IBN: 9630813 PI: Sueoka The nervous system of higher organisms consists of neurons and glial cells; the function of glial cells is to help neurons. These two cell types are known to come from common, embryonic precursor cells (neural stem cells). The differentiation of neural stem cells into neurons and glial cells, therefore, is the critical process for the development of the nervous system. In spite of the fundamental importance of stem cell differentiation, the mechanisms underlying this differentiation (identification of the genes involved and the functions of these genes) are not well understood. We have isolated and characterized in detail a rat stem cell line that differentiates into neurons and glial cells in culture. This system is ideal for molecular studies on the neuronal-glial differentiation of neural stem cells. Using this system, we have isolated several candidate gene fragments that may be critically important for neural stem cell differentiation. Using these fragments, we plan to isolate and characterize the genes and determine their functions in the development of the nervous system. Among several gene fragments that are potentially important, there is a particularly promising gene fragment which we are going to study first. The gene corresponding to this fragment is expressed in the neuronal cell line but not in the stem cell line. This fragment has a region with almost identical DNA sequence to a control region of a Drosophila gene that is essential for the development of the nervous system.
