In the scientific community is still ongoing debate about whether the egg can be generated throughout life. More than half a century, most scientists held the view that the eggs can not be restored. A woman is born with a certain number of oocytes that are gradually consumed during the life until menopause. But the recent discovery of scientists strongly shattered that theory.
First, rodents, and then women scientists found oogonia stem cells capable of producing oocytes even after menopause in adulthood. If it were possible to find a tool that can activate these stem cells, we could solve a lot of reproductive problems, including infertility problem. However, the experiments of Swedish scientists from the University of Gothenburg have dispelled all hopes.
Swedish experts have decided to repeat the experiments with stem oogonia, but made one change. Discoverers of these reproductive cells found them on protein DDX4. Antibodies to this protein allows to "catch" oogonia stem cells from other cells.
The researchers found that this protein is most often found in the cytoplasm and very rarely on the surface of cells. They decided to carry out experiments with modified mice whose germ cells depending on the working genes synthesized various fluorescent proteins. A cell with a gene Ddx4 stood out among the other special painting.
Scientists have found that no cell carrier protein DDX4, that is, having the characteristics of the stem, to a mature oocyte has not evolved. It turns out that the previously discovered stem cells or oogonia are not able to ripen, or represent something else.
Discoverers of reproductive cells, of course, are not left behind. They said that all the subtlety here is the location of the protein DDX4. If it is on the surface, then it is a stem cell, and if the inside, this is nothing like an immature oocyte, no longer able to divide. So that, in their opinion, the Swedish scientists, recheck the result, not just studying those cells. Data from other laboratories confirmed the words of the pioneers of self-healing eggs. However, in any case, the egg derived from reproductive stem cells are not ready for fertilization.
According to the materials Sciencemagic.ru