Project description:Cardiac mesoderm, a precursor for all cardiovascular lineages, is a promising cell source for basic research and clinical applications. BMP/Nodal/Wnt signaling induces cardiac mesoderm in embryonic stem cells (ESCs); however the molecular mechanism is unclear and the differentiation protocols are labor-intensive. Identification of a master regulator that induces cardiac mesoderm is needed. Here we found that Tbx6 directly reprogrammed mouse fibroblasts into cardiac mesoderm-like cells, which differentiated into cardiomyocytes and smooth muscle cells with addition of lineage-specific transcription factors. In mouse ESCs, BMP/Activin (Nodal) induced Tbx6 in cardiac mesoderm, while inhibition of Tbx6 blocked differentiation into cardiac mesoderm and cardiomyocytes. Conversely, transient expression of Tbx6 induced cardiac mesoderm in ESCs without exogenous factors, and generated all cardiovascular lineages. Mechanistically, Tbx6 directly upregulated Mesp1, inhibited Sox2, and activated BMP/Nodal/Wnt signaling to induce cardiac mesoderm. Thus, Tbx6 acts as a key regulator for cardiac mesoderm induction, and our findings provide new insights into the mechanism of cardiovascular differentiation.
Project description:The ketogenic diet has been successful in promoting weight loss among patients that have struggled with weight gain. This is due to the cellular switch in metabolism that utilizes liver-derived ketone bodies for the primary energy source rather than glucose. Fatty acid transport protein 2 (FATP2) is highly expressed in liver, small intestine, and kidney where it functions in both the transport of exogenous long chain fatty acids (LCFA) and in the activation to CoA thioesters of very long chain fatty acids (VLCFA). We have completed a multi-omic study of FATP2-null (Fatp2-/-) mice maintained on a ketogenic diet (KD) or paired control diet (CD), with and without a 24-hour fast (KD-fasted and CD-fasted) to address the impact of deleting FATP2 under high-stress conditions. Control (wt/wt) and Fatp2-/- mice were maintained on their respective diets for 4-weeks. Afterwards, half the population was sacrificed while the remaining were fasted for 24-hours prior to sacrifice. We then performed paired-end RNA-sequencing on the whole liver tissue to investigate differential gene expression. The differentially expressed genes mapped to ontologies such as the metabolism of amino acids and derivatives, fatty acid metabolism, protein localization, and components of the immune system’s complement cascade, and were supported by the proteome and histological staining.
Project description:The importance of unanchored Ub in innate immunity has been shown only for a limited number of unanchored Ub-interactors. We investigated what additional cellular factors interact with unanchored Ub and whether unanchored Ub plays a broader role in innate immunity. To identify unanchored Ub-interacting factors from murine lungs, we used His-tagged recombinant poly-Ub chains as bait. These chains were mixed with lung tissue lysates and protein complexes were isolated with Ni-NTA beads. Sample elutions were subjected to mass spectrometry (LC-MSMS) analysis.