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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

Meeting ID: 688 0992 0689

Passcode: 021412

 

Tuesday the 11th of February

Professor Juha Kere

鈥淗uman embryonic genome activation in real life and in vitro鈥

 

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鈥檚 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

Professor Luca Jovine

鈥滵issecting the mammalian egg coat structure to unveil the block to polyspermy, understand infertility and developing non-hormonal contraception鈥

 

Chair of the webinar: Laia Torres Masd茅u.

 

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鈥檚 group suggest it actually tightens and hardens the egg coat matrix, ensuring a permanent block to polyspermy. Structural studies conducted by Prof Jovine鈥檚 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

Docent Helen Kaipe

鈥漈he Immunological Niche of the Intervillous Space in the Placenta鈥

 

Thursday the 22nd of May

Docent Kyriaki Kosidou

鈥滳ontraceptive use and abortions in Stockholm: trends and disparities鈥

 

Tuesday the 17th of June

Professor Niklas Bj枚rkstr枚m

鈥漈issue-Specific Immune Dynamics in the Uterus: Insights from Endometrial NK Cells鈥

Content reviewer:
Daniel Holl
03-04-2025