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Biology subjects

Steiner, E.

Publications and source records attributed to Steiner, E..

3 recordsLinked to original sources

Spatial transcriptomics of T and B cell receptors uncovers lymphocyte clonal dynamics in human tissue.

The spatial distribution of lymphocyte clones within tissues is critical to their development, selection, and expansion. We have developed Spatial Transcriptomics of VDJ sequences (Spatial VDJ), which maps immunoglobulin and TR antigen receptors in human tissue sections. Spatial VDJ captures lymphocyte clones matching canonical T, B, and plasma cell distributions in tissues and amplifies clonal sequences confirmed by orthogonal methods. We confirm spatial congruency between paired receptor chains, develop a computational framework to predict receptor pairs, and link the expansion of distinct B cell clones to different tumor-associated gene expression programs. Spatial VDJ delineates B cell clonal diversity, class switch recombination, and lineage trajectories within their spatial context. Taken together, Spatial VDJ captures lymphocyte spatial clonal architecture across tissues, which could have important therapeutic implications. One-Sentence SummarySpatial transcriptomics-based technology co-captures T and B cell receptors within their anatomical niche in human tissue.

immunology↗

Targeting RNA:Protein Interactions with an Integrative Approach Leads tothe Identification of Potent YB-1 Inhibitors

RNA-binding proteins are promising targets for developing new molecules of therapeutic interest. Nevertheless, targeting RNA:Protein interfaces is hampered by the lack of methods able to detect these interactions in cells while being amenable to High Content Screening. Here, we adapt the microtubule bench assay to score small molecules targeting interactions of endogenous mRNA with a specific protein in cells and demonstrate its robustness by targeting YB-1 (YBX-1 gene), a mRNA-binding protein involved in cancer progression and resistance to chemotherapy. The implementation of an integrative approach led to the identification of 22 hits validated by NMR and MD simulations of which 11 were found to significantly interfere with the binding of mRNA to YB-1 in cells at low micromolar concentrations. One of our leads is P1, an FDA-approved PARP-1 inhibitor. This work shows the potential of our integrative approach and paves the way for the development of RNA:Protein Interaction inhibitors.

biophysics↗

A conserved superlocus regulates above- and belowground root initiation

During plant post-embryonic growth new meristems and associated stem cells form in different development contexts in order to respond to environmental cues. While underground lateral roots initiate from designated cells in the main root, an unknown mechanism allows cells to bypass the root/shoot identity trajectory and generate shoot-borne-roots. Using single-cell profiling of tomato (Solanum lycoperiscum) stems we isolated a rare transient cell population that serve as progenitors for shoot-borne-root meristems. Analysis of this population identified a transcription factor required for the formation of shoot-borne-roots which we named SHOOT BORNE ROOTLESS (SBRL). Evolutionary analysis revealed that SBRL function is deeply conserved in angiosperms and that it arose as part of an ancient duplicated superlocus, only lost in root-less plants, containing both shoot-borne and lateral root initiation regulators. We propose that the ability to activate a common transition state with context-specific regulators allows the remarkable developmental plasticity found in plants. One Sentence SummaryHighly conserved superlocus of LBD genes, acting within an early transition identity, regulates shoot-borne and lateral root formation.

plant biology↗