There are few of them animals are stranger than marine fish, a species for which it is very difficult to find an assistant captain, that when a male and a female merge underwater, males merge with their females for life. After the merger, they both have one respiratory and digestive system.
Scientists have now found that marine marine fish carry out this sexual parasitism by losing a major part of their immune system, allowing two bodies to become one without tissue rejection. (Remember the symbiote of Jadzia Dax from Nine nine spaces?)
All vertebrates, including humans, have two types of immune systems. The first is an innate system that responds quickly to attacks by microscopic intruders using a variety of chemicals, such as physical barriers to the mucous membranes, such as hair and skin, and disease-carrying cells called macrophages. The second line of defense is an adaptive system that produces both “killer”; T cells to attack the pathogen and antibodies specifically made to fight specific bacteria or viruses. Both systems work together to fight infections and prevent disease.
But in a study published in the magazine on Thursday Science, researchers from the Max Planck Institute in Germany and the University of Washington found that many devil species (more than 300) have lost the genes that control their adaptive immune system over time, meaning they are unable to produce antibodies and do not have them. T cells.
“Marine marine fish trade in their faculties of immunity, which we believe are necessary for this reproductive behavior,” said Thomas Boehm, a professor at the Institute’s Department of Immunobiology and Epigenetics in Freiburg, Germany.
To reach this conclusion, Boehm and his colleagues have spent the past six years performing genetic sampling of tissue samples from marine animals taken from around the world. They tried to catch them using deep-sea trawls that collect specimens 1,000 feet below the surface, but because marine marine fish are rare and difficult to reach, they have not been able to collect any live specimens. Thus, to obtain enough tissue for their genetic analysis, researchers instead cut out museum collections and other laboratories that contained preserved preserved marinated marine fish, some of which were decades old.
There are several breeding methods in the redfish family. Some species of females merge with a single male; others merge with several males; and another group has only a temporary fusion. After shredding 31 tissues from samples of 10 species, the team performed genetic testing and found that the species that temporarily fused with their friends lacked the genes responsible for antibody maturation. Species that develop persistent attachment to their buddies have also lost additional genes responsible for the assembly of T cell receptors and antibody genes that underlie the innate immune system in all vertebrates.
“It was intuitive to think that a certain genetic craving made it happen,” says Boehm about the unusual immune system of sea fish species. “This is the first evidence that these animals are unable to give up part of themselves and allow these couplings to take place.”