Project description:Our specific aim is to examine differential expression of sulf-1 and sulf-2, enzymes involved in heparan sulfate biosynthesis, as well as Wnt ligands and Wnt signaling mediators during corneal wound healing using a mouse corneal scratch model. The specific structural features of heparan sulfate underlie its role in modulating cellular responses to growth factors such as the Wnts. Heparan sulfate 6-O-endosulfatases (sulf-1 and sulf-2) remove 6-O sulfate group from trisulfated disaccharides present on heparan sulfate chains. Our preliminary results suggest that sulf-1 is upregulated at the protein level in the epithelial cells of wounded mouse corneas, as compared to the undamaged contralateral eye. Modulation of heparan sulfate proteoglycan expression and/or structural modifications of its chains might be an important aspect of the regulation of epithelial cell migration and proliferation during wound healing.
Project description:Our specific aim is to examine differential expression of sulf-1 and sulf-2, enzymes involved in heparan sulfate biosynthesis, as well as Wnt ligands and Wnt signaling mediators during corneal wound healing using a mouse corneal scratch model. The specific structural features of heparan sulfate underlie its role in modulating cellular responses to growth factors such as the Wnts. Heparan sulfate 6-O-endosulfatases (sulf-1 and sulf-2) remove 6-O sulfate group from trisulfated disaccharides present on heparan sulfate chains. Our preliminary results suggest that sulf-1 is upregulated at the protein level in the epithelial cells of wounded mouse corneas, as compared to the undamaged contralateral eye. Modulation of heparan sulfate proteoglycan expression and/or structural modifications of its chains might be an important aspect of the regulation of epithelial cell migration and proliferation during wound healing. RNA preparations from four different conditions, were sent to Microarray Core (E). Gene expression was examined in triplicates at 2 time points (8 and 24 hrs post-wounding: 6 arrays), using the contralateral eye as a control at one time point as a control (3 arrays). To account for a systemic response (i.e. bilateral inflammation) to the corneal wounding, corneas of non-wounded mice (3 arrays) were used. The RNA was amplified, labeled, and hybridized to the GLYCOv3 microarrays.
Project description:Microarray analysis to examine glycan-related gene expression in idiopathic pulmonary fibrosis Heparan sulfate 6-O-endosulfatases (Sulf1 and Sulf2) remove 6-O sulfate groups from heparan sulfate intra-chain sites on the cell surface and in the extracellular matrix, and modulate the functions of many growth factors and morphogens including FGF, Wnt and TGF-beta. Works from our laboratory have shown that TGF-beta 1 induces Sulf1 and Sulf2 expression in a cell-type specific manner in the lung, specifically Sulf1 in lung fibroblasts and Sulf2 in type II alveolar epithelial cells. Interestingly TGF-beta 1-induced Sulf1 and Sulf2 in turn modulate TGF-beta 1 function in culture. The aim of this study is to examine the expression of Sulf1 and Sulf2 as well as other glycan-related genes (heparan biosynthetic enzymes, TGF-beta, FGF and Wnt signaling pathway components) in human idiopathic pulmonary fibrosis (IPF) lungs compared to normal lung samples. We will examine gene expression in triplicate samples from RNA of total lung homogenates from IPF and control (normal) lungs
Project description:Breast cancer mortality results from incurable recurrent tumors, putatively seeded by dormant, therapy-refractory residual tumor cells (RTCs). Understanding the mechanisms enabling RTC survival is therefore essential for improving patient outcomes. We derived a dormancy-associated RTC signature that mirrors the transcriptional response to neoadjuvant chemotherapy in patients and is enriched for extracellular matrix-related pathways. In vivo CRISPR-Cas9 screening of dormancy-associated candidate genes identified the galactosyltransferase B3GALT6 as a functional regulator of RTC fitness. B3GALT6 is required for the linkage of glycosaminoglycans (GAGs) to proteins to generate proteoglycans and its germline loss-of-function causes skeletal dysplasias. We determined that B3GALT6-mediated biosynthesis of heparan sulfate GAGs predicts poor patient outcomes, promotes tumor recurrence by enhancing dormant RTC survival in multiple contexts, and does so via a B3GALT6-heparan sulfate/HS6ST1-heparan 6-O-sulfation/FGF1-FGFR2 signaling axis. These findings implicate B3GALT6 in cancer and suggest targeting of FGFR2 signaling as a novel approach to eradicate dormant RTCs, thereby preventing recurrence.
Project description:Heparan sulfate proteoglycans (HSPGs) are expressed on virtually all animal cells and are involved in many important biological processes. Each HSPG consists of a core protein with one or more covalently attached linear heparan sulfate (HS) chains composed of alternating glucosamine and uronic acids that are heterogeneously N- and O-sulfated. The arrangement and orientation of the sulfated sugar residues of HS specify the location of distinct ligand binding sites on the cell surface, and these modifications can vary temporally during development and spatially across tissues. While most of the enzymes involved in HS biosynthesis have been studied extensively, much less information exists regarding the specific mechanisms that give rise to the variable composition and binding properties of HS.
