SPUR 2021: Establishing the effect of experience dependent plasticity on dopaminergic signaling in the olfactory bulb

Background

Dopamine is a powerful neurotransmitter capable of modulating information processing throughout the brain. There is a high density of local dopaminergic interneurons and receptors in the olfactory bulb. Pharmacological manipulation of dopamine release in vivo alters the ability for mice to discriminate odorants. Likewise, decreases in dopaminergic tone and a loss of smell are associated with numerous diseases, such as Parkinson's and Alzheimer's disease. To understand dopamine's role in shaping neural circuit activity, this project will investigate how dopamine release and subsequent circuit activity changes as a function of experience.

Student Role

For this project, a talented student will run an odor-enrichment paradigm on mice to assess how dopamine signaling in the brain alters as a function of prior odor experiences. They will determine if experience alters tyrosine hydroxylase (TH) expression, the rate-limiting enzyme necessary for dopamine synthesis. They will also learn how changes in TH expression relate to endogenous patterns of dopamine transmission. Lastly, they will determine how experience-dependent changes in dopamine signaling relate to the rewiring of neuronal circuits. To this end, students will test if experience alters the expression of dopamine receptor subtypes on different populations of neurons in the olfactory bulb circuit. This will shed light on how dopamine modulates neural circuit function as a function of experience.

Student Learning Outcomes & Benefits

With these experiences, this student will not only gain a broad understanding of fundamental neuroscience; they will gain training to some of the most important experimental techniques currently used in neuroscience research. This student will learn how to conduct a mouse behavioral paradigm, perform histology and immunohistochemistry, and participate in cutting-edge in vivo imaging experiments. In addition, this student will also gain experience in analyzing imaging data, science writing, and presenting. It is expected that the student will have the opportunity to present the results of their work at at least one national research conference.

Remote Contingency Plan

The lab is well-prepared to mentor a SPUR student remotely should this contingency arise. In this case, the work would mainly involve learning data analysis methods - specifically, analysis of data from in vivo optical imaging experiments, in which neural activity is reported as changes in fluorescence over time; or of behavioral data, in which an animal's performance in a behavioral task is analyzed. In addition, the student can participate in experiments virtually, in which the postdoc will be collecting imaging or behavioral data and the student can be virtually present in real-time through screen-sharing applications. The student would also have the opportunity to learn Matlab programming to write their own data analysis code. Given this contingency, some interest in image processing and quantitative methods such as signal processing will be helpful.

Matt Wachowiak
Professor

Neurobiology & Anatomy
School of Medicine

I have been a hands-on mentor to undergraduate researchers in my laboratory for nearly 20 years, and I interact closely with each student to ensure that they are productive in meeting research goals, and also in moving towards their longer-term career goals. The student will work closely with a senior postdoctoral researcher in the lab, who will provide day-to-day direction on the research project. The three of us will meet weekly to discuss progress, and I also talk with the student one-on-one at the beginning of the summer to talk about their career goals and expectations for the experience, as well as discuss my lab's expectations. Students will participate in weekly lab meetings and be expected to present at one lab meeting before the end of their research experience. If they make sufficient progress on the project over the summer, the student will be invited to attend a national conference that covers their area of study (i.e., Society for Neuroscience, Association for Chemoreception Sciences, or BRAIN Initiative Investigators' annual meeting).

In the past several years, I have used this model to mentor undergraduates through the UROP program and also the NARI Summer Internship program. These have led to co-authorships on published papers and presentations at national meetings. This past summer, a student won the award for Best Undergraduate Research at the International Symposium on Olfaction and Taste, based on her work as a UROP researcher in my laboratory.