Biology subjects

Lasda, E.

Publications and source records attributed to Lasda, E..

3 recordsLinked to original sources

bioRxiv2024

IL-27 Stablizes Myc-Mediated Transcription In Memory-Fated, Vaccine-Elicited CD8+ T Cells

Protection from pathogens relies on both humoral (antibody-mediated) and cellular (T cell-mediated) responses. While infections robustly elicit both types of immunity, currently approved vaccine adjuvants largely fail to induce T cell responses on par with that instigated by infections. Our goal was to investigate the transcriptional programming that supports the formation of CD8+ T cells elicited by subunit vaccines compared to those elicited by infections. Our data show that vaccine-elicited T cells represent a transcriptionally unique subset of activated T cells with high proliferative capacity and a memory cell fate. This relies on IL-27 signaling, which stabilizes c-Myc and thereby supports the biomass acquisition necessary for clonal expansion. Collectively, our findings reveal that subunit vaccine-elicited T cells uniquely combine aspects of both memory and effector T cell subsets, and selectively utilize IL-27 signaling to sustain the clonal expansion of cells dedicated to a memory fate. One Sentence SummaryIn contrast to infection, subunit vaccines induce a distinct population of CD8+ T cells with memory fate characteristics which maintain their proliferative capacity during the expansion phase through IL-27 receptor signaling.

immunology↗

bioRxiv2022

Massively Parallel Dissection of RNA in RNA-protein interactions in vivo

Many of the biological functions performed by RNA are mediated by RNA-binding proteins (RBPs), and understanding the molecular basis of these interactions is fundamental to molecular biology. Here, we present MPRNA-immunoprecipitation (MPRNA-IP), an adaptation of the previously developed massively parallel RNA assay (MPRNA), and a new avenue for in vivo high-throughput dissection of RNA-protein interactions. By using custom pools of tens of thousands of RNA sequences containing systematically designed truncations and mutations, we are able to identify RNA domains, sequences, and secondary structures necessary and sufficient for protein binding in a single experiment. We show that this approach is successful for multiple RNAs of interest including NORAD, MS2, and human telomerase RNA, and we describe statistical models for identifying RNA domains and parsing the structural contributions of RNA in these interactions. By blending modern and classical approaches, MPRNA-IP provides a novel high-throughput way to elucidate RNA-based mechanisms behind RNA-protein interactions.

genomics↗

bioRxiv2022

The lncRNA Firre functions as a transcriptional activator from a distance

Numerous studies have now demonstrated that lncRNAs can influence gene expression programs leading to cell and organismal phenotypes. Typically, lncRNA perturbations and concomitant changes in gene expression are measured on the timescale of many hours to days. Thus, we currently lack a temporally grounded understanding of the primary, secondary, and tertiary relationships of lncRNA-mediated transcriptional and epigenetic regulation - despite being a prerequisite to elucidating lncRNA mechanisms. To begin to address when and where a lncRNA regulates gene expression, we genetically engineered cell lines to temporally induce the lncRNA Firre. Using this approach, we were able to monitor lncRNA transcriptional regulatory events from 15 min to four days. We observed that upon induction, Firre RNA regulates epigenetic and transcriptional states, in trans, within 30 min. These early regulatory events result in much larger transcriptional changes after twelve hours, well before current studies monitor lncRNA regulation. Moreover, Firre-mediated gene expression changes are epigenetically remembered for days. Overall, this study suggests that lncRNAs can rapidly regulate gene expression by establishing persistent epigenetic and transcriptional states.

genomics↗