This paper hypothesizes that postsynaptic CaMKII (calcium/calmodulin-dependent protein kinase II) receives synaptic input and then interacts with via phosphorylation, suggesting that memories may be encoded in the microtubules in this way. They note that the size and shape of CaMKII appears to be just right to phosphorylate the hexagonal lattices of tubulin proteins in microtubules. The paper also can “demonstrate microtubule-associated protein logic gates, and show how patterns of phosphorylated tubulins in microtubules can control neuronal functions by triggering axonal firings, regulating synapses, and traversing scale.”. Via ScienceDaily.
Travis J. A. Craddock, Jack A. Tuszynski, Stuart Hameroff. Cytoskeletal Signaling: Is Memory Encoded in Microtubule Lattices by CaMKII Phosphorylation? PLoS Computational Biology, 2012; 8 (3): e1002421 DOI: 10.1371/journal.pcbi.1002421.