An Alternative Mechanism for Long-Term Memory Formation
Long-term memory (LTM) formation has been linked with functional strengthening of existing synapses as well as other processes including de novo synaptogenesis. However, it is unclear whether synaptogenesis can contribute to LTM formation. Using alpha-calcium/calmodulin kinase II autophosphorylation-deficient (T286A) mutants, we demonstrate that when functional strengthening is severely impaired contextual LTM formation is linked with training-induced PSD95 upregulation followed by persistent generation of multiinnervated spines (MIS), a type of synapse that is characterized by several presynaptic terminals contacting the same postsynaptic spine. In the chapter, the molecular processes involved in generation of MIS and properties of MIS-dependent memory will be discussed.
KeywordsαCaMKII autophosphorylation Multiinnervated spines PSD-95 Fear memory Hippocampus
- Giese, KP (2012) Long-term potentiation and memory. In: Memory Mechanisms in Health and Disease, KP Giese, ed., World Scientific, Singapore 1–17Google Scholar
- Popov VI, Deev AA, Klimenko OA, Kraev IV, Kuźminykh SB, Medvedev NI, Patrushev IV, Popov RV, Rogachevskii VV, Khutsiyan SS, Stewart MG, Fesenko EE (2005) Three-dimensional reconstruction of synapses and dendritic spines in the rat and ground squirrel hippocampus: new structural-functional paradigms for synaptic function. Neurosci Behav Physiol 35:333–341CrossRefPubMedGoogle Scholar
- Radwanska K, Medvedev NI, Pereira GS, Engmann O, Thiede N, Moraes MF, Villers A, Irvine EE, Maunganidze NS, Pyza EM, Ris L, Szymanska M, Lipinski M, Kaczmarek L, Stewart MG, Giese KP (2011) Mechanism for long-term memory formation when synaptic strengthening is impaired. Proc Natl Acad Sci U S A 108:18471–18475CrossRefPubMedCentralPubMedGoogle Scholar