The team of AMU researchers led by Associate Professor Piotr Ziółkowski from Laboratory of Genome Biology, Institute of Molecular Biology and Biotechnology has published a paper in the prestigious Proceedings of the National Academy of Sciences of the United States of America. PNAS is a journal of the U.S. National Academy of Sciences that specializes in publishing original research of high significance in the biological, physical and social sciences.
Crossing-over, is the process of exchanging chromosome fragments from both parents that occurs during gamete formation. It is the primary mechanism for ensuring genetic variation in all organisms reproducing sexually. The control of crossing-over is not fully understood, although it may be of great importance in plant and animal breeding. The work of scientists from Adam Mickiewicz University allows us to identify a new pathway of crossing-over regulation in plants.
– We investigated variability in crossing-over frequency in a model plant, Arabidopsis thaliana, and thus identified the SNI1 gene as one of the major factors modifying crossing-over in natural populations of Arabidopsis,’ says AMU professor Piotr Ziółkowski – SNI1 is an element of the SMC5/6 complex, which is closely related to cohesin and condensin, protein complexes that enable proper condensation of chromosomes and their segregation during cell division. Until now, the role of SNI1 and SMC5/6 in meiosis was completely unknown.
Professor Piotr Ziółkowski’s Team of Researchers at AMU
The SNI1 variants identified by the AMU scientists differ, among other things, in their response to elevated temperature. Mutant sni1 and other mutants of the SMC5/6 complex show similar effects on the interference-independent crossing-over pathway, leading to an increase in the number of events and their shift towards the ends of chromosomes.
Therefore, the findings of the AMU researchers show that the SMC5/6 complex, which is known for its role in DNA damage repair, is also important for crossing-over control.