Everything that happened in your past is not good to remember because it might bring up some of the unwanted memories that you want to leave behind. Researchers are now close to one step in finding out how the engram cells function in a molecular system to make memories.
The engram cell converts the details of memory into a coded form and later activate them when they are remembered again. A recent MIT study reveals that the function is handled by the remodeling of chromatin in engram cells.
The full study is available in nature neuroscience.
The remodeling which grants permission to genes for storing memories happens in various stages and it occurs in several days. Histones can manage how much active specific genes are within a cell.
“This paper is the first to really reveal this very mysterious process of how different waves of genes become activated, and what is the epigenetic mechanism underlying these different waves of gene expression,” says Li-Huei Tsai.
The latest studies have shown that engram cells form networks having particular memories that are found in various parts of the brain. When a particular memory is recalled the network gets activated.
Researchers knew about the first stage of memory formation, where the early genes were converted into engram cells but later they soon return to normal activation level. The main thing that was to be observed as to what happens to the process of the long term storage of the memories.
The fix-up permitted genes on memory storage to be more active. The process does not take place shortly. It performs continuous steps for some days. The study explained that the genes state of performance in a cell can be controlled by Chromatin’s density adjustments.
“The formation and preservation of memory is a very delicate and coordinated event that spreads over hours and days, and might be even months — we don’t know for sure,” Marco says. “During this process, there are a few waves of gene expression and protein synthesis that make the connections between the neurons stronger and faster.”
He also added – “The study is the first to show that memory formation is driven by epigenomically priming enhancers to stimulate gene expression when a memory is recalled.”
The period of the epigenomic modifications were not analyzed by the researchers but Marco thinks they may remain for weeks or even months. Now he aims to find out how Alzheimer’s disease affects the chromatin of engram cells.
Source – mit