IOS Proposal: Effects of vision loss on astrocyte maturation and oligodendrocyte myelination via BDNF-associated mechanisms in the visual cortex

Emmanuel College, Boston MA

Investigators

Abstract

The purpose of this project is to determine the role of two molecules, known as BDNF and pro-BDNF, that are produced by two distinct populations of cells called astrocytes and oligodendrocytes found in the vision processing area of the brain. The researchers hypothesize that these molecules regulate the development of the circuits that make vision possible. The expression patterns of the regulatory molecules will be determined at different stages of development in normal mice and in mice that show a progressive loss of vision during postnatal development. The expectation is that there will be reduced expression of the molecules in the sightless mice which, in turn, will prevent functional vision circuits from developing. The work has potential to provide a fresh perspective on how vision circuits are formed and organized during development. Undergraduates at three primarily undergraduate liberal arts institutions will receive training in molecular and cellular techniques and modern methods of cell imaging. High-resolution images of fluorescent labeled cells will be archived in an image data bank for use in teaching neuroscience classes for undergraduates and workshops for local high school science students. Normal mice and mice exhibiting vision loss at developmental time points when vision exists, when it is deteriorating, or when it is lost will be used for the proposed studies. The mice have been engineered to express fluorescent biomarkers under the control of cell-specific promoters to enable identification of astrocytes and oligodendrocytes in the brain. Fluorescence activated cell sorting will be used to isolate astrocytes and oligodendrocytes. Brain-derived neurotrophic factor (BDNF) and its precursor (pro-BDNF) mRNA and protein will be measured and visualized using quantitative RT-PCR, ELISA assays, and immunohistochemistry. Image analysis will provide information on changes in astrocyte and oligodendrocyte cell morphology that are predicted to be important in establishing and maintaining vision circuit microenvironments. Data will be made available to other researchers upon request.