Could the ovary produce eggs forever? Implication for decreased ovarian reserve!
Can we stop the process of egg depletion, prevent decreased ovarian reserve, and eliminate premature menopause? Researchers in Germany have found that an enzyme, (Histone 3K4 methyltransferase gene Mll2), can keep small eggs dormant. This protein is abundantly expressed in a critical location in the DNA of immature and inactive eggs. The researchers found that the enzyme is shifted and degraded in the growing eggs! This research is fascinating since they were able to investigate tiny cells like the oocyte.
Eggs are kept dormant for many years in the woman ovary. A certain number of eggs (estimated to be about a 1000 egg) start to grow every month, and they all die except for one that will ovulate to produce a mature egg. Increase depletion rate of the eggs can lead to decreased ovarian reserve, a prevalent cause of infertility in young women. It can also lead to premature menopause.
I ask the question could inactivation of this enzyme be causing decreased ovarian reserve? And could we stop this process to maintain a healthy number of eggs in older women?
1. MLL2 conveys transcription-independent H3K4 trimethylation in oocytes. Courtney W. Hanna, Aaron Taudt, Jiahao Huang, Lenka Gahurova, Andrea Kranz, Simon Andrews, Wendy Dean, A. Francis Stewart, Maria Colomé-Tatché & Gavin Kelsey. Nature Structural & Molecular Biology (2018), doi:10.1038/s41594-017-0013-5