Embryonal non-coding RNAs in the human placenta and the maternal circulation.

• Applicants: Professor Dr. Udo Markert; Professorin Dr. Manja Marz
• Subject Area: Gynaecology and Obstetrics
• Term: from 2016 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 315156279

Non-coding RNAs (ncRNAs) play a central and regulatory role in almost all cells, organs, and species which has been broadly recognized since the human ENCODE project and several other genome projects. Nevertheless, we know only a small fraction of ncRNAs. Moreover, long non-coding RNAs are known only for about five years and have been very marginally investigated in the placenta. To date, most examples of ncRNAs which have been identified to be specific for fetal tissues, such as placenta, are members of the group of microRNAs (miRNAs). It can be expected that the fairly larger group of other ncRNA exerts much more powerful influences and effects. Thus, we see the need to expand the knowledge about ncRNAs in the placenta and ncRNAs released from it.Inside the placenta, the fetal syncytiotrophoblast forms the interface between fetus and mother, from which exosomes and microvesicles are permanently released into the maternal circulation. These particles contain fetal proteins and RNA for communication with neighboring and distant maternal cells. The number, size and content of particles may reflect or predict placental disorders and can be assessed in maternal serum samples. As many of the known trophoblast-specific miRNAs are human-primate-specific it may be expected that also other, currently unknown ncRNAs are species-restricted and can, therefore, only be investigated in human placentae. Several severe pregnancy pathologies, including preeclampsia, are human-specific and their pathomechanisms are not yet understood. We expect that the knowledge on novel placental ncRNA will have the potential of revolutionizing the understanding of regulation processes inside the placenta and of fetal-maternal communication.In this proposed project, we aim to answer the following questions:(1) Which (partially newly characterized) ncRNAs are fetus specific?(2) Which of these fetally expressed ncRNAs are derived from trophoblast cells? Which trophoblast-derived ncRNAs reach maternal blood packed within (3) microvesicles or (4) exosomes? Furthermore, we aim to identify highly abundant ncRNAs via PCR from maternal serum. This may contribute to identification of disease associated marker genes in subsequent projects. Finally, we plan to determine differences between natural trophoblast ncRNAs and ncRNAs in commonly used cell lines (JEG-3 choriocarcinoma cells and HTR8/SVneo immortalized first trimester trophoblast cells). Subsequently, both cell lines will be used for silencing and overexpression of trophoblast specific ncRNA for identification of their targets and basic functions.

• DFG Programme: Research Grants