“Cellular Memory” of DNA Damage in Oocyte Quality Control
Females are born with a finite number of eggs that are steadily depleted throughout their lifetime. This reserve of eggs is selected from a much larger pool of millions of precursor cells, or oocytes, that form during fetal life. So there is a substantial amount of quality control during the process of forming an egg cell, or ovum, that weeds out all but the highest quality cells. New research from Neil Hunter’s laboratory at UC Davis reveals the surprising way that this critical oocyte quality control process works.
Previous research in the Hunter lab showed that a gene called Rnf212 is required for chromosomes to undergo crossing over during the early stages of oocyte development. The researchers were surprised to find a new, late function for Rnf212 in the oocyte selection process. The results are published Sept. 27 in the journal Molecular Cell.
During oocyte quality control, a decision is made whether each oocyte should continue and join the reserve of eggs, or undergo apoptosis — cellular death.