Germline stem cells are immature cells in the reproductive system that can proliferate and mature into sperm and eggs. While it is has been appreciated that these stem cells exist in a microenvironment attached niche cells, it has not been well understood how these two cell types communicate.
In their latest study, the results of which were published in the Jan. 26, 2005, issue of the journal Current Biology, the Duke team reported that regulatory genes from niche cells instruct genes in stem cells to determine the future path of the stem cells. Both niche and stem cells possess genes which produce proteins that act as a series of "on-off" switches for stem cell division, the researchers said. The research was supported by the National Institutes of Health.
Over-proliferation of stem cells is one of the leading causes of cancer, while reduced stem cell production is implicated in such disorders as infertility, anemia and immune system deficiencies.
It is important to understanding how stem cells receive their cues to differentiate, the researchers continued, because any potential future clinical application of stem cells cannot focus on them alone, but must also take into account the role of niche cells.
For their experiments, researchers led by Duke cell biologist Haifan Lin, Ph.D. studied germline stem cells from the ovaries of the common fruit fly Drosophila. They analyzed the expression of specific genes as the germline stem cells either created additional copies of themselves or differentiated into another cell type known as a cystoblast, which event
Contact: Richard Merritt
Duke University Medical Center