A Biosemiotic Approach To Epigenetics: Constructivist Aspects

Abstract

Recent findings in molecular cell biology of mammalian reproduction demonstrate the importance of epigenetic mechanisms taking place during the oocyte-to-embryo transition. Employing a semiotic framework this epigenetic ‘reprogramming’ can be shown to be a subject’s active achievement that enables the construction and activation of a diploid embryonic genome. Fertilization therefore is not merely the physical union of sperm and ovum as the paternal contribution is not just received passively, but has to be constructed actively by the perceiving organism: its entire structure has to be “put in form”. Thus the oocyte-to-embryo transition can be regarded to be a natural semiotic process. When applying a general model of semiosis, the biological process of mammalian reproduction displays a structural analogy with the course of perception: the oocyte – a single-celled mammalian organism capable of creating Umwelt– extracts information from its environment. As soon as the pronucleus of the spermatozoon is incorporated into the oocyte, active and specific transformations are performed on the paternal genome. By exchanging certain proteins the chromatin structure is altered and a significant and selective demethylation of the paternal genome takes place elucidating the creative role of the zygote organism as an interpreter. All these epigenetic modifications are realized by maternal means and do alter the content of information given by the paternal genome. Therefore, the activation of the embryonic genome seems to reveal basic patterns of constructivist epistemology. As obviously the found principles are not an exclusive feature of perception performed by so-called higher organisms, but a general characteristic of cellular life, ’construction of information’ seems to be a basic quality of life itself. Moreover, the proposed interpretation could be a valid argument for evolutionary epistemology since basic mechanisms of perception can even be found in a single-celled organism, as this subject is able to arrange and interpret its genome. Conclusively, it can be postulated that development of cognition starts and started within a single cell – ontogenetically as well as phylogenetically. Another benefit of our semiotic analysismaybe the opportunity of overcoming genetic reductionism