Project description:Small RNAs are emerging as important molecules for cross-species communication. Thanks to available and affordable sequencing technologies it is now possible to sequence small RNAs (sRNA-Seq) present in samples of interacting organisms. A first step when analyzing sRNA-Seq of two interacting species is to determine which sequences are being produced by which organism. Due to their small size (18-30), small RNAs could easily map to both host and parasite genomes. Here we produced data for Mus musculus intestinal epithelial cells treated with Extracellular Vesicles (EV) produced by the parasitic nematode Heligmosomoides bakeri.
Project description:MARTX toxins are large single polypeptide bacterial toxins that translocate multiple cytotoxic and functionally independent effector domains into the cytosol of a target eukaryotic cell. Pandemic Vibrio cholerae El Tor O1 strains secrete a MARTX toxin with three effector domains — the actin crosslinking domain (ACD), the Rho inactivation domain (RID), and the alpha/beta-hydrolase domain (ABH) — to regulate innate immunity and enhance colonization. The goal of this study was to compare changes in the transcriptome of human intestinal epithelial cells (IECs) treated with V. cholerae modified to secret a toxin with only one effector domain to the transcriptome of cells treated with V. cholerae secreting the wild type MARTX toxin that delivers all three effector domains simultaneously. We demonstrate that when all three effectors are delivered there is no change in transcriptional response of IECs compared to untreated cells. However, when only ACD is delivered, transcriptional profiling revealed a significant proinflammatory response is activated. These data suggests that V. cholerae may utilize co-delivery of RID and/or ABH to silence the intestinal immune response to ACD activity. These data provide insight into how the V. cholerae MARTX toxin effector domains function together to alter the innate immune response of IECs during bacterial infection.
Project description:The intestinal epithelium is a key physical interface that integrates dietary and microbial signals to regulate nutrient uptake and mucosal homeostasis. Intestinal epithelial cells (IECs) have a high turnover rate driven by the death of terminally differentiated cells with concurrent stem cell proliferation, a process critical for maintaining intestinal homeostasis and protecting against mucosal inflammation. The transcriptional programs that regulate IEC quiescence, proliferation, and differentiation have been well-characterized. However, how gene expression networks critical for IEC functions are regulated at the post-transcriptional level during homeostasis or inflammatory disease remains poorly understood. Herein, we show that a conserved family of microRNAs, miR-181, is significantly downregulated in IECs from patients with inflammatory bowel disease and mice with chemical-induced colitis. Strikingly, we showed that miR-181 expression within IECs, but not the hematopoietic system, is required for protection against the development of severe colonic inflammation in response to epithelial injury in mice. Mechanistically, we showed that miR-181 expression increases the proliferative capacity of IECs, likely through the regulation of Wnt signaling, independently of gut microbiota composition. As epithelial reconstitution is crucial for restoring intestinal homeostasis after injury, the miR-181 family represents a potential novel therapeutic target in IECs for protection against severe intestinal inflammation.
