KI ReproNET activities
KI ReproNET monthly organizes webinars and annual symposia. Additionally, this homepage serves as a platform for sharing information on open positions, relevant events, and news.
Webinar schedule for the spring:
Start time: 12:15 pm (online)
Format: 30 min talk + 10 min QA
Zoom link https://ki-se.zoom.us/j/68809920689?pwd=HgJQvOMc1X7ohnGPiQDl4aFeiTbpMC.1
Meeting ID: 688 0992 0689
Passcode: 021412
Tuesday the 11th of February
“Human embryonic genome activation in real life and in vitro”
Webinar chair and presentation summary: Nina Boskovic
Human Embryonic Genome Activation in real life and in vitro- by Prof. Juha Kere
The seminar discussed the early stages of human embryo development, focusing on the role of the DUX4 gene. DUX4 transcripts appear transiently in zygotes, and fourfold degradation of oocyte-specific mRNAs occurs until the 4-cell stage. Embryonic genome activation (EGA) begins at this stage with the transcription of 32 mRNAs, including several PRDL homeobox family transcription factors.
Recently, Prof. Juha Kere’s group, using whole-genome methods, showed that DUX4 has a major role in chromatin remodeling and enhancer activation, interacting with Mediator proteins. Downregulation of DUX4 in zygotes delays oocyte mRNA degradation but does not affect cell division. Interactions of 23 EGA-related transcription factors (TFs) with clusters of other TFs and chromatin modifier proteins form a network, helping to understand the regulation of EGA. To facilitate EGA research, 8-cell-like human cells were reprogrammed using a DUX4 expression pulse, providing a robust model for further studies.
Friday the 28th of March
”Dissecting the mammalian egg coat structure to unveil the block to polyspermy, understand infertility and developing non-hormonal contraception”
Chair of the webinar: Laia Torres Masdéu.
The human zona pellucida (ZP) is made of proteins ZP1-4, which form heterofilaments that are essential for fertilisation. This talk introduced how ZP2 cleavage prevents polyspermy by altering the structure of the egg coat. Previously, ZP2 cleavage by ovastacin was thought to block sperm, but recent findings by Prof Luca Jovine’s group suggest it actually tightens and hardens the egg coat matrix, ensuring a permanent block to polyspermy. Structural studies conducted by Prof Jovine’s lab have revealed that the ZP filaments, thanks to the great abundance of cleaved ZP2, reorganise after fertilisation, compacting the ZP. Interestingly, mutations in ZP proteins have been related to infertility, and anti-ZP2 monoclonal antibodies have been seen to induce reversible infertility without disrupting the ovaries. These insights offer potential for non-hormonal birth control, as well as a better understanding of human infertility.
Tuesday the 22nd of April
”The Immunological Niche of the Intervillous Space in the Placenta”
Chair of the webinar: Sara Vikberg.
In this talk Docent Helen Kaipe discussed the interplay between the fetal placenta and the maternal immune system during pregnancy. Maternal blood flows through the intervillous space of the placenta from late first trimester to provide gas exchange, nutrients and antibodies to the fetus and to remove waste. The blood flows through the placenta in a shunted manner due to the tree-like structures of fetal placental tissue, leading to longer exposure of maternal circulating immune cells to the placental microenvironment. Helens group has shown that the immune cell composition in the blood that flows through the intervillous space of the placenta, intervillous blood, differs from that of the systemic circulation, with accumulation of certain immune cells. This suggests that the placenta creates a unique immunological niche. The group has also shown that the immune cell composition in the intervillous space is dynamic throughout gestation, adapting to the needs of different times of gestation and the growing fetus.
Thursday the 22nd of May
”Contraceptive use and abortions in Stockholm: trends and disparities”
Tuesday the 10th of June
”Tissue-Specific Immune Dynamics in the Uterus: Insights from Endometrial NK Cells”