Project description:A comparative transcriptome analysis was performed to compare the fruit AZs of the non-shedding E. oleifera variant and from an individual of the same progeny that sheds its ripe fruit normally. The study provides evidence for widespread perturbation to gene expression in the AZ of the non-shedding variant, compared to the normal fruit-shedding control, and allows insight into abscission related functions.
Project description:Salmonella species infect many vertebrate species, and pigs colonized with Salmonella enterica serovar Typhimurium (ST) are usually asymptomatic, making detection of these Salmonella-carrier pigs difficult. The variable fecal shedding of this gram-negative bacteria in such pigs is an important cause of foodborne illness and zoonotic disease. To investigate gene pathways and biomarkers associated with the variance in Salmonella shedding following experimental inoculation, we have initiated the first analysis of the whole blood transcriptional response induced by Salmonella. A population of pigs (n=40) was inoculated with ST and the peripheral blood and feces were collected between 2 and 20 days post-inoculation. Two groups of pigs with either low shedding (LS) or persistent shedding (PS) phenotypes were identified. The global transcriptional changes in response to ST inoculation were identified by Affymetrix Genechip?analysis of peripheral blood RNA at day 0 and day 2 post-inoculation. Forty pigs (n=40) was inoculated with ST. Four low shedding (LS) pigs and six persistent shedding (PS) pigs were identified. Transcriptom of peripheral blood collected at 0 and 2 dpi were identified by Affymetrix Genechip analysis.
Project description:The aim of this study is to assess the global transcriptome changes during the shedding of the flower, which normally takes around 6 or 7 days. We selected four time points (from day 0 to day 6) and three different tissues within the flower bud; distal, abscission and proximal zones with three biological replicates. RNA extraction, library prep and paired end sequencing was performed. Our special interest is try to describe the changes in the abscission zone and the two adjacent tissues in order to get a whole picture of the shedding process. We performed a de novo assembly by Trinity and detected the transcripts and expression changes across spatial and temporal comparisons.
Project description:Salmonella species infect many vertebrate species, and pigs colonized with Salmonella enterica serovar Typhimurium (ST) are usually asymptomatic, making detection of these Salmonella-carrier pigs difficult. The variable fecal shedding of this gram-negative bacteria in such pigs is an important cause of foodborne illness and zoonotic disease. To investigate gene pathways and biomarkers associated with the variance in Salmonella shedding following experimental inoculation, we have initiated the first analysis of the whole blood transcriptional response induced by Salmonella. A population of pigs (n=40) was inoculated with ST and the peripheral blood and feces were collected between 2 and 20 days post-inoculation. Two groups of pigs with either low shedding (LS) or persistent shedding (PS) phenotypes were identified. The global transcriptional changes in response to ST inoculation were identified by Affymetrix Genechip?analysis of peripheral blood RNA at day 0 and day 2 post-inoculation.
Project description:TACE (TNFa Converting Enzyme), is responsible for cleavage (‘shedding’) of membrane-tethered signaling molecules such as TNF of EGFR ligands. TACE interacts with iRhom2, which mediates the exit of TACE from the endoplasmic reticulum. In this study we analyze a new role for iRHOM2, where a fraction of the protein remains in the membrane and the phosphorylation of different residues in its cytoplasmatic tail is necessary for TACE shedding function.
Project description:Myocardial infarction (MI) contributes to cardiac mortality and morbidity. After myocardial infarction the innate immune response is pivotal in clearing of tissue debris as well as scar formation, but exaggerated cytokine and chemokine secretion with subsequent leukocyte infiltration also leads to further tissue damage. Post-translational regulation of cytokine / chemokine signaling occurs via ectodomain shedding through a disintegrin and metalloproteases (ADAMs). Here, we address the value of targeting a previously unknown ADAM10 / CX3CL1 axis in the regulation of neutrophil recruitment early after MI. We show that myocardial ADAM10 is distinctly upregulated in biopsies from patients with ischemia-driven cardiomyopathy and correlates with heart failure progression. Intriguingly, upon MI in mice, pharmacological treatment with the ADAM10 inhibitionor GI254023X as well as genetic cardiomycyte-specific ADAM10 deletion improves survival with markedly enhanced heart function and reduced scar size. Mechanistically, this is driven by abolished ADAM10-mediated CX3CL1 ectodomain shedding followed by diminished IL-1β-dependent inflammation, reduced neutrophil bone marrow egress as well as myocardial tissue infiltration. Genetic cardiomycyte-specific ADAM10 deletion confirmes the small-molecule data and leads to improved cardiac function and reduction in inflammatory markers after ischemic myocardial injury. Thus, our data shows a conceptual insight into how acute MI induces chemotactic signaling via ectodomain shedding in cardiomyocytes.
