Embroys Development 'Pause' For Up To A Month

Scientists have found a way to pause the development of early mouse embryos for up to a month in the lab – and later resume normal growth – a finding with potential implications for assisted reproduction, aging and even cancer. The research involved experiments with pre-implantation mouse embryos, called blastocysts. Researchers from University of California, San Francisco in the US found that drugs that inhibit the activity of a master regulation of cell growth called in mTOR can put these early embryos into a stable and reversible state of suspended animation. Normally, blastocysts only a last day or two, max, in the lab. But blastocysts treated with mTOR inhibitors could survive up to four weeks. Researchers showed that paused embryos may quickly resume normal growth when mTOR inhibiters were removed, and developed into healthy mice if implanted back into a recipient mother. The drugs appear to act by reducing gene activity across much of the genome. The researchers believe that it should be possible to extend the suspended animation for much longer than the 30 days observed in the present study.