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Regulatory roles of PAG and CSK in FcɛRI signaling of mast cells
Potůčková, Lucie ; Dráber, Petr (advisor) ; Šebo, Peter (referee) ; Holáň, Vladimír (referee)
8 1 ABSTRACT (EN) This thesis is focused mainly on understanding mechanisms of regulatory roles of C-terminal Src kinase (CSK) and phosphoprotein associated with glycosphingolipid- enriched microdomains (PAG) in the high-affinity IgE receptor (FcɛRI)-mediated signaling of murine mast cells. FcɛRI activation is initiated by aggregation of the receptor by complexes of multivalent antigen with IgE, followed by activation and enhanced activities of protein tyrosine kinases, phosphatases, adaptor proteins and number of other signal transduction molecules. The signaling events result in mast cell degranulation and release of variety of proinflammatory mediators, responsible for initiation of allergy and other inflammatory diseases. Understanding the function of key regulatory molecules controlling FcεRI-mediated mast cell activation, degranulation, and cytokines production could have therapeutic impact. CSK is a major negative regulator of Src family tyrosine kinases (SFKs) that play a critical role in various immunoreceptor signaling events. However, its function in mast cell activation has not been completely understood. Because of its cytoplasmic localization, CSK was assumed to be brought to the vicinity of the plasma membrane- bound SFKs via binding to membrane-bound adaptors and PAG was a major candidate....
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The role of ORMDL proteins in mast cell signaling
Paulenda, Tomáš ; Dráber, Petr (advisor) ; Heneberg, Petr (referee) ; Malý, Petr (referee)
1. Abstract (EN) This thesis is collection of work focused mainly on the understanding of mast cell activation and its regulation by Orm1-like (ORMDL) proteins. ORMDL family is a group of endoplasmic reticulum (ER) membrane resident proteins that are highly conserved amongst mammalian species. ORMDL proteins can be found in diverse range of organisms from plants through fungi to animals. ORMDL proteins were first discovered in yeasts and the interest in these proteins skyrocketed after the discovery that ORMDL3 is associated with childhood onset asthma in genome wide association studies. Following research connected ORMDL3 also with allergic inflammation and inflammatory bowel disease. Since mast cells are mainly known for their role in allergy and allergen induced inflammation, we decided to investigate the role of ORMDL proteins in regulation of mast cell activation and signaling. In our first study we focused on the role of ORMDL3 in mast cell activation via the high affinity IgE receptor 1 (FcεRI). We prepared bone marrow-derived mast cells with decreased (ORMDL3-KD) or increased (ORMDL3-OE) ORMDL3 expression. We showed that ORMDL3 is a negative regulator of mast cell activation events like degranulation, cytokine release and migration, without any effect on calcium mobilization. ORMDL3 was previously...
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The role of ORMDL proteins in mast cell signaling
Paulenda, Tomáš ; Dráber, Petr (advisor) ; Heneberg, Petr (referee) ; Malý, Petr (referee)
1. Abstract (EN) This thesis is collection of work focused mainly on the understanding of mast cell activation and its regulation by Orm1-like (ORMDL) proteins. ORMDL family is a group of endoplasmic reticulum (ER) membrane resident proteins that are highly conserved amongst mammalian species. ORMDL proteins can be found in diverse range of organisms from plants through fungi to animals. ORMDL proteins were first discovered in yeasts and the interest in these proteins skyrocketed after the discovery that ORMDL3 is associated with childhood onset asthma in genome wide association studies. Following research connected ORMDL3 also with allergic inflammation and inflammatory bowel disease. Since mast cells are mainly known for their role in allergy and allergen induced inflammation, we decided to investigate the role of ORMDL proteins in regulation of mast cell activation and signaling. In our first study we focused on the role of ORMDL3 in mast cell activation via the high affinity IgE receptor 1 (FcεRI). We prepared bone marrow-derived mast cells with decreased (ORMDL3-KD) or increased (ORMDL3-OE) ORMDL3 expression. We showed that ORMDL3 is a negative regulator of mast cell activation events like degranulation, cytokine release and migration, without any effect on calcium mobilization. ORMDL3 was previously...
