The mechanisms by which polarized neural stem cells divide to produce various progenitor, neuronal, and glial cell types at precise times during development remain among the most compelling mysteries in biology and medicine. How these cells split to produce two daughters with symmetric or asymmetric fates, while still maintaining polarity and epithelial structure, remains unclear despite much progress. Cytokinesis, the actual partitioning of cytoplasmic and membrane components, has rarely been directly studied in neural stem cells. The objective of this particular application is to directly study and perturb cytokinesis in mammalian neural stem cells, both in vivo and in vitro. The central hypothesis is that cytokinesis mechanisms differ between early proliferative and later neurogenic division phases, contributing actively to the generation of a cerebral cortex of the proper area and layer structure. We will test this hypothesis through three Specific Aims: 1) characterize and perturb spatial and temporal parameters of cytokinesis in cortical neural progenitors at different stages of development, 2) correlate midbody inheritance patterns with symmetric and asymmetric fates, and test the fate consequences of experimentally increasing midbody retention, and 3) elucidate phenotypes produced when cytokinesis is specifically disrupted during early or late stages of development. Our long-term goal is to elucidate how specific alterations in cell division mechanisms in different progenitor types during development can lead to variations in brain size and structure, malformations, or other disorders. The contributions of the proposed research are expected to be a foundation of innovative approaches and tools for studying cytokinesis in normal and abnormal brain development, and a more detailed understanding of how cytokinetic structures partition apical components in neural progenitors. These contributions will be significant because they may uncover novel mechanisms that contribute to differential fate determinant segregation for neural stem cell renewal or neurogenesis, and make predictions for human brain phenotypes that may arise from global or localized defects in cytokinesis.

Public Health Relevance

The proposed research is relevant to public health because abnormalities in neural stem cell divisions in the developing brain may result in brain malformations or more subtle abnormalities leading to epilepsy, autism, or other neural disorders. A better understanding of the basic mechanisms of these divisions will elucidate the causes of these disorders, and inform diagnoses and the potential utility of neural stem cells for neurological treatments. The outcomes will be relevant to the mission of NINDS to reduce the burden of neurological disease and trauma, and will impact many areas of biology and translational medicine.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS076640-01A1
Application #
8500876
Study Section
Neurogenesis and Cell Fate Study Section (NCF)
Program Officer
Riddle, Robert D
Project Start
2013-04-01
Project End
2018-03-31
Budget Start
2013-04-01
Budget End
2014-03-31
Support Year
1
Fiscal Year
2013
Total Cost
$345,625
Indirect Cost
$126,875
Name
University of Virginia
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
065391526
City
Charlottesville
State
VA
Country
United States
Zip Code
22904