An interactive timer for homologous recombination
“In earlier studies we found that the chromosomes are moved along the nuclear envelope during meiosis to help the homolog sorting process”, says Verena Jantsch. “We also observed that this process stops at some point, but what we didn’t know before was how this movement was timed.” In their study the scientists were able to identify SUN-1 as a key mediator to integrate signals that lead to sustaining the chromosome movement process until essential meiotic tasks required to build a crossover had been fullfilled. The movement of chromosomes and its timing are important for the production of healthy germ cells. Misregulations of this system can often be lethal or have serious repercussions for the offspring.
One step closer to finding the “holy grail” of meiosis
This finding adds another puzzle piece to the “holy grail” of meiosis: how do meiocytes control that each chromosome at least receives one crossover? Earlier the Jantsch group discovered that SUN-1 is the bridge that connects chromosomes to the movement apparatus. Their current finding adds another function to the portfolio of SUN-1. “The more research we do on this topic, the more important SUN-1 becomes for the process of homologous recombination”, explains Alexander Woglar, first author of the study. “Crossovers are vital for faithful chromosome segregation and they are a major source to introduce genetic variation in the offspring for the majority of all life larger than the microscopic.” The results of this study were recently published in PLOS Genetics and present a major advance in this highly competitive field of research.
Woglar A, Daryabeigi A, Adamo A, Habacher C, Machacek T, La Volpe A, Jantsch V. Matefin/SUN-1 Phosphorylation Is Part of a Surveillance Mechanism to Coordinate Chromosome Synapsis and Recombination with Meiotic Progression and Chromosome Movement.
In PLoS Genetics (2013).