Maternal stress "memory" affects grandson's biology

The mother's reaction to stress can even affect her grandchildren

Biologists at the University of Iowa found that under certain conditions, nematode mothers undergoing heat stress not only pass on the legacy of this stress exposure to their offspring, but also pass them on to their offspring.

Researchers led by Wiener Prallard, associate professor of the Department of Biology and the Aging Mind and Brain Initiative, observed how nematode mothers react when they feel danger, such as temperature changes, which are harmful or even fatal to animals

Examples of this genetic cascade are everywhere, even in humans

In this study, biologists wanted to find out how memories of exposure to stress are stored in egg cells

Prallard explained: "Genes have a'memory' of past environmental conditions.

Prallard and her team looked for clues in nematodes, a type of organism that scientists often study

The research team discovered that HSF1 absorbed another protein, an enzyme called histone 3 lysine 9 (H3K9) methyltransferase

However, Prakhard's team observed something completely different

Prallard said: "We found that HSF1 cooperates with the mechanism that normally'resets' gene expression memory during embryonic development, rather than establishing this stress memory

One of these newly silenced genes encodes the insulin receptor, which plays a key role in the metabolic changes of human diabetes.

"We found that it is more noteworthy that if the mother is exposed to stress for a short period of time, only the offspring developed by her germ cells will have this kind of memory in the uterus," Prallard said.

The researchers plan to investigate these changes further

Molecular Cell

Gene bookmarking by the heat-shock transcription factor programs the insulin-like signaling pathway.