A hallmark of Listeria (L.) monocytogenes pathogenesis is bacterial escape from maturing entry vacuoles, which is required for rapid bacterial replication in the host cell cytoplasm and cell-to-cell spread. The bacterial transcriptional activator PrfA controls expression of key virulence factors that enable exploitation of this intracellular niche.
View Article and Find Full Text PDFStem cell research has gathered immense attention in the past decade due to the remarkable ability of stem cells for self-renewal and tissue-specific differentiation. Despite having numerous advancements in stem cell isolation and manipulation techniques, there is a need for highly reliable probes for the specific detection of live stem cells. Herein we developed a new fluorescence probe (CDy9) with high selectivity for mouse embryonic stem cells.
View Article and Find Full Text PDFTwo-photon (TP) microscopy has an advantage for live tissue imaging which allows a deeper tissue penetration up to 1 mm comparing to one-photon (OP) microscopy. While there are several OP fluorescence probes in use for pancreatic islet imaging, TP imaging of selective cells in live islet still remains a challenge. Herein, we report the discovery of first TP live pancreatic islet imaging probe; TP-α (Two Photon-alpha) which can selectively stain glucagon secreting alpha cells.
View Article and Find Full Text PDFA better understanding of the cellular and molecular mechanisms involved in the reprogramming of somatic cells is essential for further improvement of induced pluripotent stem (iPS) cell technology. In this study, we enriched for cells actively undergoing reprogramming at different time points by sorting the cells stained with a stem cell-selective fluorescent chemical probe CDy1 for their global gene expression analysis. Day-to-day comparison of differentially expressed genes showed highly dynamic and transient gene expressions during reprogramming, which were largely distinct from those of fully-reprogrammed cells.
View Article and Find Full Text PDFCurrent strategies to monitor reprogramming into induced pluripotent stem cells (iPSCs) are limited in that they rely on the recognition of advanced stage biomarkers or they involve the transduction of genetically-modified cells. These limitations are particularly problematic in high-throughput screenings where cell availability, low cost and a rapid experimental protocol are critical issues. Herein we report the application of a pluripotent stem cell fluorescent probe (i.
View Article and Find Full Text PDFWe report the first fluorescent diamino-chalcone library and its application in the discovery of a mouse embryonic stem cell (mESC) probe. CDg4, a novel green fluorescent mESC probe was discovered through a high-content image based screening of 160 members of the chalcone library. Interestingly, the molecular binding target of CDg4 was identified as the glycogen of the stem cell colony surface, rather than a conventional protein target from an intracellular source.
View Article and Find Full Text PDFWe report the first solid phase synthesis of a xanthone library CX and its application to embryonic stem cell probe development. The CX library was further derivatised with an activated ester resin to provide an acetylated CX (CXAC) library. Screening of these libraries led to the discovery of a novel fluorescent mESC probe, CDb8.
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