CHAMPAIGN, Ill., April 24 Flatworms aren't as well known as other animals used in research but U.S. scientists say they are ideal subjects for the study of germ cells.University of Illinois developmental biology Professor Phillip Newmark and colleagues studying the planarian Schmidtea mediterranea have made a few discoveries related to genes called nanos, which were previously known to play a critical role in germ cell development in several other model organisms.Unlike fruit flies and nematodes, planarians don't generally express nanos or produce germ cells until several days after hatching. That delayed initiation of germ cell growth is common to mammals and a number of other animals.Graduate student Yuying Wang and other team members have shown blocking nanos expression by means of RNA interference immediately after the planarians hatch prevents the emergence and development of germ cells. Blocking nanos in mature adults causes their ovaries and testes to disappear."This is the first time nanos gene function has been studied in a non-traditional model organism," Newmark said. "This is important because planarians, like mammals, seem to make their germ cells by an inductive mechanism." The study is detailed in the Proceedings of the National Academy of Sciences.Copyright 2007 by UPI
