A team of scientists led by the head of the research group at the Department of Biology, Nicola Silva, has made a significant achievement in research into the reduced or impaired function of the Synaptonemal complex, which may be one of the causes of sterility. The paper by an international team of authors was published in the prestigious scientific journal Nature Communications in March 2025.
A team of scientists led by Nicola Silva from the Institute of Biology of the Faculty of Medicine, Masaryk University recently discovered new mechanisms that promote the correct chromosome segregation during oocyte development in the nematode Caenorhabditis elegans. Dr Silva's research group is studying various aspects of meiotic chromosome segregation, including how cells repair DNA to allow proper genetic linkage and how chromosomes are held together by a special structure called the synaptonemal complex (SC).
Gametes (eggs and sperm) need to have only half the genetic information to produce a zygote with a complete set of chromosomes after fertilisation. In order for the chromosomes to be properly partitioned, each homologous chromosome must recognize its companion and link up, allowing genetic exchange and proper reshuffling of DNA. This complex process involves the formation of controlled breaks along the DNA that serve as triggers for recombination.
Using an advanced genome editing method called CRISPR, the scientists created special cell models that allowed them to discover a new protein called BRA-2. This has emerged as a key player in the proper linking of chromosomes. Together with another protein, HIM-17, it helps ensuring that the synaptonemal complex is formed only between the correct chromosomes. When BRA-2 is missing, the system breaks down - the chromosomes can recognize each other but they can't connect properly, which leads to infertility. If together with BRA-2, HIM-17 is absent as well, then chromosome also lose their ability to pair and synapsis is abrogated altogether.
This discovery is an important step towards understanding the mechanisms that control the formation of sex cells. In humans, disruptions in these processes have been linked to infertility, but the exact regulatory pathways are not yet well understood. New findings are thus helping to untangle the complex web of inheritance and cellular processes.
The research was carried out thanks to the financial support of a standard grant from the Czech Science Foundation (GAČR). It is also the result of an international collaboration of our research group with Professor Verena Jantsch from Max Perutz Labs at the University of Vienna, Professor Sarit Smolikove from the University of Iowa, Professor Judith Yanowitz from the University of Pittsburgh and Professor Monique Zetka from McGill University in Montreal. The results of the research were published in the highly prestigious journal Nature Communications.
In recent months, the Faculty of Medicine has been working on a gender audit to analyse the Faculty's approach to individual processes in terms of ensuring equality of opportunity and planning support activities in this area. The audit also serves as a basis for the development of the Masaryk University Gender Equality Plan 2025-2028.
At the breakfast event hosted by Tomáš Kašpárek on Monday, October 7, the special guests were Jaroslav Štěrba and Regina Demlová, two key figures from the CREATIC Centre of Excellence at the Faculty of Medicine, Masaryk University.
