Nature & Environment
The Evolution of the Immune System: Ancient Gene Creates Fish-Like Thymus
Catherine Griffin
First Posted: Aug 20, 2014 06:34 AM EDT
Scientists may have just managed to re-activate the expression of an ancient gene that causes animals to develop a fish-like thymus. The findings reveal a bit more about how the immune system evolved over the course of evolution.
One of the core organs of the adaptive immune response in mammals is the thymus, which exists in all vertebrate species. Epithelial cells in the thymus control the maturation of T-cells, which later fight degenerated or infected body cells. More specifically, the gene FOXN1 is responsible for the development of these T-cells in the mammalian thymus.
In this latest study, the researchers activated the evolutionary ancestor of FOXN1, called FOXN4, in the thymic epithelial cells of mice. While FOXN4 is present in all vertebrates, it appears to only play a role in the maturation of immune cells of jawed fish, such as zebra fish. Interestingly, the researchers found that not only T-cells developed in the thymus of the mice, but also B-cells. Mature B-cells are responsible for antibody production and in mammals, usually do not mature in the thymus.
"The simultaneous expression of FOXN4 and FOXN1 in the mouse led to a thymus that showed properties as in fish," said Jeremy Swann, first author of the new report, in a news release.
This suggests that the development and function of thymic tissue was originally initiated by FOXN4. Due to an evolutionary gene duplication, which led to FOXN1, both genes and, eventually only FOXN1, were active in the thymus.
"Our studies suggest a plausible scenario for the transition of a bipotent lymphopoietic tissue to a lymphoid organ supporting primarily T cell development," said Thomas Boehm, one of the researchers. "Here, the recreation and functional analysis of presumed ancestral stages could provide essential insights into the course of such developments."
The findings are published in the journal Cell Reports.
See Now:
NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone
TagsEvolution, Immune System ©2024 ScienceWorldReport.com All rights reserved. Do not reproduce without permission. The window to the world of science news.
More on SCIENCEwr
First Posted: Aug 20, 2014 06:34 AM EDT
Scientists may have just managed to re-activate the expression of an ancient gene that causes animals to develop a fish-like thymus. The findings reveal a bit more about how the immune system evolved over the course of evolution.
One of the core organs of the adaptive immune response in mammals is the thymus, which exists in all vertebrate species. Epithelial cells in the thymus control the maturation of T-cells, which later fight degenerated or infected body cells. More specifically, the gene FOXN1 is responsible for the development of these T-cells in the mammalian thymus.
In this latest study, the researchers activated the evolutionary ancestor of FOXN1, called FOXN4, in the thymic epithelial cells of mice. While FOXN4 is present in all vertebrates, it appears to only play a role in the maturation of immune cells of jawed fish, such as zebra fish. Interestingly, the researchers found that not only T-cells developed in the thymus of the mice, but also B-cells. Mature B-cells are responsible for antibody production and in mammals, usually do not mature in the thymus.
"The simultaneous expression of FOXN4 and FOXN1 in the mouse led to a thymus that showed properties as in fish," said Jeremy Swann, first author of the new report, in a news release.
This suggests that the development and function of thymic tissue was originally initiated by FOXN4. Due to an evolutionary gene duplication, which led to FOXN1, both genes and, eventually only FOXN1, were active in the thymus.
"Our studies suggest a plausible scenario for the transition of a bipotent lymphopoietic tissue to a lymphoid organ supporting primarily T cell development," said Thomas Boehm, one of the researchers. "Here, the recreation and functional analysis of presumed ancestral stages could provide essential insights into the course of such developments."
The findings are published in the journal Cell Reports.
See Now: NASA's Juno Spacecraft's Rendezvous With Jupiter's Mammoth Cyclone