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Rooijers, K.

Publications and source records attributed to Rooijers, K..

3 recordsLinked to original sources

Mapping the dynamic RNA binding proteome in human effector T 1 cells identifies differentiation and cytotoxicity regulators

RNA-binding proteins (RBPs) are key regulators of T cell function by controlling (m)RNA fate and fine-tuning protein expression dynamics. Dysregulated RBPs can drive immune diseases and malignancies, highlighting their potential as therapeutic targets. To achieve this, a systematic analysis of the dynamic RBP-RNA interactions is required. Here, we mapped the RNA-binding proteome in human T cells and measured its alterations upon T cell activation using orthogonal organic phase separation (OOPS), analysed with PROMOGEB, a Bayesian linear regression model. This approach uncovered the intricate RNA-binding dynamics of the RBProteome. Gene-editing of such dynamic RNA binders revealed that TUT1 (Star-PAP) maintains the integrity of the T cell differentiation program, and that mutating SF3A1 enhanced the cytotoxic molecule expression and thus target cell killing. Our work provides the most comprehensive analysis of the effector T cell RBProteome to date and shows the potential of identifying RBPs and their binding dynamics as therapeutic agents. TeaserOOPS analysed with PROMOGEB maps RBP dynamics in human Teff cells, identifying TUT1 and SF3A1 as regulators of T cell fidelity.

immunology↗

mTOR signaling promotes cytokine production in T cells through 3UTR-mediated translation control

T cells are key contributors to clear our body from infected and malignant cells. When T cells respond to target cells, they undergo profound translational alterations. The evolutionary and highly conserved kinase mammalian target of rapamycin (mTOR) is a central mediator of T cell differentiation, homeostasis, and T cell activation, including the production of the key pro-inflammatory cytokines TNF, IL2, and IFN{gamma}. mTOR was shown to execute its translation activity through TOP motifs located in the 5 Untranslated region (5UTR) of its target genes. Here, we uncovered a distinct mechanism of mTOR signaling on cytokine production in T cells, which is under control of the 3UTR. Even though non-classical TOP motifs are present in cytokine 3UTRs, they do not contribute to mTOR-mediated translation regulation. Rather, AU-rich elements (AREs) are required for mTOR-mediated cytokine production. Furthermore, we discovered that the RNA binding protein DDX21 binds to 3UTR AREs and confers the mTOR-mediated translation control. In conclusion, we here present a previously unappreciated ARE-dependent, 3UTR-mediated mode of action that mTOR employs to regulate cytokine production.

immunology↗

Simultaneous quantification of protein-DNA contacts and transcriptomes in single cells

The epigenome plays a critical role in regulating gene expression in mammalian cells. However, understanding how cell-to-cell heterogeneity in the epigenome influences gene expression variability remains a major challenge. Here we report a novel method for simultaneous single-cell quantification of protein-DNA contacts with DamID and transcriptomics (scDamID&T). This method enables quantifying the impact of protein-DNA contacts on gene expression from the same cell. By profiling lamina-associated domains (LADs) in human cells, we reveal different dependencies between genome-nuclear lamina (NL) association and gene expression in single cells. In addition, we introduce the E. coli methyltransferase, Dam, as an in vivo marker of chromatin accessibility in single cells and show that scDamID&T can be utilized as a general technology to identify cell types in silico while simultaneously determining the underlying gene-regulatory landscape. With this strategy the effect of chromatin states, transcription factor binding, and genome organization on the acquisition of cell-type specific transcriptional programs can be quantified.

molecular biology↗