A new study in Science Advances, led by international researchers, reveals why childhood memories can last a lifetime. They found that a molecule called KIBRA acts like glue, binding with other molecules to help memories form and stay strong over time. Unlike past research focusing on single molecules, this study shows how these molecules team up to maintain long-term memories.
Understanding how memories are stored will aid in addressing memory-related disorders in the future, notes Todd Sacktor, a SUNY Downstate Health Sciences University professor and study investigator. The discovery of KIBRA’s role as a “glue” molecule aligns with Nobel Laureate Francis Crick’s brain memory storage theory.
Neurons encode memories through strong and weak synapse patterns, which is crucial for neural network function. Despite synapse molecule instability, KIBRA’s interaction with protein kinase Mzeta (PKMzeta) in mice suggests stability in memory formation despite PKMzeta’s short lifespan.
Their experiments reveal that KIBRA plays a crucial role in long-term memories, acting as a persistent glue at strong synapses and binding with PKMzeta. According to Todd Sacktor from SUNY Downstate, KIBRA is strategically placed at active synapses during memory formation.
PKMzeta then attaches to the KIBRA-synaptic tag, strengthening these synapses. This process allows newly formed KIBRA to attract more PKMzeta, reinforcing memory retention. Breaking the KIBRA-PKMzeta bond erases old memories, as their Science Advances study shows. Previous findings have shown that increasing PKMzeta could enhance weak memories, seemingly randomly. However, the specific synaptic tagging by KIBRA explains this enhancement by targeting memory-specific sites.
The persistent synaptic tagging mechanism, explained for the first time, has clinical relevance for memory disorders,” notes Fenton from NYU Langone Medical Center. The study validates Francis Crick’s 1984 concept of memory storage in the brain, likened to Theseus’s Ship from Greek mythology, where new parts replace the old to maintain continuity.
Sacktor adds that KIBRA and PKMzeta act similarly, allowing memories to endure despite protein turnover, a theory Crick speculated on decades ago.
In conclusion, the new study provides a biological explanation for how memories last a lifetime. Researchers identified KIBRA as a critical molecule that acts like glue at synapses, helping to maintain strong connections essential for memory formation. This discovery sheds light on potential avenues for understanding and treating memory-related conditions in the future.
Journal reference:
- PANAYIOTIS TSOKAS, CHANGCHI HSIEH et al., KIBRA anchoring the action of PKMζ maintains the persistence of memory. Science Advances. DOI: 10.1126/sciadv.adl0030.