The research suggests that PKMzeta [a protein that's part of memory creation] works alongside another molecule, called KIBRA (kidney and brain expressed adaptor protein), which attaches to synapses activated during learning, effectively “tagging” them. KIBRA couples with PKMzeta, which then keeps the tagged synapses strengthened.

Intriguiging. I wonder how this is related to short-term/working memory?

It also appears KIBRA dysfunction is closely related to Alzheimers.