Abstract

A central obstacle in stem cell biology is revealing signaling pathways that drive stem cells to mature into differentiated daughter cells or proliferate into more stem cells (self renewal). Some genes that promote self-­‐renewal also promote some forms of cancer. A subpopulation of cells within solid tumors exhibit stem cell-­‐like properties, including resistance to cell death and exhibiting self-­‐renewal. Reviewing published databases of gene expression profiles for glioblastomas and neural stem cells (NSC), we identified genes shared in both populations, including the gene ZSCAN21. Utilizing the constitutively active intracellular domain of the Notch receptor (NICD) as a positive control and an empty vector as a negative control, the sufficiency of ZSCAN21 to promote self-­‐renewal can be monitored using in ovo electroporation of the chick embryonic spinal cord. Immunohistochemistry and comparative anatomical analysis is then used to screen for markers in differentiated neurons (NeuN) and glia (GFAP) as well as markers for progenitor cells (Sox2, Oct4). If ZSCAN21 sufficiently promotes self-­‐renewal, overexpression of the gene should elevate markers for progenitor cells, possibly at the expense of markers for differentiated cells.