Bipotence
In biology, bipotency describes the possibility (potency) of cells, tissues or organs to take one of two (prefix bi-) differentiations or development paths. Bipotent (stem) cell lines can e.g. B. differentiate into one of two differentiated cell types. Correspondingly, there are also multipotent , pluripotent and totipotent cells.
The term is often used in connection with the development of the gonads and germ cells. The anatomical basis of the male and female gonads is the same in vertebrates (such as humans); Wolff's and Müller's corridors are initially created in the same way in both sexes. The differentiation usually takes place via the expression of the sex chromosome, mediated via the protein TDF and is subsequently controlled hormonally. In rare cases there is a deviating development so that the anatomical and hormonal sex does not match the genetic, which is defined by the presence of the Y chromosome, very rarely gonads of both sexes are formed next to each other or both partially (true hermaphroditism , see also intersexuality ).
The primordial germ cells themselves are also bipotent. In mice and bony fish it has also been experimentally proven that the same cells can develop into egg cells and sperm.
literature
- Olaf Hiort, Paul-Martin Holterhus: The molecular basis of male sexual differentiation. In: European Journal of Endocrinology. 142, 2000, pp. 101-110. PMID 10664515 (open access)
Individual evidence
- ^ Ian R. Adams, Anne McLaren: Sexually dimorphic development of mouse primordial germ cells: switching from oogenesis to spermatogenesis. In: Development. 129 (5), 2002, pp. 1155-1164.
- ↑ Tomoyuki Okutsu, Kensuke Suzuki, Yutaka Takeuchi, Toshio Takeuchi, Goro Yoshizaki: Testicular germ cells can colonize sexually undifferentiated embryonic gonad and produce functional eggs in fish. In: PNAS Proceedings of the National Academy of Sciences USA. vol. 103 no. 8, 2006, pp. 2725-2729.