A key regulator of male fertility

The molecular mechanism triggering the process of spermatogenesis has been discovered

Anna Kerman, XX2 century, based on Medical Xpress: Scientists identify key regulator of male fertility

Researchers from the Cincinnati Children's Hospital Medical Center (Cincinnati Children's Hospital Medical Center) reported that they were able to detect a molecular and genetic "switch" that activates the production of male sperm at a certain age. The results of the study are published in the publication Genes and Development (Maezawa et al., Polycomb directs timely activation of germline genes in spermatogenesis).

The mechanism is regulated by a protein complex called Polycomb Repressive Complex 1, PRC1. The researchers were surprised when they found that PRC1 activates specific germ genes and controls the synthesis of healthy sperm. When male mammals are born, they already have reproductive germ cells necessary for the production of sperm. And the protein complex in question "turns off" specific genes and "freezes" sperm production until the individual reaches the age of puberty.

In a new study, scientists have demonstrated that upon reaching puberty, the PRC1 complex changes. At this point, it blocks the components of the germinal genes, which, in turn, themselves block the synthesis of sperm. This is how the process of spermatogenesis, the production of mature sperm, is started.

"For a long time, scientists have been wondering how genes related to reproduction are activated at a well-defined moment. Our study provides an answer to this fundamental question, because we were able to discover a new epigenetic mechanism that controls the activation of the process of spermatogenesis, – says Satoshi Namekawa, a leading researcher and an employee of the Department of Reproductive Sciences (Division of Reproductive Sciences) at the Perinatal Institute Cincinnati Children's Hospital. – This is very important, since the inhibitor of sperm production PRC1 is known for its other function. But at the right moment, it provides activation of the genes responsible for sperm synthesis."

In the course of the work, it was also demonstrated that in the absence of the PRC1 complex, smaller testicles are formed in experimental animals, and the individuals themselves are sterile – they do not produce normal sperm suitable for fertilization. But the question "how exactly PRC1 turns from an inhibitor into an activator", scientists have yet to find an answer. In addition, the new study raised other questions for the scientific community. How can lifestyle, through epigenetics, affect men's ability to conceive? How do environmental factors influence the "on" or "off" of genes in our body? It is also important that the protein complex PRC1 and its accompanying compounds can now be considered as potential markers of male infertility – which means, theoretically, the results of the new work can be applied in clinical practice.

Portal "Eternal youth" http://vechnayamolodost.ru  21.09.2017