Scientists of the Institute of Biomedical Studies of Whitehead and Massachusetts Technological Institute disclosed the mechanism of symmetry from marine stars in the process of development of the embryo. It turned out that the main role is played by the disheveled protein, which creates polarity in the initial cells for the future axis of symmetry. This is reported in the article published in the journal Current Biology.
To determine the complex body formation process, the researchers studied Patiria Miniata starfish. In adulthood, they have a radiation symmetry, and their larvae are bilateral symmetry. The symmetry of the larvae is installed at the stage of egg cells, called oocytes. Disheveled protein is localized on the vegetative or “lower” end of the oocyte (which defines the back end of the embryo) when the cell is prepared to divide into two subsidiaries.
disheveled is associated with a common signal path called WNT, which is found in many living organisms. At sea stars, this path provides the relationship between the initial asymmetry of the oocyte and the polarity of the embryo formed. First, disheveled is evenly distributed across the entire cytoplasm of the nonsense oocyte, but in the process of dividing the proteins are redistributed, accumulating in the largest point from the kernel.