Project description:Heparan sulfate proteoglycans (HSPGs) are expressed on virtually all animal cells and are involved in many important biological processes. Each HSPG consists of a core protein with one or more covalently attached linear heparan sulfate (HS) chains composed of alternating glucosamine and uronic acids that are heterogeneously N- and O-sulfated. The arrangement and orientation of the sulfated sugar residues of HS specify the location of distinct ligand binding sites on the cell surface, and these modifications can vary temporally during development and spatially across tissues. While most of the enzymes involved in HS biosynthesis have been studied extensively, much less information exists regarding the specific mechanisms that give rise to the variable composition and binding properties of HS.
Project description:In order to examine the role of macrophage heparan sulfate proteoglycans in atherogenesis, we inactivated the biosynthetic gene N-acetylglucosamine N-deacetylase-N-sulfotransferase 1 (Ndst1) in macrophages. In order to determine the impact of altering Ndst1 expression, we crossbred mice bearing a conditional loxP-flanked (“floxed”) allele of Ndst1 (Ndst1f/f) to transgenic mice expressing the bacterial Cre recombinase under control of the lysozyme 2 promoter (LysMCre) to drive inactivation of the gene in myeloid cells. We compared the transcriptome of bone marrow derived macrophages from Ndst1f/fLysMCre- and Ndst1f/fLysMCre+ macrophages in basal growth medium and after foam cell conversion using 50µg/ml of aggregated LDL (agLDL) to asses the impact of altered macrophage heparan sulfate sulfation on gene expression.
Project description:In order to examine the role of macrophage heparan sulfate proteoglycans in atherogenesis, we inactivated the biosynthetic gene N-acetylglucosamine N-deacetylase-N-sulfotransferase 1 (Ndst1) in macrophages. In order to determine the impact of altering Ndst1 expression, we crossbred mice bearing a conditional loxP-flanked (M-bM-^@M-^\floxedM-bM-^@M-^]) allele of Ndst1 (Ndst1f/f) to transgenic mice expressing the bacterial Cre recombinase under control of the lysozyme 2 promoter (LysMCre) to drive inactivation of the gene in myeloid cells. We compared the transcriptome of bone marrow derived macrophages from Ndst1f/fLysMCre- and Ndst1f/fLysMCre+ macrophages in basal growth medium and after foam cell conversion using 50M-BM-5g/ml of aggregated LDL (agLDL) to asses the impact of altered macrophage heparan sulfate sulfation on gene expression. Total RNA obtained from bone marrow derived macrophages (BMDM) derived form two wild-type and two Ndfst1-deficient mice before and after foam cell conversion and analyzed in diplicate (n=4 for each conditions; total of 4 conditions)
Project description:Microarray analysis to examine glycan-related gene expression in idiopathic pulmonary fibrosis Heparan sulfate 6-O-endosulfatases (Sulf1 and Sulf2) remove 6-O sulfate groups from heparan sulfate intra-chain sites on the cell surface and in the extracellular matrix, and modulate the functions of many growth factors and morphogens including FGF, Wnt and TGF-beta. Works from our laboratory have shown that TGF-beta 1 induces Sulf1 and Sulf2 expression in a cell-type specific manner in the lung, specifically Sulf1 in lung fibroblasts and Sulf2 in type II alveolar epithelial cells. Interestingly TGF-beta 1-induced Sulf1 and Sulf2 in turn modulate TGF-beta 1 function in culture.
Project description:Sepsis patients are at increased risk for hospital-acquired pulmonary infections, potentially due to post-septic immunosuppression known as the compensatory anti-inflammatory response syndrome (CARS). CARS has been attributed to leukocyte dysfunction, with an unclear role for endothelial cells. The pulmonary circulation is lined by an endothelial glycocalyx, a heparan sulfate-rich layer essential to pulmonary homeostasis. Heparan sulfate degradation occurs early in sepsis, leading to lung injury. Endothelial synthesis of new heparan sulfates subsequently allows for glycocalyx reconstitution and endothelial recovery. We hypothesized that remodeling of the reconstituted endothelial glycocalyx, mediated by alterations in the endothelial machinery responsible for heparan sulfate synthesis, contributes to CARS. Our experimental animal model of CARS recapitulated post-septic immunosuppression, coincidentally with structural remodeling of endothelial glycocalyx heparan sulfate. We used microarray to identify which heparan sulfate modifying enzyme is responsible for the remodeling of post-septic reconstituted glycocalyx, characterized with enrichment of heparan sulfate disaccharides sulfated at the 6-O position of glucosamine.