There is nobody in quantum optics that is invoking quantum gravity to understand the problems of decoherence in cavity QED, chaos and measurement. Maybe they should. A microtubule is composed of alpha and beta tubulin that can carry phonons and exhibit polarizations. As such the MAPs act to pump energy into the MTs. But MTs also have intrinsic energy from GTP hydrolysis.
MAPs can also behave as environment and cause decoherence, thus acting as orchestrating nodes.
Now let us assert the hypothesis that this energy that is pumped into the MT drives the polarization of the tubulin molecules. These polarizations can be expanded into cylindrical Bessel functions with a mode expansion. For a few number of photons the interactions between the photons are nonlinear. In Coherent Excitations in Biological Systems. Edited by H Frohlich and F Kremer.