Effects of StcE treatment on in vitro brain endothelial cell line bEnd.3
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE268263 | GEO | 2024/12/17
REPOSITORIES: GEO
Similar Datasets
Project description:Symbiotic interactions between humans and our communities of resident gut microbes (microbiota) play many roles in health and disease. Some gut bacteria utilize mucus as a nutrient source and can under certain conditions damage the protective barrier it forms, increasing disease susceptibility. We investigated how Ruminococcus torques—a known mucin-degrader that remains poorly studied despite its implication in inflammatory bowel diseases (IBDs)— degrades mucin glycoproteins or their component O-linked glycans to understand its effects on the availability of mucin-derived nutrients for other bacteria. We found that R. torques utilizes both mucin glycoproteins and released oligosaccharides from gastric and colonic mucins, degrading these substrates with a panoply of mostly constitutively expressed, secreted enzymes. Investigation of mucin oligosaccharide degradation by R. torques revealed strong fucosidase, sialidase and b1,4-galactosidase activities. There was a lack of detectable sulfatase and weak β1,3-galactosidase degradation, resulting in accumulation of glycans containing these structures on mucin polypeptides. While the Gram-negative symbiont, Bacteroides thetaiotaomicron grows poorly on mucin glycoproteins, we demonstrate a clear ability of R. torques to liberate products from mucins, making them accessible to B. thetaiotaomicron. This work underscores the diversity of mucin-degrading mechanisms in different bacterial species and the probability that some species are contingent on others for the ability to more fully access mucin-derived nutrients. The ability of R. torques to directly degrade a variety of mucin and mucin glycan structures and unlock released glycans for other species suggests that it is a keystone mucin degrader, which may contribute to its association with IBD.
2024-06-19 | GSE262875 | GEO
Project description:Dr. Clausen's laboratory is interested in the structure, biosynthesis and genetic regulation of glycoconjugates, with a major focus on mucins. This laboratory is studying the glycosylation and secretion process of mucins and biological functions involving mucins. This lab is also interested in receptor modulation mediated by glycosylation or through glycosphingolipids. We have a particular interest in understanding how mucin type O-glycosylation is regulated. Mucin type O-glycosylation is controlled by the ppGalNAc-transferase multigene family. An estimated 23 iso-forms belong to this family, so the specific involvement of each individual iso-form in any given organ seems complex to understand. An initial attempt to comprehend how this multigene family regulates mucin type O-glycosylation, is to get insight into which iso-forms are expressed in different organs and cell types. For this reason we have generated monoclonal antibodies towards 7 iso-forms, and the list of ppGalNAc-T iso-form specific monoclonals is currently growing. We have done some immuno histochemistry on lung using the available monoclonals, but are keen on assessing the number of ppGalNAc-T's expressed in lung as determined this Glyco-array. We have focused on lung because a number of ppGalNAc-T acceptor polypeptides, belonging to the mucin gene family, are expressed in this organ. An RNA sample pooled from two independent adult human healthy lung tissue samples was analyzed
2010-11-30 | E-GEOD-25712 | biostudies-arrayexpress
Project description:Symbiotic interactions between humans and our communities of resident gut microbes (microbiota) play many roles in health and disease. Some gut bacteria utilize mucus as a nutrient source and can under certain conditions damage the protective barrier it forms, increasing disease susceptibility. We investigated how Ruminococcus torques—a known mucin-degrader that remains poorly studied despite its implication in inflammatory bowel diseases (IBDs)— degrades mucin glycoproteins or their component O-linked glycans to understand its effects on the availability of mucin-derived nutrients for other bacteria. We found that R. torques utilizes both mucin glycoproteins and released oligosaccharides from gastric and colonic mucins, degrading these substrates with a panoply of mostly constitutively expressed, secreted enzymes. Investigation of mucin oligosaccharide degradation by R. torques revealed strong fucosidase, sialidase and 1,4-galactosidase activities. There was a lack of detectable sulfatase and weak β1,3-galactosidase degradation, resulting in accumulation of glycans containing these structures on mucin polypeptides. While the Gram-negative symbiont, Bacteroides thetaiotaomicron grows poorly on mucin glycoproteins, we demonstrate a clear ability of R. torques to liberate products from mucins, making them accessible to B. thetaiotaomicron. This work underscores the diversity of mucin-degrading mechanisms in different bacterial species and the probability that some species are contingent on others for the ability to more fully access mucin-derived nutrients. The ability of R. torques to directly degrade a variety of mucin and mucin glycan structures and unlock released glycans for other species suggests that it is a keystone mucin degrader, which may contribute to its association with IBD.
