Epigenetic Code That Enables "LIFE"

According to S.B. Baylin and K.E. Schuebel. 2007. Nature 448:548-549, "The intriguing--and daunting--challenge now is to understand the process of how and when specific DNA regions are controlled to produce the cellular diversity that underpins the development and maintenance of a single organism".

They state further that "Epigenetic changes lie at the heart of how organisms generate different----cellular responses----to environmental factors and stress".

They elaborate that an epigenetic change is an alteration in the heritable states of DNA function produced by altering the chromatin software. Chromatin is composed of histone proteins in combination with DNA. They conclude that chromatin provides the software packaging for the readout of the DNA hard drive.

They say "The central unit of chromatin is the nucleosome, which is constructed from short regions of DNA wound around an octet of histone proteins". This unit can modulate the readout from DNA. Nucleosomes can be physically rearranged on DNA by complexes known as chromatin-remodelling proteins. Such rearranging changes the distance between nucleosomes, and thus the "openness" of the chromatin. Increased openness of the chromatin favors the likelihood that such regions of DNA will be transcribed into RNA. Conversely, epigenetic changes can also lead to histone-dependent compacting of nucleosomes into higher-order aggregrations to form "closed" chromatin, or heterochromatin, thereby preventing, at least changing, transcription.

Histone proteins thus clearly play a determinant role in altering the transcription of given DNA based on particular intra- and inter-cellular epigenetic (i.e., environmental) messaging (e.g., stimuli, factors, stresses). Among other traits, histones are, at least, largely -SH / -S-S- interchange proteins; thus, they are uniquely equipped to change qualitatively and quantitatively their shape (i. e., conformation, "openness" ) and motion in response to "incoming" epigenetic communications.

Such communication requires a "code"; and a code requires a messenger, and means for using that messenger. Based on our real "Systems Biology" research on the electrochemistry of life during five decades, always including the whole live higher organism, we have found since the 1960's that sulfur is the messenger; and thiol (-SH), its derivatives, and its redox couple (i .e., disulfide, -S-S-) are the means for using that messenger.

We have published our findings and interpretations regarding this Epigenetic Code in "Science", "Nature", "Experientia", and dozens of other internationally prominent peer-reviewed scientific journals beginning in the 1960's, and continuing in 2007. We have named the code "The Thiol / Disulfide Environmental Energy Exchange Code", or "TDtriple E Code" for convenience.

The TDtriple E Code supercedes DNA and RNA codes in importance because the latter two are only descriptive biology, and "Life" as we all recognize it only comes via the necessary comunications between the environment(s) and the genome(s) which the TDtriple E Code enables in all organisms.