymus with substantial loss of thymic epithelial cells. Klf4 maintains cTEC number during pregnancy by maintaining cell survival and inhibiting the transition to a mesenchymal state. Our study reveals Klf4 as a protective factor for TECs during pregnancy-associated thymic involution and represents a potential study subject for other models of stress-induced thymic involution.

2022-09-30 | GSE210885 | GEO

Dynamic changes of nonepithelial thymic stroma during thymus organogenesis

Project description:The thymic stroma provides the microenvironment for T cell lineage commitment, development, maturation, and repertoire selection. While the thymic epithelial cell (TEC) compartment is relatively well characterised, a comparably detailed analysis of the non-TEC stromal compartment including the endothelial cells and fibroblasts is currently lacking. Here, we probe the composition of thymic mesenchymal cells and their dynamic change during thymus organogenesis. Using a single cell transcriptomic approach, we identify previously unappreciated heterogeneity within the non-TEC stromal compartment and demonstrate dynamic shifts within non-TEC stromal cell populations over thymic development. We then use a compound heterozygous model (Tbx1+/-Crkl+/-) for 22q11.2DS syndrome to show that significant reductions of multiple mesenchymal subpopulations associated with functional defects and accelerated aging are associated with the thymic hypoplasia observed in this condition. Thus, we provided a comprehensive picture of non-TEC thymic stromal development and their functional defects in a disease model of thymic hypoplasia.

2022-05-13 | GSE163520 | GEO

microRNA expression in thymic epithelial cells

2015-07-28 | GSE68674 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data