Extracellular adenosine-5'-triphosphate (ATP), released from damaged cells or coreleased as a cotransmitter from synaptic vesicles, acts on its plasma membrane receptors termed purinergic. Purinergic P2X receptors are ATP-gated cation channels. To date seven P2X isoforms designated P2X1-7 have been cloned that are organized as trimeric homomers or heteromers. All P2X subunits share a similar structure consisting of a large extracellular loop, two transmembrane domains and intracellular N- and C- termini. An additional structural feature is conserved aminoacids, these include ten conserved cysteine residues in the extracellular loop. All ectodomain cysteines form disulfide bonds which are organized in two areas: three disulfide bridges are localized in the N-termini half and two in the C-termini half at P2X receptor. ATP binding pocket is apparently localized between two neighbouring subunits. The aim of this Diploma Thesis was to examine the relevance of ectodomain cysteine residue and/or disulfide bonds for the expression, function and ATP binding properties of the P2X receptor. All ten, one by one, ectodomain cysteines were substituted by alanines and ATP-induced currents was recorded in HEK293 cells expressing wild-type P2X4 receptor and its mutants. Low responsible or nonfunctional mutants...
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:284921 |
| Date | January 2010 |
| Creators | Tvrdoňová, Vendula |
| Contributors | Teisinger, Jan, Zemková, Hana |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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