MEMPHIS, Tenn., Oct. 10 /PRNewswire/ -- A gene called Six2 plays a critical role in the development of the kidney by keeping a population of "parent" stem cells constantly available to produce the differentiated cells that give rise to specialized parts of the organ, according to investigators at St. Jude Children's Research Hospital. Differentiation is the process by which a progenitor (unspecialized) cell develops characteristics specific to its job in the body. This provides vital clues into the development of other organs.
The kidney stem cells, called mesenchymal blastemal cells, are the source of cells triggered by chemical signals to differentiate into nephrons -- the structures in the kidney that cleanse the blood of waste. The St. Jude team showed that Six2 works by preventing some of the precursor cells from responding to these signals. That ensures that there will be a continual source of undifferentiated stem cells available to maintain the growth of the kidney.
"Our work shows that Six2 is critical to preventing the developing kidney from running out of stem cells and collapsing into a mass of underdeveloped tissue," said Guillermo Oliver, Ph.D., a member of the St. Jude Department of Genetics and Tumor Cell Biology. Oliver is senior author of a report on this finding that appears in the online issue of The EMBO Journal.
"Our discovery of the role of Six2 in the developing kidney suggests that a similar mechanism exists in other developing organs," noted Michelle Self, the doctoral student in Oliver's laboratory who did most of the work on this project.
The researchers also found that Six2 works by suppressing a cascade of genetic interactions normally triggered by a gene called Wnt4, which usually drives the normal development of kidneys.
The other authors of this study include Oleg Lagutin, Beth Bowling, Jaime Hendrix (St. Jude) and Yi Cai and Gregory Dressler (University of Michigan).
This work was supported in part by the National Institutes of Health, a Cancer Center Support grant, ALSAC and the Polycystic Kidney Disease Foundation.
St. Jude Children's Research Hospital
St. Jude Children's Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tennessee, St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fund-raising organization. For more information, please visit www.stjude.org.
St. Jude Children's Research HospitalCONTACT: Bonnie Kourvelas, Public Relations, +1-901-495-4815, orbonnie.kourvelas@stjude.org, or Marc Kusinitz, Ph.D., ScientificCommunications, +1-901-495-5020, or marc.kusinitz@stjude.org, both of St.Jude Children's Research Hospital
Web site: http://www.stjude.org//