The immune-modulating pregnancy-specific glycoproteins evolve rapidly and their presence correlates with hemochorial placentation in primates

• DOI: 10.1186/s12864-021-07413-8
• Publication Date: 2021-02-20T16:02:26Z
• Authors: Wolfgang Zimmermann; Robert Kammerer
• Keywords: Placentation

Abstract Background Pregnancy-specific glycoprotein ( PSG ) genes belong to the carcinoembryonic antigen CEA gene family, within immunoglobulin superfamily. In humans, 10 encode closely related secreted glycoproteins. They are exclusively expressed in fetal syncytiotrophoblast cells and represent most abundant proteins maternal blood. recent years, a role modulation of immune system possibly avoid rejection semiallogeneic fetus facilitate access trophoblast resources via blood has been suggested. Alternatively, they could serve as soluble pathogen decoy receptors like other members family. Despite their clearly different domain organization, similar functional properties have also observed for murine bat PSG. As these species share hemochorial type placentation seemingly convergent formation during evolution, we hypothesized that placentae support evolution families. Results To strengthen this hypothesis, analyzed 57 primate which exhibit or epitheliochorial placentation. nearly all apes some each be retrieved from genomic databases, while 6 24 were found Old World monkey genomes. Surprisingly, only 1 7 identified New monkeys. Interestingly, no more distantly primates with lemurs lorises. The exons encoding putative receptor-binding domains strong selection diversification revealed by rapid loss orthologous relationship high ratios nonsynonymous synonymous mutations. Conclusion distribution trophoblast-specific PSGs pattern supports hypothesis still evolving optimize fetal-maternal interactions mammals intimate contact mother