During sporulation in the budding yeast , proper development of the prospore membrane is necessary for the formation of viable spores. The prospore membrane will eventually become the plasma membrane of the newly formed haploid spore and also serves as the template for the deposition of the spore wall. The prospore membrane is generated de novo during meiosis II and the growing edge of the prospore membrane is associated with the Leading Edge Protein (LEP) complex.
View Article and Find Full Text PDFT cells must migrate to encounter antigen-presenting cells and perform their roles in host defense. Here, we found that autocrine stimulation of the purinergic receptor P2Y11 regulates the migration of human CD4 T cells. P2Y11 receptors redistributed from the front to the back of polarized cells where they triggered intracellular cAMP/PKA signals that attenuated mitochondrial metabolism at the back.
View Article and Find Full Text PDFMeiosis in the budding yeast is used to create haploid yeast spores from a diploid mother cell. During meiosis II, cytokinesis occurs by closure of the prospore membrane, a membrane that initiates at the spindle pole body and grows to surround each of the haploid meiotic products. Timely prospore membrane closure requires , which encodes an STE20 family GCKIII kinase.
View Article and Find Full Text PDFT cells form an immune synapse (IS) with antigen-presenting cells (APCs) to detect antigens that match their TCR. Mitochondria, pannexin-1 (panx1) channels, and P2X4 receptors congregate at the IS where mitochondria produce the ATP that panx1 channels release in order to stimulate P2X4 receptors. P2X4 receptor stimulation causes cellular Ca influx that up-regulates mitochondrial metabolism and localized ATP production at the IS.
View Article and Find Full Text PDFIschemia and reperfusion injury following severe trauma or cardiac arrest are major causes of organ damage in intensive care patients. The brain is particularly vulnerable because hypoxia rapidly damages neurons due to their heavy reliance on oxidative phosphorylation. Therapeutic hypothermia can reduce ischemia-induced brain damage, but cooling procedures are slow and technically difficult to perform in critical care settings.
View Article and Find Full Text PDFBacterial infections and sepsis are leading causes of morbidity and mortality in critically ill patients. Currently, there are no effective treatments available to improve clinical outcome in sepsis. Here, we elucidated a mechanism by which Escherichia coli (E.
View Article and Find Full Text PDFObjectives: Monocytes and macrophages produce interleukin-1β by inflammasome activation which involves adenosine triphosphate release, pannexin-1 channels, and P2X7 receptors. However, interleukin-1β can also be produced in an inflammasome-independent fashion. Here we studied if this mechanism also involves adenosine triphosphate signaling and how it contributes to inflammasome activation.
View Article and Find Full Text PDFT cells must migrate in order to encounter antigen-presenting cells (APCs) and to execute their varied functions in immune defense and inflammation. ATP release and autocrine signaling through purinergic receptors contribute to T cell activation at the immune synapse that T cells form with APCs. Here, we show that T cells also require ATP release and purinergic signaling for their migration to APCs.
View Article and Find Full Text PDFDuring sporulation in Saccharomyces cerevisiae, a double lipid bilayer called the prospore membrane is formed de novo, growing around each meiotic nucleus and ultimately closing to create four new cells within the mother cell. Here we show that SPS1, which encodes a kinase belonging to the germinal center kinase III family, is involved in prospore membrane development and is required for prospore membrane closure. We find that SPS1 genetically interacts with SPO77 and see that loss of either gene disrupts prospore membrane closure in a similar fashion.
View Article and Find Full Text PDFGreen fluorescent protein (GFP) has become an invaluable tool in biological research. Many GFP variants have been created that differ in brightness, photostability, and folding robustness. We have created two hybrid GFP variants, Envy and Ivy, which we placed in a vector for the C-terminal tagging of yeast proteins by PCR-mediated recombination.
View Article and Find Full Text PDFSporulation in the budding yeast Saccharomyces cerevisiae is a developmental program initiated in response to nutritional deprivation. Sps1, a serine/threonine kinase, is required for sporulation, but relatively little is known about the molecular mechanisms through which it regulates this process. Here we show that SPS1 encodes a bona-fide member of the GCKIII subfamily of STE20 kinases, both through phylogenetic analysis of the kinase domain and examination of its C-terminal regulatory domain.
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