Receptors for the neurotransmitter glutamate in our brain come in several shapes and sizes.
Learning and Memory
Layers of Complexity
Exploring the Structure
This structure (PDB entry 4u5c) shows how things can go wrong. Some cone snails make a small protein toxin that they use to paralyze their prey. It binds in the middle of the glutamate-binding portion of the receptor, corrupting its action. To explore this structure in more detail, click on the image for an interactive JSmol. As you look at this structure, notice that there is a mismatch of symmetry between the different parts: the ion channel forms a typical four-fold structure, but the glutamate-binding portions are two side-by-side dimers.
Topics for Further Discussion
- Ionotropic glutamate receptors are quite flexible--as you look at these structures, notice the many different arrangements of the transmembrane domains relative to the glutamate-binding domains.
- These structures are all missing portions of the receptors, which are not observed because they are so flexible. You can use the Protein Feature View to determine which portions of the protein chain are included in the structure entries.
July 2019, David Goodselldoi:10.2210/rcsb_pdb/mom_2019_7