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The protein complex known as Polycomb Repressive Complex 1 PRC1. PRC1 activates specific germline genes and the production of healthy sperm. It is responsible for production of health male sperm.
Male mammals are born with all the reproductive germline cells and inheritable genetics needed to make healthy fertile sperm and offspring. But the sperm isn’t fertile at childhood.
PRC1 also blocks the specific genes and the activation of fertile sperm production until reproductive age.
Researchers show in their current study that when mice reach reproductive age, the PRC1 protein complex changes. It sheds reproductive germline gene components that block fertile sperm production and substitutes in a component that start spermatogenesis.
The repressor of sperm production, PRC1 also promotes gene activation to produce sperm at maturity. The scientists also found that when PRC1 is disrupted, such as in male mice bred to not express PRC1, the animals have smaller testes and are unable to produce healthy sperm or offspring.
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