Molecular Basis of Synaptic Transmission
Synaptic transmission is an important cellular event underlying development, learning, memory, and other functions of the brain. Neurotransmitter receptors, transporters, and ion channels mediate synaptic communication, and their dysfunction is frequently implicated in neurological and psychiatric disorders.
Our research group is pursuing molecular mechanisms of signal transduction with a specific focus on the synaptic communication, signaling, and plasticity at excitatory and inhibitory synapses. Synaptic plasticity is a process whereby certain synapses are strengthened and others are weakened during active learning and memory.
In many cases, neuroreceptors/ion channels form complexes and interact with scaffold proteins and signaling molecules to localize the specific site of synapses and to transfer information. Receptor functions are allosterically modulated by interacting proteins that regulate synaptic plasticity. We are interested in understanding the fundamental roles of neuroreceptors and their interacting proteins in this process.
Current areas of interest within the lab include the following:
(1) dissecting the signaling networks based on protein-protein interactions that are required for synaptic signal transduction in the mammalian brain including humans
(2) elucidating the structure and function of signaling complexes
(3) developing new therapeutic compounds and antibodies targeting novel binding sites based on the determined structures
We use a variety of structural, biophysical, and electrophysiological techniques including single particle cryo-electron microscopy (cryo-EM), X-ray crystallography, protein biochemistry, surface plasmon resonance (SPR), mass spectroscopy, and electrophysiology to characterize the signaling complexes involved in synaptic function.
Postdoc and student positions available
Positions available for postdoctoral research scientists and students. To apply, please send a cover letter describing research interests, a CV, and contact information for three references to Nami Tajima at email@example.com.
Awards and Honors
- Chou T*, Tajima N*, Romero-Hernandez A, Furukawa H.Structural basis of functional transitions in mammalian NMDA receptors. Cell 2020 Jul 23;182(2):357-371. doi: 10.1016/j.cell.2020.05.052 * These authors contributed equally to this work
- Tajima N, Karakas E, Grant T, Simorowski N, Diaz-Avalos R, Grigorieff N and Furukawa H. Activation of NMDA receptors and the mechanism of inhibition by ifenprodil. Nature 2016 Jun;534:63-68.
- Jespersen A*, Tajima N*, Fernandez-Cuervo G, Garnier-Amblard EC, and Furukawa H. Structural Insights into Competitive Antagonism in NMDA Receptors. Neuron 2014 Jan;81(2):366-378. * These authors contributed equally to this work
- Hansen KB, Tajima N, Risgaard R, Perszyk RE, Jørgensen L, Vance KM, Ogden KK, Clausen RP, Furukawa H, and Traynelis SF. Structural determinants of agonist efficacy at the glutamate binding site of N-methyl-D-aspartate receptors. Mol Pharmacol. 2013 Jul;84(1):114-27.
- Tajima N, Kawai F, Park SY, and Tame JR. A novel intein-like autoproteolytic mechanism in autotransporter proteins. J Mol Biol. 2010 Oct;402(4):645-56.
- Nishimura K, Tajima N, Yoon YH, Park SY, and Tame JR. Autotransporter passenger proteins: virulence factors with common structural themes. J Mol Med. 2010 May;88(5):451-8.