Stable presence of proteins is a prerequisite for long-term memory and learning ability.

The two neurons in the brain connect to the area where chemical signals communicate with electrical signals, which researchers believe are key to the brain's ability to learn and to form memories.
However, because proteins at synapses regenerate rapidly, scientists have difficulty explaining how synapses form long-term steady states that promote lifelong learning and memory formation.
now, neuroscientists from Johns Hopkins University have successfully found 164 proteins in synapses in the brains of mice that can stabilize in synapses for weeks to months.
they believe these stable proteins are prerequisites for long-term memory and learning ability.
results published in the latest issue of the journal PNAS. "We already know that synapses stabilize the structure of the rat brain and be able to exist in rats for at least a year," said study author Dr. Richard Huganir, a professor of neurology at Johns Hopkins University School of Medicine.

authors and others have previously known that there is a stable type of protein "crystallin" in the eye lens, and a class of collagen in connective tissue.
, proteins and histones around the nucleus are in a more stable state. "So we think there should be long-term and stable proteins in synapses, and our results suggest that we have found most of them,"
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in the study, the authors and others fed mice food with specific tracking molecules, allowing them to detect proteins in the synapses of the brains of mice.
the trace-active molecule is an amino acid, but because it carries more neutrons, it is more "heavy" than normal amino acid molecules.
can therefore be easily detected during mass spectrometry analysis.
after receiving about seven weeks of food with "heavy" amino acids, proteins with longer half-lifes contained a lower proportion of the "heavy" amino acids than those with shorter half-life. After
, the mice were fed another seven weeks of normal food, and were more likely to retain heavy amino acid components because of the slower rate of protein renewal with longer half-life.
scientists analyzed brain tissue in mice at different stages, and mass spectrometry showed that although most proteins have shorter protein cycles, there are still 164 proteins with longer cycles that can be stable for weeks to months, and that some proteins have an estimated cycle of more than a few years.
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