Because there is no automatic chemical affinity between these two molecules in the process but is carried out by a RNA based molecular machine, the precise construction of which is encoded in DNA, this whole process is code driven, not chemistry driven.
The article points out that it is these transfer RNA’s that actually carry out the translation of RNA molecules into the appropriate amino acid chain by a pre-ordained set of protocols encoded into the DNA molecule. So this is precisely the process that defines a semiotic system.
While it has to be pointed out that the author of this article in no way draws the same conclusion about the origin of life that my own article does, it makes some very similar points along the way, for example:-
“The idea that the cell is a semiotic system, in short, raises fundamental questions about the nature of life and invites us to take a new look at the problem of its origin”.
Also
“Signs, meanings and conventions, however, do not come into existence of their own. There is always an “agent” that produces them, and that agent can be referred to as a codemaker because it is always an act of coding that gives origin to semiosis”.
The article points out that semiosis in a eukaryotic cell goes far deeper than just the coding used to translate genes into proteins. In fact the article goes on to list an additional 11 separate semiotic codes the cell uses to function.
(1) The transcription codes
(2) The gene splicing code
(3) The translation pausing code
(4) The DNA structure code
(5) The chromatin code
(6) The translation framing code
(7) The modulation code
(8) The genome segmentation code
(9) The adhesive Code
(10) The sugar Code
(11) The histone Code
The article goes on to suggest they may well prove to be many more additional codes built into the cell.
Without question, as an information processing system the eukaryotic cell is a semiotic system without equal !