Over the course of the semester, our trainees are reviewing webinars in their given fields and preparing abstracts to help colleagues outside their discipline make an informed choice about watching them. As our program bridges diverse disciplines, these abstracts are beneficial for our own group in helping one another gain key knowledge in each other’s fields. We are happy to share these here for anyone else who may find them helpful.
Laura Clarke, Ph.D
April 11, 2019
Fralin Biomedical Research Institute
This seminar gives an overview of Dr. Clarke’s postdoctoral research at Stanford University, where she was involved in the publication of several high profile papers that help to elucidate the mechanism of astrocyte involvement in healthy neuronal function. I enjoyed viewing this seminar, and I think that Dr. Clarke explains her complex studies in a way that is easy for other scientists to understand.
The seminar begins with an overview of the function of multiple glial cell types: oligodendrocytes, microglia, and astrocytes. Glial cells make up approximately half of the cells in the brain and are highly interactive, but they are also known to contribute to disease pathogenesis. She moves on to focus on astrocytes, which are the most abundant cell type in the brain. Her research found that astrocytes are involved in synapse regulation by the phagocytic pruning of excess excitatory synapses. This action is activity dependent, where more active synapses are less likely to be pruned. These effects were seen in both the developing visual pathway as well as the hippocampus.
In my opinion, the most interesting portion of this talk centered around her optimization of new techniques to study adult rodent brains. Studying adult animals can be advantageous because it allows circuits to develop normally and more closely approximate the normal aging process. However, adult cells are harder to isolate due to a thickening of the extracellular matrix. Dr. Clarke developed new tools for studying astrocytes which involved the injection of an AAV virus to conditionally knockdown astrocytes, or a conditional knockout model that is induced via injection of Tamoxifen. These techniques offer a new way for all who are interested in astrocytes to extend their mouse studies, and are not just limited to her specific research interests.