Lab News

Paper published in Cell - a conserved fertilization complex bridges sperm and egg

17 Oct 2024

The life of each one of us began when a sperm and an egg came together. But what actually happens at a molecular level? In our latest work published in Cell, jointly led by our fantastic postdoc Victoria and equally fantastic PhD student Andreas, we discovered a conserved fertilization complex that bridges sperm and egg in vertebrates. Most surprisingly, while the trimeric ‘key’ on sperm is conserved across vertebrates, it recognizes distinct ‘locks’ on the egg in mammals and fish. This presents an intriguing model of a conserved complex bridging sperm and egg through divergent egg factors in vertebrates.

This study was a real tour-de-force, employing AlphaFold-based structural predictions, in vivo genetic experiments in zebrafish and mice, and biochemical and proteomic analyses. This was only made possible based on the wonderful collaborative environment in the Pauli lab and across our Vienna BioCenter campus, as well as key contributions from our international collaborators, particularly by Yonggang Lu and Masahito Ikawa in Japan (mouse experiments) and Jeffrey Lee’s lab in Canada (in vitro protein biochemistry). A big thank you to everyone who contributed!

To read more about our story, please check out several media channels that have covered our work:

• New York Times
• Science
• Nature
• IMP News
• in German: Der Standard
• and here an explanatory video produced by Philipp Dexheimer together with our IMP communications team

Credit for the time-lapse movie of zebrafish fertilization: Victoria Deneke, Pauli lab, IMP

New pre-print by the Pauli and Calo labs on maternal-zygotic ribosomes

30 Aug 2024

New pre-print alert!

In this collaborative study jointly led by Arish Shah from Eliezer Calo’s lab (MIT) and Frieda Leesch from the Pauli lab, we investigated the previously described maternal-zygotic ribosomal system in zebrafish. We discovered that maternal and somatic subunits are compatible with each other and can form hybrid ribosomes. In addition, we found that maternal-type ribosomes are not only made during oogenesis but are generated in primordial germ cells likely throughout the life of the fish. Thus, the previously described dual ribosomal system extends to the germline of the fish, opening the possibility that it may control germline-specific translation.

Big congrats to all authors!

Summary scheme credit to Frieda (Friederike Leesch, PhD thesis 2023)

Goodbye to our VBC summer student Julen

30 Aug 2024

The summer is coming to an end and unfortunately we had to say goodbye to our VBC summer student Julen Casulleras Alava. Over the past two months, Julen worked with Ida on investigating diapause in different fish species. Ida and Julen formed a fantastic team, diving into this new research direction and performing together the very first experiments exploring translational regulation in our newest model organism, the African turquois killifish!

While we will really miss Julen’s excitement, curiosity and passion for science, we are 100% sure that he will do extremely well whereever his next steps will lead him. Julen, let’s stay in touch, and all the best for your (bright) future!

For more information on the Vienna BioCenter Summer School, check out this website.