Novelty-induced memory boost

Novelty-induced enhancement of memory retention, is now an established phenomenon (Takeuchi et al., Nature, 2016), but the underlying molecular mechanisms remain to be elucidated.

[1] in order to investigate this subject in further detail, we now have the behavioral setup including the hippocampus-dependent object dislocation task and everyday memory task in rats to investigate this subject in further detail. Further, [2] we have an advanced fiber photometry setup, where we are able to detect novelty-induced dopamine release in the hippocampus. That is achieved by using a genetically encoded fluorescent sensor (Nakamoto et al., bioRxiv, 2020) in free-moving rats. Finally, [3] we are trying to identify key proteins critical for novelty-induced enhancement of memory retention in the hippocampal neurons. The theory behind this approach is the synaptic tagging and capture hypothesis (Frey and Morris, Nature, 1997; Okuda et al., European J Neurosci, 2020). Identification of proteins that enhance memory retention will have the potential to reveal new drug targets for treatment of lost memory function.

Rats are the basis for our behavioural experiments. We are using a Lister-hooded TH-Cre transgenic rat strain.
Brain sections are stained with antibodies to confirm that virus has been expressed in the desired brain regions and neurons

We have developed a red-fluorescent dopamine sensor “R-GenGAR-DA1.2” (DA1.2) to detect dopamine release in the hippocampus during novelty experience.
The image series shows a visualization on the response to dopamine by DA1.2, expressed in a rat hippocampal neuron. DA1.2 reduces fluorescence intensity upon application of dopamine, and then returns to the basal level by application of dopamine receptor antagonist (SCH).
This work has been done in collaboration with Dr. Kazuhiro Aoki lab (@ kazuhiroaokilab)

We are using an advanced photometry setup. Using this setup, we can do in-vivo experiments to examine the crosstalk between different  brain regions