Project description:Expression data from MDA-MB231 human breast cancer cells treated with metalloproteinase inhibitor (10uM BB94), MEK inhibitor (3uM PD325901), or DMSO control shows substantial overlap in the transcriptional responses arising from MEK and protease inhibition, suggesting a shared mechanism of action. Kinase inhibitor resistance often involves upregulation of poorly understood “bypass” signaling pathways. Here, we show that extracellular proteomic adaptation is one path to bypass signaling and drug resistance. Proteolytic shedding of surface receptors, which can provide negative feedback on signaling activity, is blocked by kinase inhibitor treatment and enhances bypass signaling. In particular, MEK inhibition broadly decreases shedding of multiple receptor tyrosine kinases (RTKs) including HER4, MET, and most prominently AXL, an ADAM10 and ADAM17 substrate, thus increasing surface RTK levels and mitogenic signaling. Progression-free survival of melanoma patients treated with clinical BRAF/MEK inhibitors inversely correlates with RTK shedding reduction following treatment, as measured non-invasively in blood plasma. Disrupting protease inhibition by neutralizing TIMP1 improves MAPK inhibitor efficacy, and combined MAPK/AXL inhibition synergistically reduces tumor growth and metastasis in xenograft models. Altogether, extracellular proteomic rewiring through reduced RTK shedding represents a surprising mechanism for bypass signaling in cancer drug resistance.
Project description:MICA and MICB (MICA/B) are expressed by many human cancers due to cellular stress and tag cells for elimination by cytotoxic lymphocytes through NKG2D receptor activation. However, tumors evade this immune recognition pathway through proteolytic shedding of MICA/B proteins. We rationally designed antibodies targeting the MICA α3 domain, the site of proteolytic shedding, and found that these antibodies prevented loss of cell surface MICA/B by human cancer cells. These antibodies inhibited tumor growth in multiple fully immuno-competent mouse models and also reduced human melanoma metastases in a humanized mouse model. Anti-tumor immunity was mediated mainly by NK cells through activation of NKG2D and CD16 Fc receptors. This novel approach prevents the loss of important immunostimulatory ligands by human cancers and reactivates antitumor immunity.
Project description:Proteolytic ectodomain shedding of membrane proteins is a fundamental mechanism to control the communication between cells and their environment. A key protease for membrane protein shedding is ADAM17, which requires a non-proteolytic subunit, either inactive Rhomboid 1 (iRhom1) or iRhom2 for its activity. While iRhom1 and iRhom2 are coexpressed in most tissues and appear to have largely redundant functions, the brain is an organ with predominant expression of iRhom1. Yet, little is known about the spatio-temporal expression of iRhom1 in mammalian brain and about its function in controlling membrane protein shedding in the nervous system. Here, we demonstrate that iRhom1 is expressed in mouse brain from the prenatal stage to adulthood with a peak in early postnatal development. In the adult mouse brain iRhom1 was widely expressed, including in cortex, hippocampus, olfactory bulb and cerebellum. Proteomic analysis of the secretome of primary neurons and of cerebrospinal fluid (CSF), obtained from iRhom1-deficient and control mice, identified several membrane proteins that require iRhom1 for their shedding in vitro or in vivo. One of these proteins was the ‘multiple-EGF-like-domains protein 10’ (MEGF10), a phagocytic receptor in the brain that is linked to the removal of amyloid and apoptotic neurons. MEGF10 was further validated as an ADAM17 substrate using ADAM17-deficient mouse embryonic fibroblasts. Taken together, this study discovers a role for iRhom1 in controlling membrane protein shedding in the mouse brain, establishes MEGF10 as an iRhom1-dependent ADAM17 substrate and demonstrates that iRhom1 is widely expressed in murine brain.