SEATTLE — For the first time, researchers at Fred Hutchinson Cancer Research Center have identified and isolated adult mammary stem cells in mice. Long-term implications of this research may include the use of such cells to regenerate breast tissu…
In a study that combines state-of-the-art biological imaging with gene expression analysis, scientists at the California Institute of Technology have uncovered a fundamental insight into the way embryonic cells and tissue move about to form key structures along the vertebrate axis. The study, which could lead to a better understanding of human development, takes advantage of the accessibility of chick embryos to embryonic manipulation. The study enters on segments known as somites, which form along either side of the future spinal cord of an embryo. Somites give rise to mature structures such as ribs, individual vertebrae, and even skin. The key role of somite segmentation in the patterning of the nervous system and the vertebral column has been long known. But the question of precisely how an individual somite buds off from a block of tissue in a pattern that is repeated all along the animal’s torso, from head to tail, is poorly understood.