To open things up a bit ask yourself, what does DNA do? Is it possible to enlarge our understanding of "computation" by thinking deeply about this? .d.
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I didn't know who David Baltimore was so I looked him up on wiki. Oh, that David Baltimore... Fascinating character, real power house of molecular genetics. I only studied a very little of that in one particular area, but mostly I was exposed to it through lab meetings and tried to follow the discussions. Back then (about ten years ago) The Cell, by Alberts et al was the textbook of the field (molecular biology of the cell), in which I only read and studied sections. It was the best textbook I ever read. It was assembled from recent articles some of which were comissioned as re-writes of published work--summaries so to speak. Each chapter had an extended intro for an overview.
Maybe it was the illustrations, maybe it was my experience as a mechanic, but my operating metophor was little molecular machines working in a machine city, with the nucleus as the palace or the vast complex downtown, City Hall, overlords of the city.
I never conceived of the activities I was reading about as compututions, but mechanical actions of opening this port or that to let this or that molecule in or out of the city, transporting this molecule from here to there, building this structure or that, building this molecule or that and hooking it to a transport system to be taken somewhere else. The eternal vigilance of police molecules arriving on scene to get things under control.
What does DNA do? DNA runs the city. It runs the city through its bureaucrats RNA and various lesser nomes the enzymes---and weirdest of all, it runs itself the same way. The DNA complexes are both the masters and the master plan all rolled into one.
Anyway, computation? I don't what this means. I am not being skeptical exactly, or doubtful. I just need more detail about how computation fits into the picture. But here is one thing I asked myself, where is the clock? All these activities are timed in some fashion, so where is the clock? Or what is the clock? This bares on the idea of computation if you conceive computation as some form of counting. Do cells count?
CG