Shape-Shifting Proteins Assist in Long-Term Memory
By Jeffrey Ho '20Prions are proteins that can “shape shift” and conglomerate under certain conditions. While there are a variety of harmful prions, such as the one that causes mad cow disease, there are certain prions that help the human body perform normally. One such protein is called Orb2 in flies. The protein CPEM, in humans, is found to be very structurally similar to Orb2, but until recently the function of both proteins have not been thoroughly researched.Scientists from the Stowers Institute for Medical Research in Kansas City, Missouri, recently discovered that aggregates of Orb2 stores long-term memory in fruit flies. The scientists targeted and knocked out the gene for Orb2, inactivating it. This was done in a sample of male fruit flies. These males would try to woo potential female fruit flies, but would not remember being rejected; therefore, they would relentlessly try (unsuccessfully) to pursue the same mate. A similar test was used with odor and its association with food.A second protein, called JJJ2, was found to be responsible for changing the shape of Orb2. When the expression of JJJ2 was increased, Orb2 aggregated in greater concentrations throughout the fruit fly’s brains. Usually, flies require about six hours to learn that an unreceptive female does not want to mate. With increased expression of JJJ2, this was brought down to two hours, and lasted for days.An important distinction to make is that with the over-expression of JJJ2, the memories would have been formed anyways, the memories were just better and sharper. The flies were not increasing their intelligence, remembering new and more things, etc. Kausik Si, a neurobiologist on the team at Stowers Institute, explained that JJJ2 over-expression “lowered the threshold for memory formation” but did not create an environment to create new memories.Due to the specific nature of JJJ2 and Orb2, the scientists predict that control over these molecules can help patients with Alzheimer's recover or retain their memory for a longer period of time. Sources:Sanders, Laura. "Shape-shifting Molecule Aids Memory in Fruit Flies." Science News. Science News, 03 Nov. 2016. Web. 06 Nov. 2016. "What Are Prions?" What Are Prions? N.p., n.d. Web. 06 Nov. 2016.