A "Nanobrain" For Unicellular Organisms Via A System Of Interconnected Signal-Transducing Proteins

I mentioned earlier that some studies are starting to show evidence of cognition in unicellular organisms, including slime molds and bacteria, that lack brains or nervous systems. However, there perhaps exists an alternative plausible mechanism explaining how these attributes could exist in these brainless creatures.

This is the fact that, in every unicellular organism, the transmission of signals between components within the cell occurs regularly. There is a network of proteins that constitute the medium through which these signals are conveyed, with each protein assuming the same role as a neuron in an organism with a nervous system, and the ends of proteins, referred to as structural domains, assuming the same role as the ends of neurons, with both the structural domains of proteins and the ends of neurons transmitting and receiving signals to and from other proteins and neurons, respectively.

We know that the phenomenon of convergent evolution, in which different biological approaches to the same function arise in disparate taxa, is a common aspect of the evolutionary landscape. I find it plausible that a system of proteins through which signal transuction occurs, forming the equivalent of a "nanobrain" which is analagous to the brains of multicellular organisms, has allowed unicellular microorganisms to evolve the same functions of cognition, communication, and possibly consciousness, sentience, and self-awareness, as well as multicellular neuronal organisms.

References:
Marks, Friedrichs; Klingmüller, Ursula; Müller-Decker, Karen. Cellular Signal Processing: An Introduction to the Molecular Mechanisms of Signal Transduction. Garland Science, Taylor and Francis Group, LLC. Print. (https://books.google.com/books?id=0TIWBAAAQBAJ&printsec=frontcover&dq=cell+signal+transduction&hl=en&sa=X&ved=0ahUKEwi1sJbzgr7SAhVJz2MKHVu-BLMQ6AEIMjAF#v=onepage&q&f=false)