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  - 
TY  - JOUR
A1  - Riedel, Alice
A1  - Mofolo, Boitumelo
A1  - Avota, Elita
A1  - Schneider-Schaulies, Sibylle
A1  - Meintjes, Ayton
A1  - Mulder, Nicola
A1  - Kneitz, Susanne
T1  - Accumulation of Splice Variants and Transcripts in Response to PI3K Inhibition in T Cells
JF  - PLoS ONE
N2  - Background
Measles virus (MV) causes T cell suppression by interference with phosphatidylinositol-3-kinase (PI3K) activation. We previously found that this interference affected the activity of splice regulatory proteins and a T cell inhibitory protein isoform was produced from an alternatively spliced pre-mRNA.

Hypothesis
Differentially regulated and alternatively splice variant transcripts accumulating in response to PI3K abrogation in T cells potentially encode proteins involved in T cell silencing.

Methods
To test this hypothesis at the cellular level, we performed a Human Exon 1.0 ST Array on RNAs isolated from T cells stimulated only or stimulated after PI3K inhibition. We developed a simple algorithm based on a splicing index to detect genes that undergo alternative splicing (AS) or are differentially regulated (RG) upon T cell suppression.

Results
Applying our algorithm to the data, 9% of the genes were assigned as AS, while only 3% were attributed to RG. Though there are overlaps, AS and RG genes differed with regard to functional regulation, and were found to be enriched in different functional groups. AS genes targeted extracellular matrix (ECM)-receptor interaction and focal adhesion pathways, while RG genes were mainly enriched in cytokine-receptor interaction and Jak-STAT. When combined, AS/RG dependent alterations targeted pathways essential for T cell receptor signaling, cytoskeletal dynamics and cell cycle entry.

Conclusions
PI3K abrogation interferes with key T cell activation processes through both differential expression and alternative splicing, which together actively contribute to T cell suppression.
KW  - T cells
KW  - gene regulation
KW  - alternative splicing
KW  - measles virus
KW  - T cell receptors
KW  - reverse transcriptase-polymerase chain reaction
KW  - cell cycle and cell division
KW  - TCR signaling cascade
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130335
VL  - 8
IS  - 2
ER  -