T. osimensis stem cells, originally derived from female rat cells, were found in both male and female rat-mouse chimeras.HONDA ET AL., SCI ADV, 3:E1602179, 2017In most mammals, females have two X chromosomes and males have one X and one Y. But both male and female Amami spiny rats (Tokudaia osimensis)—endangered rodents native to a Japanese island—carry just a single X chromosome. In a study published today (May 12) in Science Advances, a research team led by Arata Honda of the University of Miyazaki in Japan used fibroblasts from the tail of a female spiny rat to derive induced pluripotent stem cells (iPSCs). These cells were capable of differentiating into both female and male germ cells in the body of a host organism, a mouse-spiny rat chimera.
“This is a very intriguing paper,” said Oliver Ryder, who is the Director of Conservation Genetics at the San Diego Zoo Institute for Conservation Research and did not participate in the work. Generating “chimeras that can incorporate induced pluripotent stem cells from an endangered species and show indications of producing gametes from the donor cells” has exciting potential as another method of species conservation, he explained.
Location of the island in which T. osimensis residesCARLA SCHAFFER/AAAS AND MIYAZAKI CITY PHOENIX ZOOThe research team cultured fibroblasts from the tail of a female spiny rat, which was released back into the wild. After trying a variety of induction and culture conditions, the authors obtained T. osimensis iPSC lines. They introduced these cells into mouse blastocysts, and then implanted them into surrogate mouse mothers.
The researchers traced the injected iPSCs with a fluorescent marker, and determined that about a quarter of embryos and pups were chimeras. When they examined the adult chimeras, the authors found iPSCs in multiple ...