2024-06-19 | PXD051107 | Pride
Project description:Dr. Clausen's laboratory is interested in the structure, biosynthesis and genetic regulation of glycoconjugates, with a major focus on mucins. This laboratory is studying the glycosylation and secretion process of mucins and biological functions involving mucins. This lab is also interested in receptor modulation mediated by glycosylation or through glycosphingolipids. We have a particular interest in understanding how mucin type O-glycosylation is regulated. Mucin type O-glycosylation is controlled by the ppGalNAc-transferase multigene family. An estimated 23 iso-forms belong to this family, so the specific involvement of each individual iso-form in any given organ seems complex to understand. An initial attempt to comprehend how this multigene family regulates mucin type O-glycosylation, is to get insight into which iso-forms are expressed in different organs and cell types. For this reason we have generated monoclonal antibodies towards 7 iso-forms, and the list of ppGalNAc-T iso-form specific monoclonals is currently growing. We have done some immuno histochemistry on lung using the available monoclonals, but are keen on assessing the number of ppGalNAc-T's expressed in lung as determined this Glyco-array. We have focused on lung because a number of ppGalNAc-T acceptor polypeptides, belonging to the mucin gene family, are expressed in this organ.
2010-11-30 | GSE25712 | GEO
Project description:Mucin domains are densely O-glycosylated modular protein domains found in a wide variety of cell surface and secreted proteins. Mucin-domain glycoproteins are key players in a host of human diseases, especially cancer, but the scope of the mucinome remains poorly defined. Recently, we characterized a bacterial mucinase, StcE, and demonstrated that an inactive point mutant retains binding selectivity for mucins. In this work, we leveraged inactive StcE to selectively enrich and identify mucins from complex samples like cell lysate and crude ovarian cancer patient ascites fluid. Our enrichment strategy was further aided by an algorithm to assign confidence to mucin-domain glycoprotein identifications. This mucinomics platform facilitated detection of hundreds of glycopeptides from mucin domains and highly overlapping populations of mucin-domain glycoproteins from ovarian cancer patients. Ultimately, we demonstrate our mucinomics approach can reveal key molecular signatures of cancer from in vitro and ex vivo sources.
2022-06-29 | PXD024995 | Pride
Project description:The major focus of Dr. Argueso's research is to characterize the carbohydrate portion of the different mucins expressed by the ocular surface epithelia as well as the enzymes involved with their synthesis, and to determine whether the alteration of mucin glycosylation is associated with ocular surface disease.
2011-03-02 | GSE27593 | GEO
Project description:The major focus of Dr. Argueso's research is to characterize the carbohydrate portion of the different mucins expressed by the ocular surface epithelia as well as the enzymes involved with their synthesis, and to determine whether the alteration of mucin glycosylation is associated with ocular surface disease. Highly glycosylated mucins on the ocular surface (cornea and conjunctiva) are the first line of defense of the eye against injury and infection. Changes in O-glycosylation of mucins may cause ocular surface disorders, such as dry eye. Gene expression patterns in the conjunctival epithelium of three normal subjects were analyzed. The three subjects have the same ABO-blood-group. For each donor, conjunctival cells were obtained by impression cytology. Conjunctival impression cytology was performed on each eye two times with a one-week interval. Conjunctival cells obtained from each individual were pooled and the RNA isolated. All three samples were hybridized to the custom designed CFG GLYCOv2 glycogene array.
