Allosteric Inhibition of a Vesicular Glutamate Transporter by an Isoform-Specific Antibody
| Autor: | Robert M. Stroud, Fei Li, Jacob Eriksen, Robert H. Edwards |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Gene isoform
Biochemistry & Molecular Biology Allosteric regulation Glutamic Acid Neurotransmission Medical Biochemistry and Metabolomics Biochemistry Synaptic vesicle Article Epitope Antibodies Xenopus laevis Epitopes Medicinal and Biomolecular Chemistry Chlorides Allosteric Regulation Monoclonal Vesicular Glutamate Transport Proteins Extracellular Animals Humans Protein Isoforms Chemistry Glutamate receptor Neurosciences Antibodies Monoclonal Transporter Cell biology Brain Disorders HEK293 Cells Vesicular Glutamate Transport Protein 1 Vesicular Glutamate Transport Protein 2 Biochemistry and Cell Biology Biotechnology |
| Zdroj: | Biochemistry, vol 60, iss 32 Biochemistry |
| Popis: | The role of glutamate in excitatory neurotransmission depends on its transport into synaptic vesicles by the vesicular glutamate transporters (VGLUTs). The three VGLUT isoforms exhibit a complementary distribution in the nervous system and the knockout of each produces severe, pleiotropic neurological effects. However, the available pharmacology lacks sensitivity and specificity, limiting the analysis of both transport mechanism and physiological role. To develop new molecular probes for the VGLUTs, we raised six mouse monoclonal antibodies to VGLUT2. All six bind to a structured region of VGLUT2, five to the luminal face and one to the cytosolic. Two are specific to VGLUT2 whereas the other four bind to both VGLUT1 and 2; none detect VGLUT3. Antibody 8E11 recognizes an epitope spanning the three extracellular loops in the C-domain that explains the recognition of both VGLUT1 and 2 but not VGLUT3. 8E11 also inhibits both glutamate transport and the VGLUT-associated chloride conductance. Since the antibody binds outside the substrate recognition site, it acts allosterically to inhibit function presumably by restricting conformational changes. The isoform specificity also shows that allosteric inhibition provides a mechanism to distinguish between closely related transporters. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|