Evolving tales of autophagy in early reproductive events.

Cells learn to thrive under unfavorable conditions by various mechanisms, and autophagy, self-eating, is one such mechanism. Autophagy is always ongoing in cells at a basal level to turn over old proteins, provide building blocks for new proteins, and to dispose of unnecessary byproducts of metabolism, and normally it does not cause deleterious effects on other parts of basic cellular processes. Autophagy is often dubbed a "double-edged sword", as it is a necessary process for many cells, but its exaggeration may lead to cell death. Evidence is accumulating that autophagy is crucially involved in specific aspects of reproduction. Several recent studies have illustrated how the uniqueness of self-eating is manifested in germ cells and embryos. In this review, we attempt to portray where this relatively young field of autophagy research is heading in the context of reproductive biology research.