2011-03-02 | E-GEOD-27593 | biostudies-arrayexpress
Project description:Dr. Clausen's laboratory is interested in the structure, biosynthesis and genetic regulation of glycoconjugates, with a major focus on mucins. This laboratory is studying the glycosylation and secretion process of mucins and biological functions involving mucins. This lab is also interested in receptor modulation mediated by glycosylation or through glycosphingolipids. RNA samples from two human pancreatic cell lines. The relevance of the variable expression levels of isoforms belonging to the polypeptide GalNAc-transferase gene-family is still a puzzle to us. The polypeptide GalNAc-transferase gene family is estimated to contain 24 gene-members all participating in the initiation of mucin-type O-glycosylation. It has become apparent that each of these individual isoforms have different tissue distribution profiles and kinetic capabilities. Mucin-type O-glycosylation is thus controlled, and dependent upon the repetoir of expressed GalNAc-transferases in any given organ and cell type at any given time. We have been trying to contribute to the understanding of the ordered process controlling mucin-type O-glycosylation in both normal and malignant models, and are currently investigating a pancreatic cell line model in the lab. The pancreatic tumor cell line ASPC-1 has been found to possess low metastatic potential in mouse models, in contrast to the pancreatic tumor cell line Suit-T2 possessing high metastatic potential. Immunohistochemical analysis of both cell lines, ASPC-1 and Suit-T2, using our monoclonal antibodies to 7 isoforms has revealed great differences in the expression profile of these 7 isoforms in theses two cell lines, and for instance GalNAc-T3 has been found to be highly expressed in Suit-T2 but completely lacking in ASPC-1. Two cell lines: ASPC-1 and Suit-T2 are analyzed with 3 independent replicate prepared for each cell line.
2010-12-11 | E-GEOD-26011 | biostudies-arrayexpress
Project description:Mucins are functionally implicated in a range of human pathologies, including cystic fibrosis, influenza, bacterial endocarditis, gut dysbiosis, and cancer. These observations have motivated the study of mucin biosynthesis as well as development of strategies for inhibition of mucin glycosylation. Mammalian pathways for mucin catabolism, however, have remained underexplored. The canonical view, derived from analysis of N-glycoconjugates in human lysosomal storage disorders, is that proteolysis and glycan degradation occur largely independently. Here, we challenge this view by providing genetic and biochemical evidence supporting mammalian proteolysis of heavily O-glycosylated mucin domains, without prior deglycosylation. Using activity screening coupled with mass spectrometry we ascribed mucin-degrading activity in murine liver to the lysosomal protease cathepsin D. Knockout of cathepsin D in a murine model of the human lysosomal storage disorder neuronal ceroid lipofuscinosis resulted in accumulation of mucins in liver-resident macrophages. Our findings suggest that mucin-degrading activity is not limited to the bacterial kingdom and is a component of glycoprotein catabolism in mammalian tissues.
2022-09-03 | PXD027616 | Pride
Project description:Mucins and glycoproteins with mucin-like regions contain densely O-glycosylated domains often found in tandem repeat (TR) sequences. These O-glycodomains have traditionally been difficult to characterize because of resistance to proteolytic digestion, and knowledge of positions of O-glycans is particularly limited for these regions. Mucin O-glycodomains are believed to contain important binding cues for endogenous lectin receptors and the microbiota, and it is important to develop strategies to characterize and produce these abundant molecules. Here, we took advantage of our recently developed glycoengineered cell-based platform for display and production of mucin TR reporters with custom designed O-glycosylation to characterize O-glycodomains derived from mucins and mucin-like glycoproteins. We combined intact mass and bottom-up site-specific analysis for mapping O-glycosites in MUC2, MUC20, MUC21, PSGL-1, and Syndecan-3. We found that all the potential Ser/Thr positions in these O-glycodomains were O-glycosylated when expressed in HEK293 SimpleCells (Tn-glycoform). Interestingly, while all the sites in TRs derived from secreted mucins were almost fully occupied, positions in TRs from a subset of transmembrane mucins were less efficiently processed. We further used the mucin TR reporters to characterize cleavage sites of the StcE and BT4244 glycoproteases, revealing a more restricted substrate specificities than reported. Finally, we used these for bottom-up analysis of isolated ovine submaxillary mucin (OSM) and identified the gene. The study provides insight into O-glycosylation of mucins and mucin-like domains and the strategies developed open up for wider analysis of native mucins.
2022-05-20 | PXD029885 | Pride