New research published in Cell Reports suggests a memory suppressor gene has strong links to a number of neuropsychiatric disorders, including autism.

MicroRNAs are short molecules found in cells that regulate gene expression by functioning as a "dimmer switch" for one or more genes; they control a wide variety of cellular processes, including learning and memory. Although microRNAs can be found in virtually every cell and contribute to the "fine-tuning of gene expression," their functional roles in learning and memory have been largely unexplored. However, researchers have newly learned that one specific microRNA, called miR-980, functions as a memory suppressor in multiple brain regions.

For the study, researchers examined the effect the miR-980 had on olfactory memory in fruit flies. To identify which microRNAs participated in memory formation, they inhibited 134 different microRNAs and examined their effect on memory. They discovered an inverse relationship between the microRNA and memory: miR-980 inhibition enhanced memory in the fly model, while its overexpression impaired it.

"We wanted to know what happens to behavior when we change the levels of these microRNAs," researcher Ron Davis said in a statement. "When we reduced the level of miR-980, the flies had better memory — that’s something new and surprising."

However, they were mostly interested to see which genes miR-980 regulated. They found miR-980 targets and inhibits a gene known as A2bp1, which suggests suppressing this specific microRNA could inadvertently improve memory and increase the gene expression of A2bp1. However, A2bp1 has also been associated with an increased risk of developing autism and epilepsy, meaning overexpression could also up one’s risk for developing autism.

"It is intriguing that our studies show that adult stage-specific increases in A2bp1 abundance improve aversive olfactory memory, independent of any developmental function for the protein, and human [autisum] is a spectrum brain disorder that is associated with poor to extraordinarily robust learning and memory capacities," researchers wrote in the study.

Although they experimented on the olfactory memory of fruit flies, researchers say their results have important implications on humans.

"[T]he fact that A2bp1 plays an influential role in autism and epilepsy in people brings a real human connection to the study," Davis added. "It's very exciting."

Researchers say the link between the microRNA miR-980 and a disease-linked gene may help uncover even more nervous system dysfunctions.

Source: Guvan-Ozkan T, Busto G, Schutte S, Cervantes-Sandoval I, O’Dowd D, Davis R. MiR-980 Is a Memory Suppressor MicroRNA that Regulates the Autism-Susceptibility Gene A2bp1. Cell Reports. 2016.