Convergent evolution of immunological tolerance in female and male pregnancy
ACRONYM
Converge preg
Title
Convergent evolution of immunological tolerance in female and male pregnancy
General information
Why males and females exist and how sex roles have evolved belong to the most controversial issues in evolutionary biology. To address these questions, the detailed examination of parental investment and the resulting sex-specific morphology need to be examined in systems with differing parental investment solutions. In the animal kingdom, various strategies exist how parents allocate their resources into the future generation. This can range from a mere investment into the production of gametes (eggs and sperm) to complex mechanisms aiming to support the offspring after birth. One form of costly parental investment is viviparity, which has evolved multiple times and can be found in most vertebrate groups. The evolution of mammalian viviparity, i.e. pregnancy and placentation, required specific morphological reorganizations in the sex bearing the young. In addition to morphological adaptations, major changes in the organization and the activity of the immune system were indispensibly associated with pregnancy and placentation. Only if the embryo is immunologically tolerated, a successful pregnancy is permitted. As opposed to mammals, the processes that accompanied the evolution of viviparity in other vertebrates remain severely understudied. To grasp the convergent evolution of parental investment, to find the ultimate driving forces for the evolution of viviparity and to investigate whether viviparity uses similar mechanistic, i.e. genetic, solutions across the animal kingdom, an in depth comparative investigation of parental investment and its concomitant adaptations in non-mammal model systems is vital.Here, I propose to analyze mating system evolution in the most species-rich group of vertebrates, teleost fishes, by studying the evolution of pregnancy and the underlying adaptations in the immunological tolerance in a teleost taxa that displays an extreme form of paternal investment. I will study the sex-role reversed syngnathid fishes featuring unique male pregnancy. Using this enigmatic model system, I aim to address how male pregnancy co-evolved with adaptive immune system re-arrangements. In an experimental approach, I will investigate whether or not male pregnancy limits self-non-self recognition. The use of comparative genomics and transcriptomics in Syngnathiformes that display a range of sex roles from conventional to reversed (syngnathids) will provide the genetic basis of trait loss and gain required for male pregnancy, and will highlight which genes with different original functions were recruited (gene co-option), and which were newly established during the evolution of parental investment. Due to similar selective forces, I expect a similar set of genes to mediate female and male pregnancy, suggesting convergent evolution of pregnancy.
Start
January, 2018
End
October, 2021
Funding (total)
401000
Funding (GEOMAR)
-
Funding body / Programme
-
DFG
/
Coordination
Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR), Germany
Contact