Preimplantation Embryos Amplify Stress-Induced Changes in Sperm-Derived miRNA Content to Mediate Transgenerational Epigenetic Inheritance.

Chronically stressing male mice can alter the behavior of their offspring across generations. This effect is thought to be mediated by stress-induced changes in the content of specific sperm miRNAs that modify embryo development after their delivery to oocytes at fertilization. A major problem with this hypothesis is that the levels of mouse sperm miRNAs are much lower than those present in preimplantation embryos. This makes it unclear how embryos could be significantly impacted without an amplification system to magnify changes in sperm miRNA content, like those present in lower organisms where transgenerational epigenetic inheritance is well established. Here, we describe such a system for Chronic Social Instability