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Regulatory roles of PAG and CSK in FcɛRI signaling of mast cells
Potůčková, Lucie ; Dráber, Petr (advisor) ; Šebo, Peter (referee) ; Holáň, Vladimír (referee)
8 1 ABSTRACT (EN) This thesis is focused mainly on understanding mechanisms of regulatory roles of C-terminal Src kinase (CSK) and phosphoprotein associated with glycosphingolipid- enriched microdomains (PAG) in the high-affinity IgE receptor (FcɛRI)-mediated signaling of murine mast cells. FcɛRI activation is initiated by aggregation of the receptor by complexes of multivalent antigen with IgE, followed by activation and enhanced activities of protein tyrosine kinases, phosphatases, adaptor proteins and number of other signal transduction molecules. The signaling events result in mast cell degranulation and release of variety of proinflammatory mediators, responsible for initiation of allergy and other inflammatory diseases. Understanding the function of key regulatory molecules controlling FcεRI-mediated mast cell activation, degranulation, and cytokines production could have therapeutic impact. CSK is a major negative regulator of Src family tyrosine kinases (SFKs) that play a critical role in various immunoreceptor signaling events. However, its function in mast cell activation has not been completely understood. Because of its cytoplasmic localization, CSK was assumed to be brought to the vicinity of the plasma membrane- bound SFKs via binding to membrane-bound adaptors and PAG was a major candidate....
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New regulatory mechanisms of microtubule nucleation
Černohorská, Markéta ; Dráber, Pavel (advisor) ; Binarová, Pavla (referee) ; Hašek, Jiří (referee)
MT nucleation from γ-tubulin complexes, located at centrosome, is an essential step in the formation of MT cytoskeleton. In mammalian cells, -tubulin is encoded by two genes. We functionally characterized two γ-tubulin proteins and have found that both are functionally equivalent. γ-Tubulin 2 is able to substitute for γ-tubulin 1 in MT nucleation. However, we revealed that unlike TUBG1, TUBG2 expression is downregulated in mouse preimplantation development. Mast cells represent effectors of the allergy reaction. Their activation by antigen induces number of cellular processes such as degranulation, proliferation and cytoskeleton rearrangements. The regulatory mechanisms of MT reorganization during mast cell activation are unknown. We identified new signaling proteins, GIT1 and PIX that interact with - tubulin. Depletion of GIT1 or PIX leads to changes in MT nucleation. GIT1 is phosphorylated on tyrosine and associates with γ-tubulin in a Ca2+ -dependent manner. Our data suggested a novel signaling pathway for MT rearrangement in mast cells where tyrosine kinase-activated GIT1 and βPIX work in concert with Ca2+ signaling to regulate MT nucleation. We tested the capability of GIT1 and PIX to influence -tubulin function in more cell types. We found out that GIT1/βPIX signaling proteins together...
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The cellular elements participating in the inflammatory response
CHMELOVÁ, Veronika
The issue of inflammation is a very complicated and extensive topic, which by far does not just cells that the task of this thesis. It's a proces to helping maintain the internal environment of the organism and its task is cope with external environmental influences, which may mean risk for the organism. Inflammatory cell response is the mechanism which the body defends itself against infections and corrects damaged tissue. But this process can not be understood only as a defensive reaction. Especially with persistent inflammation may evolve a disease state which leads to irreversible tissue damage. In this case, the pathologic response. The theoretical part describes the course of inflammatory reactions and focus on individual blood cells. In this part of thesis, describe their morphological structure, interaction and role in the pathophysiological process. The practical part is devoted to specifics methods which can be used to investigate inflammatory cells. I appreciate their advantages and disadvantages, and describe the principles and practices of these methods. The most basic method is the fabrication and painting the blood smear and microscopic minus differential leukocyte budget. For higher level can be considered Hematology Analyzer, in addition to white blood cells provides a range of information, including platelets and red series. The last method, which the work is concerned with flow cytometry. The huge growth in recent years, the opportunity to investigate a large number of parameters. But this places high demands on the correct interpretation of the data. The last part is concerned with mast cell and problems of its investigations both in terms of hematological and histological methods.
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