Cationic peptides cause memory loss through endophilin-mediated endocytosis

Authors:

Eric G. Stokes, Jose J. Vasquez, Ghalia Azouz, Megan Nguyen, Alexa Tierno, Yinyin Zhuang, Vivienne Mae Galinato, May Hui, Michael Toledano, Isabella Tyler, Xiaoyu Shi, Robert F. Hunt, Jason Aoto, Kevin T. Beier

Keywords:

Forgetting; Long-term memory; Long-term potentiation; Molecular neuroscience; ZIP; zeta inhibitory peptide; memory; long-term potentiation; LTP; AMPA; cationic peptides

Abstract:

The zeta inhibitory peptide (ZIP) interferes with memory maintenance and long-term potentiation (LTP) when administered to mice. However, mice lacking its putative target, protein kinase PKMζ, exhibit normal learning and memory as well as LTP, making the mechanism of ZIP unclear. Here we show that ZIP disrupts LTP by removing surface AMPA receptors through its cationic charge alone. This effect requires endophilin-A2-mediated endocytosis and is fully blocked by drugs suppressing macropinocytosis. ZIP and other cationic peptides remove newly inserted AMPA receptor nanoclusters at potentiated synapses, providing a mechanism by which these peptides erase memories without altering basal synaptic function. When delivered in vivo, cationic peptides can modulate memories on local and brain-wide scales, and these mechanisms can be leveraged to prevent memory loss in a model of traumatic brain injury. Our findings uncover a previously unknown synaptic mechanism by which memories are maintained or lost.

< Back to publications

Full article >