Biology subjects

Ro, T.

Publications and source records attributed to Ro, T..

4 recordsLinked to original sources

bioRxiv2025

Phospotyrosine proteomics reveals novel Zap70 and Itk pathway targets downstream of TCR and CAR in Jurkat T cells

{zeta}-associated protein of 70 kDa (Zap70) and interleukin-2-inducible T cell kinase (Itk) propagate the primary and CD28-integrated phosphotyrosine (pY) signalling, respectively, to achieve full T cell activation. Despite their canonical roles in T cell activation, our understanding of how each kinase controls canonical and noncanonical pY signalling is incomplete. Here, using three T cell activation methods (soluble antibodies, APC- pMHC/TCR, and CD19-CAR/Raji), we evaluated the effects of two novel inhibitors, RDN2150 (RDN, Zap70) and Soquelitinib (Soq, Itk), on T cell activation. We validated the published working concentrations of RDN and Soq on phosphorylation of key T cell signalling proteins and on T cell activation markers, finding that RDN provides more complete inhibition of T cell signalling and activation. We used LC-MS/MS to evaluate how RDN and Soq treatment affected the phosphotyrosine (pY) signalling and proteome of T cells, finding that RDN, as opposed to Soq, completely downregulated the TCR signalling pathway. Finally, we identified new, noncanonical pY sites responsive to RDN and Soq, providing new insights into the pathways regulated by Zap70 and Itk. Together, our work provides a basis for further study on RDN and Soq, as well as a molecular roadmap for the effects of these inhibitors.

immunology↗

bioRxiv2025

Inclusion of the ζ-chain drives phosphotyrosine signalling in CD19-CAR T cells

Although chimeric antigen receptor (CAR) T cell therapy has revolutionised individualised cancer therapies for relapsed/refractory lymphomas, signalling mechanisms underlying CAR T activation remain incompletely understood, especially among the three generations of CAR T exploiting different signalling domains. Here, using Jurkat T cell as a model, we investigate how costimulation influences tyrosine phosphorylation cascades using LC-MS/MS based phosphotyrosine (pY) proteomics and CD69 expression in the presence of small molecule inhibitors of key TCR signalling regulators. We find that including the {zeta}-chain in first ({zeta}-CAR), second (28{zeta}-CAR and BB{zeta}-CAR), and third (28BB{zeta}-CAR) generation CARs largely determines pY signalling, irrespective of costimulation. Further, we show that the phosphatase activity of PTPN22 and SHP-1 are largely negligible for activation of CARs, but indiscriminate inhibition of phosphatases using Pervanadate (PV) selectively activates BB{zeta}-CARs without antigen encounter. Finally, we find that selective, partial inhibition of Itk using Soquelitinib reduces basal CD69 expression in Jurkat CAR T cells while maintaining their ability to activate in response to antigen. Our data suggest that the {zeta}-chain determines the pY signalling profile of CD19-CAR Jurkat T cells and that Itk may drive antigen-independent CD19-CAR activation.

cancer biology↗

bioRxiv2022

Sound Frequency Predicts the Bodily Location of Auditory-Induced Tactile Sensations in Synesthetic and Ordinary Perception

For individuals who experience sound-touch synesthesia, sounds consistently evoke strong, localized sensations on the body. Interestingly, visual and auditory information can also evoke bodily sensations in ordinary perception, such as the sight or sound of a mosquito producing phantom sensations of touch. We systematically investigated the functional relationship between sound frequency and several characteristics of induced tactile experiences in synesthetes and controls. Sound frequency strongly predicted the location of tactile sensations on the body in both synesthetes and controls. Synesthetes felt sound-induced touch more frequently and in significantly more concentrated locations on their bodies compared to sound-induced touch perceptions in controls. This spatial distribution of touch reflects a behavioral mapping between tonotopy and somatotopy that suggests the involvement of early, tonotopically- and somatotopically-organized brain areas. Sound frequency also predicted the hardness, roughness, and sharpness of tactile sensations in both groups. Together, these findings highlight a strong similarity between auditory-tactile mappings in synesthetic and ordinary perception, suggesting that synesthesia only differs in the strength of the mappings and therefore is on a spectrum with ordinary perception. Furthermore, these findings offer insights into the possible underlying neural mechanisms of sound-touch mappings, suggesting that they rely on cross-modal neural pathways already in use in ordinary perception.

neuroscience↗

bioRxiv2018

Anterior prefrontal cortex mediates implicit inferences

Frequent experience with regularities in our environment allows us to use predictive information to guide our decision process. However, contingencies in our environment are not always explicitly present and sometimes need to be inferred. Heretofore, it remained unknown how predictive information guides decision-making when explicit knowledge is absent and how the brain shapes such implicit inferences. In the present experiment, participants performed a discrimination task in which a target stimulus was preceded by a predictive cue. Critically, participants had no explicit knowledge that some of the cues signaled an upcoming target, allowing us to investigate how implicit inferences emerge and guide decision-making. Despite unawareness of the cue-target contingencies, participants were able to use implicit information to improve performance. Concurrent EEG recordings demonstrate that implicit inferences rely upon interactions between internally and externally oriented networks, whereby anterior prefrontal regions inhibit right parietal cortex under internal implicit control.\n\nSignificanceRegularities in our environment can guide our behavior providing information about upcoming events. Interestingly, such predictive information does not need to be explicitly represented in order to effectively guide our decision process. Here, we show how the brain engages in such real-world data mining and how implicit inferences emerge. We employed a contingency cueing task and demonstrate that implicit inferences influenced responses to subsequent targets despite a lack of awareness of cue-target contingencies. Further, we show that these implicit inferences emerge through interactions between internally- and externally-oriented neural networks. The current results highlight the importance of the anterior prefrontal cortex in transforming external events into predictive internalized models of the world.

neuroscience↗