Project description:Methods currently available to estimate the post-mortem submerged interval (PMSI) of cadavers in water suffer from poor accuracy, being mostly based on morphological examination of the remains. Proteins present within bones have recently attracted more attention from researchers interested in the estimation of the post-mortem interval (PMI) in terrestrial environments. Despite the great potential of proteomic methods for PMI estimation, their application to aquatic environments has not yet been explored. In this study, we examined whether four different types of aquatic environment (tap water, saltwater, pond water and chlorinated water) affected the proteome of mice bones with increasing PMSIs (from zero to three weeks).
Project description:Microfluidic deterministic barcoding of mRNAs and proteins in tissue slides followed by high throughput sequencing enables the construction of high-spatial-resolution multi-omics atlas at the genome scale. Applying it to mouse embryo tissues revealed major tissue (sub)types in early-stage organogenesis, brain micro-vasculatures, and the fine structure of an optical vesicle at the single-cell-layer resolution.
Project description:Bacterial quorum sensing (QS) systems are characterized by the regulated biogenesis and sensing of specialized signaling molecules. Here, we describe a peptide, Qsp1, secreted by the fungal pathogen Cryptococcus neoformans. Mutants lacking Qsp1 are attenuated for infection, pulmonary accumulation, and growth within macrophages. Qsp1 promotes density-dependent cell wall integrity and resistance to extreme environments. Qsp1 is also required for a secreted aspartyl protease activity required for virulence. Further biochemical and large-scale genetic investigations reveal that cleavage of Qsp1 from the C-terminal of a pro-peptide requires a cell-associated serine protease and Qsp1 sensing requires a predicted oligopeptide importer. Strikingly, these features closely mirror the hallmarks of a peptide-based QS system found in gram-positive bacteria, despite no ancestral relationship between individual components. Our studies thus reveal a convergently evolved, peptide-based QS system required for the virulence of a fungal pathogen.